When people talk about Japanese knives, the region where a knife was made often becomes part of the conversation. Sakai, Echizen, Sanjo and Tosa all have long histories of blade making, and each region has developed its own identity.
But how much does the region really matter when choosing a knife?
I sell Tosa Knives, so naturally I have a strong connection with Tosa and its knife-making culture. But if I’m being truthful, for most of my more than 25 years working as a chef, I didn’t think very much about where my knives were made.
I chose knives because I needed them for a job.
And even today, after becoming a knife seller, I sometimes see a knife made somewhere other than Tosa and simply think, “That looks cool.”
Perhaps that is exactly what makes Japanese knives so interesting.
Tosa Knives and Japan’s Different Knife-Making Regions
Japanese knives do not come from one single tradition. Different regions developed their blade-making industries through different histories, local industries and demands.
Sakai became particularly famous for traditional Japanese kitchen knives and its division of specialised work between forging, sharpening and handle fitting. Echizen developed its own distinctive blade-making tradition, while Sanjo became known for a broader culture of metalworking and forged tools.
Tosa also followed its own path.
Surrounded by mountains and historically connected to forestry, agriculture and practical tools, Tosa developed a strong culture of forged blades designed to work.
That background is one reason I find Tosa Knives fascinating. There is often something practical and straightforward about them. They can show the marks and character of handmade production rather than trying to hide every sign of the process.
There are people who care deeply about where their knives come from. Some may specifically want a knife from Sakai. Others may love Echizen knives, Sanjo craftsmanship or Tosa Knives.
There is nothing wrong with that.
Other people choose according to purpose. They may prefer one type of knife for sashimi, another for vegetables and something completely different for everyday preparation.
That is something I understand very well as a chef.
Steel also changes the experience. Carbon steels such as Aogami can feel completely different from stainless steels such as Ginsan, VG10 or powder metallurgy steels such as SG2.
One of the most interesting things I have learned since I started selling Tosa Knives is how difficult it is to predict what someone will like.
When I visit people and show them knives, some show almost no interest in Tosa at all.
Others immediately become curious.
Sometimes I look at someone and think, “This is probably the knife they’re going to choose.”
Then they pick something completely different.
Maybe they like the handle. Maybe they prefer the blade shape. Maybe the weight feels right. Sometimes there probably isn’t even a logical explanation.
Tosa Knives Are My Business — But They Don’t Have to Be Everyone’s Favourite
Of course, I want people to discover Tosa Knives.
I work directly with people in Tosa because I respect the craftsmanship, history and practical character behind these knives, and I want more people in Australia to know about them.
But I don’t believe I need to say that every Tosa knife is automatically better than every knife made somewhere else in Japan.
There are incredible knives being made across Japan.
And I still see knives from other regions and think they are beautiful.
For me, appreciating another knife doesn’t make Tosa any less special.
It makes Japanese knife culture more interesting.
Maybe the Most Important Choice Isn’t the Region
So, are Tosa Knives better than knives from Sakai, Echizen, Sanjo or somewhere else?
I don’t think that is the question I want to answer.
Choosing a knife is personal.
Since becoming a knife seller, that has become clearer to me every time someone chooses a knife I didn’t expect them to choose.
Maybe my job isn’t to convince everyone that Tosa is the best knife-making region in Japan.
If wonderful knives are being made all across Japan, then perhaps my challenge is something different.
I want to become the kind of person someone thinks:
“I want to buy my knife from him.”
I’m still a chef, and I’m still learning as a knife seller.
I sell Tosa Knives because I genuinely believe in them. I want to share their history, their craftsmanship and the people behind them with Australia.
But ultimately, I hope people choose the knife that makes them want to pick it up and cook.
And if one day that knife happens to be a Tosa knife from Asaoya Yaichi, I’ll be very happy.
When I started looking deeper into Tosa knife history, I became curious about something I had never really thought about before.
We often talk about how Tosa blades were forged, the blacksmiths who made them, and the traditions that survived for hundreds of years. But after researching the history of Tosa knives recently, another simple question came to mind:
How did these blades actually get from the blacksmiths of Tosa into the hands of people elsewhere in Japan?
I sell Tosa knives in Australia today, yet I honestly did not know much about how Tosa blades were distributed in the past. So, as with many of the subjects on this blog, I decided to look it up.
Tosa Knife History Started With More Than Kitchen Knives
One thing that becomes clear when researching Tosa knife history is that we should not imagine Tosa as simply a historical kitchen-knife production area.
Kochi Prefecture, historically known as Tosa Province, has long been closely connected with forestry. Its warm, rainy climate supported extensive forests, and timber became an important resource.
Working in those forests required cutting tools.
Axes, hatchets, sickles and saws were essential working tools, and the demand for agricultural and forestry blades helped Tosa’s blacksmithing industry develop. During the early Edo period, policies encouraging forestry and the development of new farmland increased this demand significantly.
In other words, these blades were not originally objects made to sit beautifully in a display case. They were tools made to work.
This was the part I found particularly interesting.
Tosa’s blade industry developed alongside its timber industry. One example is the Tosa saw. Historical information from the Tosa Cutlery Distribution Center explains that Tosa saw production developed around Kataji, an area along the Monobe River that served as a gathering point for timber.
So there was a natural relationship between the forests, the workers, the movement of timber and the tools required to work with it.
As Tosa’s forestry culture developed, its blades gained a reputation as practical working tools.
Some accounts also describe forestry workers carrying Tosa-made tools when travelling to work in other regions. Other workers saw and used these blades, helping their reputation spread beyond Kochi.
That is very different from modern marketing.
There was no Instagram, online advertising or SEO. A tool could build its reputation simply because someone used it every day and trusted it.
By the Meiji period, the distribution story becomes clearer.
Historical accounts of the Tosa blade industry indicate that around 1887, sales routes had expanded beyond the local area. They later spread throughout Shikoku and into the Chugoku region of western Honshu.
As this happened, wholesalers dealing in forged blades began to develop, creating a more organised distribution system.
I found this fascinating because it shows a transition.
A blade could begin in a small workshop, pass through merchants and wholesalers, and eventually reach users far beyond the place where it had been forged.
The blacksmith did not necessarily need to travel across Japan himself. A distribution network was beginning to connect regional craftsmanship with a much larger market.
Tosa Knife History Was Built Around Practical Tools
The more I read about Tosa knife history, the more I feel that practicality is one of the keys to understanding Tosa blades.
Their reputation was not created only by beautiful craftsmanship.
These were blades expected to cut wood, clear land, harvest crops and perform demanding everyday work. Kitchen knives later became an important part of the tradition, but they belong to a much broader culture of forged working tools.
Perhaps that is one reason I personally find Tosa knives so appealing.
They can be beautiful, but they were never supposed to be beautiful only.
And this is where researching the past made me think about what I am doing today.
Hundreds of years ago, Tosa blacksmiths made blades for people working in the forests, farms and kitchens of Japan. Over time, those blades travelled farther through workers, merchants and developing distribution networks.
Today, the distance is much greater.
I work directly with Ishizuchi Kanamono Seisakusho and bring handcrafted Tosa knives from Japan to Australia.
Of course, modern shipping and online stores make distribution completely different. But when I look at the bigger picture, perhaps the basic idea has not changed as much as I expected.
A blacksmith makes a tool.
Someone believes in that tool.
And then someone carries it to the next person who will use it.
I did not know much about this side of Tosa knife history before researching it. Now, every time I unpack a shipment of Tosa knives here in Australia, I think I may be participating in a very small continuation of a journey that began long before me.
When you work with something every day, sometimes you forget to ask where it actually came from.
I sell Tosa knives in Australia, sourcing handcrafted Japanese knives directly from Shikoku, Japan. I have also spent more than 25 years working as a chef in Japan and Australia. I know how these knives feel in the hand, how they sharpen, and how they perform in a professional kitchen.
But recently, I realised there was something I wanted to understand better.
How did Tosa knives actually begin?
I knew that Tosa had a long history of blacksmithing, but I wanted to look deeper into why this particular part of Japan became known for forged blades. What I found made me appreciate the history behind these knives even more.
The story of Tosa knives is closely connected to the geography and working life of Kochi Prefecture, historically known as Tosa Province.
Kochi is a mountainous region with extensive forests. For generations, forestry was an important part of life there, and people needed strong, dependable tools for cutting trees, clearing land and working in the mountains.
That naturally created demand for forged tools such as axes, hatchets, sickles and saws.
The history, however, goes back even further.
Sword-making techniques are said to have reached Tosa during the Kamakura period. By 1590, the Chōsokabe Land Survey Records documented 399 blacksmiths in Tosa Province.
That number surprised me.
It shows that blacksmithing was already deeply established in the region more than 400 years ago.
How Tosa Knives Grew With Forestry and Agriculture
The major development of Tosa forged blades came during the early Edo period.
In 1621, reforms by the Tosa Domain encouraged the development of forestry and new agricultural land. As forestry and farming expanded, so did the need for reliable cutting tools.
Blacksmiths responded to that demand.
Over time, production increased and techniques improved. What began as tools essential for daily work gradually developed into what we now recognise as the tradition of Tosa Uchihamono, or Tosa forged blades.
This is one thing I find particularly interesting about Tosa.
The tradition was not created simply to make beautiful objects.
These were working tools.
They had to cut. They had to survive hard use. And they had to be practical enough for people who depended on them for their livelihood.
Another characteristic that caught my attention while researching Tosa knives was something known as jiyū tanzō, or “free forging.”
Rather than relying entirely on fixed moulds, Tosa blacksmiths traditionally forged different shapes and sizes according to their intended purpose.
That flexibility made sense in a region where people needed many different kinds of blades for forestry, agriculture and everyday life.
Even today, you can see something of that character in handcrafted Japanese knives.
Small differences in hammer marks, blade shape and finish are not necessarily imperfections. To me, they are reminders that a knife was made by human hands rather than simply coming from an automated production line.
In 1998, Tosa Uchihamono was officially designated as a Traditional Craft of Japan. The tradition includes not only kitchen knives but also axes, sickles, hatchets, saws and other working blades.
Modern Japanese kitchen knives have naturally evolved as well.
Today we can find traditional carbon steels such as Aogami alongside stainless steels and modern powder metallurgy steels. Handles, finishes and blade styles have changed to suit contemporary cooks, but the connection between Japanese knife making and traditional forging remains.
After looking into this history, I see the knives I work with a little differently.
I started Asaoya Yaichi because I wanted to bring genuine handcrafted Japanese knives from Shikoku to Australia. As a chef, my first concern will always be practical: does the knife actually work well in a kitchen?
But there is another side to it.
Learning about Tosa knives reminded me that Japanese blades did not develop only as kitchen tools. Their history is connected to forestry, agriculture, sword-making knowledge and generations of blacksmiths adapting their skills to what people actually needed.
That history does not automatically make every knife perfect.
But I think understanding where these traditions came from gives us a better appreciation of why Japanese forged knives are the way they are today.
Perhaps that is what I like most about the history of Tosa.
These blades were never meant to exist only behind glass.
They were made to be used.
And more than 400 years later, that practical spirit can still be found in the Japanese forging traditions that continue across Shikoku today.
I still remember one of my earliest experiences with a Japanese knife burr.
I had only recently started working as a chef, and like every young cook, I was learning how to sharpen my own knives. One day, while sharpening, a tiny piece of metal suddenly came off the edge.
I looked at it and genuinely thought part of my knife blade had broken away.
So I went to the head chef and said something like, “Chef, part of the blade just came off. Is this okay?”
I can still remember his face.
He looked at me as if he was thinking, What on earth is this guy talking about?
Looking back now, it makes me laugh.
The blade had not fallen off at all.
What I had seen was a Japanese knife burr coming away from the edge.
After more than 25 years working as a chef in Japan and Australia, I have sharpened countless knives since then. But recently I realised something: although I had learned to recognise a burr through experience, I had never really stopped to investigate what it actually is.
When sharpening a knife on a whetstone, we are removing a very small amount of steel from the blade. As the abrasive surface of the stone works against the steel, the geometry of the edge gradually changes until the sharpening reaches the very apex.
At that point, extremely thin metal at the edge can be pushed over to the opposite side. This thin, folded-over material is what we commonly call a burr.
In Japanese sharpening, it is often referred to as kaeri (返り), or ha-gaeri (刃返り).
That tiny piece of metal I saw as a young chef was therefore not my knife mysteriously losing its cutting edge. It was material created during the sharpening process.
If somebody had explained that to me at the time, I probably would not have asked my head chef whether my blade had fallen off.
But making mistakes is often how we remember things.
A Japanese knife burr can be useful because it gives us information about what is happening at the edge.
If you sharpen one side and eventually detect a burr along the opposite side, it generally indicates that your sharpening has reached the apex in that area.
But there is an important distinction.
Creating a huge burr is not the goal of sharpening.
When I was younger, I sometimes thought that if I could clearly feel a large burr, I must have sharpened the knife properly. With experience, I learned that continuing to grind away steel simply to make a larger burr is unnecessary.
You are removing steel every time you sharpen.
The purpose is to create a clean, properly formed cutting edge—not to remove as much metal as possible.
This is where sharpening becomes more interesting.
A large Japanese knife burr may actually be a sign that you have continued sharpening longer than necessary. Once the abrasive has reached the apex and a burr has formed, repeatedly grinding the same side can simply produce more deformation and remove more steel.
This connects with something I have learned through my own mistakes.
If you keep sharpening at too high an angle, the geometry around the cutting edge can gradually become thicker. Similarly, using a whetstone that is no longer flat can affect the geometry you are trying to create.
Sharpening is not only about making a knife feel sharp today. It is also about maintaining the blade over many years.
Eventually, that weakened metal needs to be removed cleanly.
Simply leaving a large burr attached can create the impression of an extremely sharp knife at first, but that fragile metal may fold, break away or disappear quickly during use.
This is one reason the finishing stages of sharpening matter.
I normally use a 1000-grit stone for my main sharpening and then move to a 6000-grit stone for finishing. The lighter work at the end is not about aggressively removing more steel. I am refining the edge and reducing what remains of the burr.
The more knives I sharpen, the more I feel that the final light touches are just as important as the earlier grinding.
There is another lesson hidden in that embarrassing story from when I first became a chef.
Nobody starts out knowing how to sharpen.
You can read about angles, steels, whetstones and edge geometry, but eventually you have to put a knife on a stone and learn what is happening through your hands.
Over the years I have used carbon steels, stainless steels and modern high-performance steels, and they do not always feel exactly the same on a whetstone.
That tactile experience is one of the things I still find fascinating about Japanese knives.
More than 25 years after telling my head chef that “the blade came off,” I can finally give my younger self a better answer.
Don’t worry.
The blade didn’t fall off.
It was just the burr.
A Japanese knife burr is useful because it can tell us that sharpening has reached the edge, but producing the biggest possible burr does not mean producing the best possible edge.
For me, that is the real conclusion.
The burr is a sign during sharpening. It is not the goal of sharpening.
And perhaps that is why I still remember that confused look on my head chef’s face all these years later.
After more than 25 years working as a chef in Japan and Australia, I had never really thought seriously about Japanese knife thickness.
Of course, I have used both thin and thick knives. From experience, I have always felt that thinner knives are generally easier to use. They enter ingredients smoothly, require less effort, and simply feel good when cutting.
But I had never really asked myself why.
Since I started selling Japanese knives, I have found myself questioning things I used for years without thinking about them.
This time, the question was simple:
When we say a Japanese knife is “thin,” what part of the knife are we actually talking about?
And does thinner really mean better?
What Does Japanese Knife Thickness Actually Mean?
At first, I assumed knife thickness simply meant the thickness of the spine.
That is certainly one measurement, but it does not tell us everything about how a knife will cut.
A blade changes thickness from the spine down towards the cutting edge. The area immediately behind the edge can have a major influence on how easily the knife passes through food.
When I learned this, it immediately made sense from my experience as a chef.
I have used knives that felt extremely sharp at the edge but somehow required more effort when cutting. I have also used knives that seemed to slip through ingredients almost effortlessly.
The sharpness of the edge was not necessarily the only difference.
A simple cross-section diagram helped me understand this surprisingly well.
Imagine two sharp blades entering the same ingredient. One remains relatively thin behind the cutting edge, while the other becomes thick very quickly.
The thinner blade can continue through the food with less resistance. With the thicker blade, the sides of the blade begin pushing against the ingredient and forcing it apart.
Both edges may be equally sharp, but they can feel completely different in actual use.
This is why Japanese knife thickness is not simply about one measurement at the spine. The thickness behind the edge, the shoulders and the taper of the blade all contribute to how it moves through food.
For someone like me who spent years judging knives mainly by how they felt in my hand, it was interesting to finally understand part of the reason behind that feeling.
I also wondered whether there was a particular measurement where a Japanese knife officially becomes thin.
There really isn’t one simple number.
A measurement such as 2 mm at the spine can be useful, but where that measurement is taken matters. A blade may also become progressively thinner towards the tip.
Two knives with similar spine thickness can therefore feel very different if their geometry behind the edge is different.
The purpose of the knife matters too.
A gyuto and a deba should not have the same geometry simply because thinner sounds better. Japanese knives developed into different shapes because they were designed for different jobs.
This was probably the most important thing I learned.
A thin blade can reduce resistance through food, but that does not mean every knife should be made as thin as possible.
Thickness also provides strength and stiffness.
A deba, for example, needs enough strength for working around fish bones and joints. Making it extremely thin would defeat part of the purpose of the knife.
So instead of asking only:
“How thin is this knife?”
I think the better question is:
“Is this knife thin enough for its purpose while still having the strength it needs?”
Recently, I have been researching steels such as Ginsan, VG10 and SG2.
Steel is obviously important, but looking into Japanese knife thickness reminded me that the steel name alone cannot tell us how a knife will actually feel when cutting.
This part is not something I only learned while researching this article.
I have actually experienced it myself — partly because I can be a little lazy with sharpening.
If I keep sharpening a knife at too steep an angle, I can still create a sharp edge. But over time, the geometry around the edge can become thicker.
The knife may feel sharp when I test the edge, yet it does not pass through food as easily as it once did.
I have also made a similar mistake by continuing to use a whetstone after it had become dished instead of flattening it properly.
I knew I should flatten it.
Sometimes I just didn’t.
That uneven stone affected the way I was sharpening, and eventually the knife did not feel the same.
So when I read about thickness behind the edge and blade geometry, I thought:
I’ve done this to my own knives.
That experience taught me something important. Sharpening is not only about making the very edge sharp. Maintaining the geometry behind the edge matters too.
These days, I pay much more attention to keeping my stones flat and to the angle I am sharpening at.
Sometimes the best lessons come from doing it wrong yourself.
So, Do I Think Thinner Japanese Knives Are Better?
After looking into all of this, I wanted to give myself a clear answer.
Is a thinner knife a better knife?
My answer is:
Not always. But for most of the everyday kitchen knives I use, I still prefer a thinner blade.
Before I understood the geometry, I already knew from experience that thinner knives often felt easier to use. They entered ingredients more smoothly and required less effort.
Now I understand more about why.
Of course, I would not want a deba to be as thin as a light vegetable knife. Different knives need different levels of strength, weight and stiffness.
But if I am choosing a gyuto, santoku or sujihiki for everyday work, I personally prefer a blade that feels thin and moves through food with as little resistance as possible.
So after more than 25 years using knives professionally, this is my conclusion:
Thin does not automatically mean better. But if a knife can keep the strength required for its job, I prefer it thin.
Maybe my hands already knew that long before I understood the reason.
I have worked as a professional chef for more than 25 years, but honestly, I cannot say with certainty whether I have ever used an SG2 steel knife.
I may have used one without even knowing it.
For most of my career, I did not choose knives by looking closely at the name of the steel. What mattered to me was much simpler: how the knife felt in my hand, how it cut, how it sharpened, and whether I could rely on it during service.
Since becoming involved in Japanese knives from the selling side, however, I have started asking questions that I never really asked as a chef.
SG2 steel was one of them.
I knew the name and knew it had a reputation as a premium Japanese knife steel. But one description caught my attention more than anything else:
Powder steel.
Why would steel used for a kitchen knife be made from powder?
SG2 steel, also known as Super Gold 2, is a Japanese powder metallurgy steel used in high-performance kitchen knives.
Takefu Special Steel lists Super Gold 2, or SPG2®, as a powder steel. Interestingly, while the company publishes representative chemical compositions for steels such as VG10, the composition of SPG2® is currently listed as non-disclosed.
That is worth mentioning because there are many exact SG2 chemical compositions repeated online. Rather than treating those figures as official specifications, I prefer to stick with what the manufacturer itself currently publishes.
But what interested me most was not the exact percentages.
The term “powder steel” can sound strange if, like me, you spent most of your career thinking about knives as finished tools rather than thinking about how their steel was produced.
Powder metallurgy uses a different manufacturing route from conventional steelmaking. Molten metal can be atomised into extremely small particles, creating metal powder that is subsequently consolidated and processed into usable material.
One of the important advantages of this approach is greater control over the distribution of alloying elements and the structure of the resulting material.
That was when powder steel started making more sense to me.
It is not simply ordinary finished steel being ground into dust and somehow glued back together.
The powder is part of a sophisticated metallurgical process designed to create a highly controlled material.
For someone who spent years worrying about what happened to a knife after it arrived in the kitchen, it is fascinating to start looking at what happens long before a blacksmith begins making the blade.
SG2 steel is commonly used in Japanese knives with relatively high hardness. Many SG2 knives on the market are specified around HRC 62–63, although the exact hardness depends on the maker and heat treatment.
This can allow a well-made blade to take a very fine edge and maintain that edge for a long time.
But this is also where I think steel discussions can become misleading.
A high HRC number does not automatically make a great knife.
Steel is only one part of the finished tool.
Blade geometry, thickness behind the edge, heat treatment, sharpening, balance and the skill of the maker all influence how a knife actually performs.
After working with knives for more than 25 years, I trust what happens on the cutting board more than a specification written on a product page.
SG2 Steel Does Not Automatically Mean Better Cutting
This is particularly important when comparing SG2 steel with other Japanese knife steels.
It is tempting to look at SG2, VG10, Ginsan, Aogami or Shirogami and try to put them into a simple ranking from best to worst.
I do not think knives work that way.
Two knives made from the same steel can feel completely different because their geometry, heat treatment, weight, balance and sharpening are different.
And two chefs can use the same knife and prefer completely different things.
For most of my career, I did not know the detailed composition of the steel in my knives. I knew whether I liked using them.
That experience has not suddenly become meaningless just because I now know more steel names.
If anything, learning about steel has made me realise how many different factors come together to create what we simply call “cutting feel.”
SG2 steel is often positioned above VG10 in the Japanese knife market, particularly in premium knives.
That does not necessarily mean someone using a VG10 knife should immediately replace it with SG2.
I have used VG10 extensively, and I know from experience that a properly sharpened VG10 knife can perform extremely well.
SG2 is different for me because I cannot honestly claim the same personal experience.
Perhaps I have used it. Perhaps I have not.
After more than 25 years in professional kitchens, there are plenty of knives I used without ever asking what steel was inside them.
So rather than pretending I can give a definitive chef’s comparison between SG2 and VG10, I would rather say this:
SG2 interests me enough that now I want to deliberately use one.
Would I Notice SG2 Steel Now?
This is probably the question that interests me most.
If I unknowingly used an SG2 knife 15 or 20 years ago, would I have noticed?
Maybe.
But I probably would not have thought, “This must be powder metallurgy steel.”
I would have thought about how it cut, how long the edge lasted and what happened when I put it on a whetstone.
Today I would approach it differently.
Now that I understand a little more about what SG2 steel is and why powder metallurgy exists, I would like to deliberately use an SG2 knife and see what I actually notice in real kitchen work.
Maybe the edge retention will immediately stand out.
Maybe sharpening will feel different.
Or maybe blade geometry and sharpening will still influence my impression more than the name of the steel.
Researching SG2 steel reminded me of something that has happened repeatedly since I started looking more deeply into Japanese knives.
The more I learn, the more I realise how many things I simply never thought about as a chef.
For years, a knife was a tool.
If it cut well, sharpened well and survived professional kitchen work, I was happy.
Now I find myself going backwards from the finished knife to the steel, the manufacturing process, heat treatment and the people who eventually turn that material into a blade.
Does knowing all of this automatically make someone a better cook?
Of course not.
But it has definitely made me appreciate Japanese knives differently.
And perhaps one day soon, I will knowingly use an SG2 knife for the first time.
Or maybe it will only be the first time I actually know what I am using.
I had used VG10 Japanese knife steel for years before I ever stopped to ask a very simple question: what does VG10 actually mean?
After more than 25 years working as a chef in Japan and Australia, I knew VG10 as a practical stainless steel used in many Japanese knives. I knew how it felt on the cutting board, how it responded to sharpening, and how convenient stainless steel could be in a busy kitchen. But if someone had asked me what the letters meant, why cobalt was in it, or exactly what made VG10 different from other stainless steels, I probably would not have had a very good answer.
Since starting a Japanese knife business, I have found myself asking questions I never really thought about as a chef.
So this time, I became curious about VG10 and decided to look into it.
VG10 Japanese Knife Steel: What Does the Name Actually Mean?
One of the first things I discovered was that this apparently simple question was not quite as straightforward as I expected.
VG10 is an original blade steel produced by Takefu Special Steel in Echizen, Fukui Prefecture, Japan. On the manufacturer’s Japanese website, the steel is identified as V金10 (VG10), or “V Kin 10.” Takefu also produces other steels in the same family, including VG1, VG2, VG5 and VG7.
When I started searching for what the letters “VG” actually mean, I found several different explanations online. However, I could not find a clear statement on Takefu Special Steel’s official VG10 page defining the letters in the same way.
What I could confirm was that VG10 is a Japanese stainless blade steel produced by Takefu Special Steel and officially identified in Japan as V金10 (VG10).
In the end, I did not find a definitive answer to exactly what “VG” stands for from the manufacturer’s information I checked. That was also one of the things I learned by looking into it.
This was the part that made me realise how little I had thought about the steel itself.
According to Takefu Special Steel, representative values for VG10 include approximately 1.00% carbon, 15.00% chromium, 1.00% molybdenum, 0.25% vanadium and 1.55% cobalt.
I had heard the word “cobalt” many times before. But then I had another very simple question:
What exactly is cobalt?
Cobalt is a metallic chemical element, represented by the symbol Co. In VG10 Japanese knife steel, it forms part of an alloy containing several different elements, each contributing to the characteristics of the finished steel.
Takefu explains that chromium, molybdenum and cobalt strengthen the steel matrix and help achieve high hardness and long-lasting cutting performance. Vanadium helps refine the microstructure, while chromium, molybdenum and vanadium contribute to hard carbides that improve wear resistance.
Suddenly, a steel I had simply called “VG10” for years became much more interesting.
On paper, VG10 has a combination of characteristics that makes a lot of sense for kitchen knives.
Takefu Special Steel lists excellent corrosion resistance and sharpness among its qualities and says the steel is used not only for kitchen knives but also for general-purpose knives and machine blades. The manufacturer also describes VG10 as having good machinability and being relatively easy to sharpen.
That combination is important in a real kitchen.
A kitchen knife gets wet. It touches acidic ingredients. It gets sharpened repeatedly. In a professional kitchen, it may be used for hours during a single service.
For many cooks, having good edge performance while avoiding some of the maintenance required by traditional carbon steel is an attractive balance.
That helps me understand why VG10 Japanese knife steel has become such a familiar name in Japanese kitchen knives around the world.
VG10 Japanese Knife Steel From a Chef’s Perspective
Here I can look at VG10 from the perspective I know best: actually using knives.
I have spent more than 25 years using knives, sharpening them and working with them in professional kitchens. From that experience, I can understand why VG10 became so popular.
I have used both carbon steels and stainless steels over the years, and I do not believe the name of the steel alone determines whether a knife is good.
Blade geometry, heat treatment, sharpening, construction and the person actually using the knife all make a difference.
A well-made and properly sharpened VG10 knife can be an excellent professional tool.
At the same time, two knives made from the same VG10 steel can still feel very different in the hand and on the cutting board. The steel is an important part of a knife, but it is only one part of the whole knife.
That is something years in professional kitchens taught me long before I started looking into steel compositions.
One thing I enjoy about running Asaoya Yaichi is that it has made me curious about knives all over again.
For most of my career, I did not stand in a kitchen thinking about chromium percentages, vanadium or cobalt. I thought about whether my knife was sharp, whether it felt right, whether I could control it, and whether it could handle the work I needed it to do.
Now I find myself asking why.
Why is it called VG10?
Why does it contain cobalt?
Why do different steels feel different on the sharpening stones?
Why can two knives made from supposedly similar materials feel different when you actually use them?
Once I started looking into these questions, I found that one answer often led to another question.
And perhaps that is one of the most interesting things about learning more about Japanese knives.
VG10 Japanese knife steel was something I thought I understood simply because I had used it for years.
But once I started looking into it, I discovered there was much more behind those three characters than I had ever considered.
Learning about chromium, molybdenum, vanadium and cobalt does not change the experience I have gained from actually using knives. Instead, it gives me another way to understand and appreciate a tool I have spent most of my working life holding.
For years, I looked at knives mainly through the eyes of a chef.
Now, running Asaoya Yaichi has given me another reason to keep asking questions about them.
Sometimes a very basic question can lead somewhere surprisingly interesting.
And this time, it started with just three characters:
For more than 25 years as a chef in Japan and Australia, I have used many different Japanese knives. But when it came to Ginsan Japanese Knife steel, my knowledge was surprisingly simple: I knew Ginsan was stainless steel, and that was about it.
Since starting Asaoya Yaichi, I have become much more curious about the steels behind the knives I use and sell. I recently looked deeper into Aogami and Shirogami, and this time I wanted to understand Ginsan.
Why is it called Ginsan? Is it really stainless? Can it still rust? And why is it sometimes compared with carbon steel?
Ginsan is commonly known as Gingami No.3, or Silver Paper No.3. It is a Japanese stainless cutlery steel from the Yasugi Specialty Steel family.
Just as Aogami means “Blue Paper” and Shirogami means “White Paper,” Gingami means “Silver Paper.” The names come from the identification system traditionally used for these different steels. Despite the name, it does not mean that silver is added to the blade.
Ginsan contains roughly 1% carbon and around 13–14% chromium. The chromium gives it significantly more corrosion resistance than traditional carbon steels such as Aogami and Shirogami.
A Ginsan Japanese Knife is much more resistant to corrosion than a carbon steel knife, but water, salt or acidic food residue left on the blade for long periods can still cause problems.
This distinction is important. “Stainless” is better understood as stain-resistant, rather than a guarantee that the knife can never rust.
For a professional kitchen, however, that extra resistance can make a big difference. Fish, citrus, onions, tomatoes, salt and moisture are all part of everyday work.
This is where Ginsan became much more interesting to me.
When people hear “stainless knife,” they may imagine an ordinary, relatively soft kitchen knife. Ginsan does not really fit that image.
It can be hardened to levels suitable for high-quality Japanese knives and is also known for being relatively pleasant to sharpen compared with some highly alloyed stainless steels.
As someone who has sharpened my own working knives for many years, this matters to me.
Eventually, every knife needs sharpening. How the steel responds to the stone, how easily you can bring the edge back, and the edge you can create are more important in everyday work than simply reading specifications.
I do not think this comparison should be about deciding which steel is “better.”
Aogami, Shirogami and Ginsan each have different characteristics.
Traditional carbon steels can take fantastic edges and can be very enjoyable to sharpen, but they demand more attention. They react to moisture and acidic ingredients, develop patina and can rust quickly if neglected.
Ginsan offers another approach.
It combines stainless corrosion resistance with some characteristics that people appreciate in traditional Japanese knife steels, particularly sharpness and sharpening response.
That is probably why Ginsan is sometimes described as a stainless steel for people who like carbon steel.
Both Ginsan and VG10 are stainless steels commonly used in quality Japanese knives, but their compositions are different.
Ginsan has a relatively simple composition based mainly around carbon and chromium. VG10 is more highly alloyed and also contains elements such as molybdenum, vanadium and cobalt.
That does not mean one is automatically better.
I have used VG10 professionally and know how capable it can be. Ginsan simply offers a different balance.
After more than 25 years working with knives, I believe the steel name alone cannot tell you how good a finished knife will be. Heat treatment, blade geometry, thickness, grinding and sharpening all matter.
After learning more about it, I can understand why Ginsan is popular with both professional cooks and serious home users.
Professional kitchens demand practicality. You may be cutting fish one minute, vegetables the next, washing your knife and immediately moving on to another job.
A steel combining high cutting performance with good corrosion resistance makes a lot of sense in that environment.
For home cooks, the same qualities can be attractive. Not everyone wants to worry about wiping a carbon steel blade immediately after cutting every ingredient.
A Ginsan Japanese Knife offers the possibility of excellent sharpness with easier everyday maintenance.
Before researching this article, my understanding was basically:
Ginsan = stainless steel.
That was about it.
And after more than 25 years as a chef, I am perfectly comfortable admitting that.
For most of my career, I cared more about whether a knife actually worked than memorising the chemical composition of its steel. I sharpened knives, used them and developed my preferences through experience.
Starting Asaoya Yaichi has made me look deeper.
I now understand why Ginsan occupies such an interesting position among Japanese knife steels. It provides corrosion resistance and easier maintenance while still offering the characteristics expected from a high-quality Japanese knife.
But the biggest thing I keep learning is that the steel name is only the beginning.
A Ginsan Japanese Knife can be excellent, but heat treatment, geometry, grinding, sharpening and the skill of the people making it ultimately determine what that steel becomes in your hand.
And now, at least, when someone says “Ginsan,” I know a little more than simply:
After more than 25 years working as a professional chef in Japan and Australia, I have used Japanese knives for most of my working life. But when it comes to Japanese Knife Finishes, I recently realised there was a lot I had never really thought about.
I have used Kurouchi and Damascus knives, and I have even polished one of my own knives to a near-mirror finish. I have also spent many years using traditional Yanagiba and Deba, including an old Yanagiba passed down to me by my mother.
Of course, I knew these knives looked different. But I never really stopped to ask why.
Does a hammered finish actually help food release? Is Kurouchi practical or mainly traditional? Does a mirror-polished blade perform differently?
Since starting a Japanese knife business, I have begun looking at knives from a different perspective. So once again, I decided to do some research.
The first thing I learned is that Japanese Knife Finishes are not all created for the same reason.
Some come directly from the knife-making process, while others involve additional polishing, hammering or decorative work. Some can also influence how food contacts the side of the blade.
But one thing became clear very quickly: the finish alone does not determine how well a knife cuts or releases food.
Blade geometry, thickness, grind, sharpening, the ingredient and even cutting technique can all make a significant difference.
Thinking back over my career, this makes sense. I have always noticed the edge, geometry, weight and balance of a knife far more than its surface finish.
Kurouchi is one finish I definitely know from experience.
The dark surface is associated with the forging process and is intentionally left on parts of the blade instead of being completely polished away.
Years ago, however, I didn’t appreciate it.
I had a Kurouchi knife and decided I wanted it shiny, so I removed the black surface and polished the blade myself.
At the time, I thought it looked better.
Today, I probably wouldn’t do it.
I now appreciate the rustic appearance and character of Kurouchi much more. The remaining oxide layer can also offer some protection to the covered carbon-steel surface, although exposed carbon steel and the cutting edge still require proper care.
Tsuchime is the familiar hammered finish, while Nashiji has a subtler textured surface often compared to the skin of a Japanese pear.
The idea that these textures can help food release makes sense. An uneven surface changes the contact between the food and blade and, in some cases, can reduce the tendency for food to cling tightly to it.
But I learned that it isn’t as simple as saying:
“Tsuchime means food doesn’t stick.”
Blade geometry still matters enormously.
Two knives with similar finishes can behave very differently depending on their grind, thickness and overall shape.
This was interesting to me because it showed that Japanese Knife Finishes can have a practical function without necessarily being the main reason a knife performs well.
Migaki refers to a polished finish, although the degree of polishing varies between makers.
Mirror polish takes that idea much further.
I understand the attraction because I used to love shiny knives. I have spent plenty of time polishing a blade myself until it became highly reflective.
But a smoother surface doesn’t automatically mean better performance. Moist or starchy ingredients can still cling to a smooth blade, and after years in professional kitchens, I have also become much less worried about scratches.
A working knife is going to look like a working knife.
Damascus is another finish I have actually used. The layered patterns can be beautiful, but the pattern itself doesn’t automatically make a knife sharper.
In many modern Japanese knives, Damascus layers form the cladding around a core steel. The core steel, heat treatment, blade geometry and sharpening have a much more direct relationship with cutting performance.
I still love the appearance of a beautiful Damascus blade. I just wouldn’t say, “It’s Damascus, so it must cut better.”
Researching Kasumi was particularly interesting because I have used traditional Yanagiba and Deba for many years.
One of my Yanagiba was passed down to me by my mother and has been used for decades.
But I don’t want to pretend that I spent those years analysing its finish.
I didn’t.
To me, it was simply a traditional Japanese working knife. I sharpened it, maintained it and used it.
Only after becoming involved in selling Japanese knives did I start paying more attention to terms such as Kasumi and the manufacturing and polishing techniques behind traditional blades.
Sometimes there is a big difference between knowing how to use something and understanding exactly how it was made.
After looking more closely at Japanese Knife Finishes, I don’t think there is one “best” finish.
Some finishes may influence food release or surface protection. Some reflect traditional manufacturing methods. Others involve considerable extra craftsmanship and are valued partly for their beauty.
But I would never choose a knife based on finish alone.
After more than 25 years as a chef, I still pay more attention to blade geometry, sharpening, weight, balance and how the knife actually feels in my hand.
What surprised me most was realising that I had used some of these finishes for decades without really thinking about why they existed.
Starting Asaoya Yaichi has made me curious about things I once simply accepted.
And sometimes, researching something I thought I already understood reminds me just how much there still is to learn about Japanese knives.
Aogami and Shirogami are two traditional Japanese carbon steels that I only started learning about after entering the Japanese knife business.
I have worked as a professional chef for more than 25 years, but I have a confession to make.
Until I started selling Japanese knives, I didn’t even know what Aogami and Shirogami were.
To be honest, I didn’t know there were so many different types of stainless steel either. VG10, Ginsan, SG2… I had used knives for years without paying much attention to what the steel was actually called.
And even now, I’m still learning what makes each steel different.
As a chef, I had always judged a knife in a much simpler way. Does it cut well? How does it feel in my hand? How does it feel on the whetstone? And does it work well for the job I need it to do?
Then, after starting my knife business, I kept seeing the words Aogami and Shirogami.
Blue Paper Steel. White Paper Steel.
And one day I thought:
Why blue? Why white?
I honestly had no idea.
So I decided to look it up.
1. Why Are Aogami and Shirogami Called Blue and White Paper Steel?
The names Aogami and Shirogami come from the coloured paper traditionally used to distinguish different grades of Yasugi Specialty Steel.
“Ao” means blue in Japanese, while “Shiro” means white.
That is why Aogami became known as Blue Paper Steel and Shirogami as White Paper Steel.
After more than 25 years of using knives, I had never once wondered about this.
Sometimes the simplest questions are the ones we forget to ask.
2. So, What Exactly Is Shirogami?
Once I understood the name, the next question was obvious.
What is actually different about the steel?
Shirogami is a high-purity carbon steel with tightly controlled impurities. Its relatively simple composition allows it to take a very fine edge, and it has a strong reputation for responding beautifully to whetstones.
Of course, it is still carbon steel.
That means moisture, acidic foods and poor maintenance can cause discolouration and eventually rust.
It can also develop a natural patina through normal use.
For someone used to stainless steel, this extra maintenance may seem inconvenient. For others, it is simply part of the character of a traditional carbon-steel knife.
3. How Is Aogami Different from Shirogami?
This is where things started getting more interesting for me.
Aogami contains alloying elements such as chromium and tungsten in addition to carbon. These additions help increase wear resistance and edge retention.
In simple terms, Aogami is designed to maintain its cutting edge well.
The trade-off is that greater wear resistance can also mean more effort when sharpening compared with a simpler carbon steel such as Shirogami.
Before starting a knife business, I never thought about knives in terms of chromium, tungsten or carbon percentages.
I simply knew whether I liked using a knife or not.
Learning about the steel has given me another way to understand some of those differences.
4. Aogami #1, #2 and Aogami Super
Then I discovered that Aogami itself was not just one steel.
There is Aogami #1, Aogami #2 and Aogami Super.
Very simply, the different grades have different carbon and alloy compositions. Aogami #1 has more carbon than #2, while Aogami Super uses additional alloying elements and is known for high hardness and excellent edge retention when properly heat treated.
At first, it is tempting to think that a higher specification must automatically mean a better knife.
But the more I learn about Japanese knives, the less I think that way.
The steel is only one part of the story.
Heat treatment, blade geometry, grinding, sharpening and the skill of the maker can all affect how the finished knife performs.
This was probably my biggest question when I first started learning about Aogami and Shirogami.
Which one is better?
After looking into it, I think that may be the wrong question.
Aogami is well known for edge retention and wear resistance. Shirogami is famous for its sharpening response and ability to take a very refined edge.
But a knife is something we actually use.
How often do you sharpen? What ingredients do you cut? How do you use your knife? Do you enjoy sharpening? How much maintenance are you comfortable with?
And most importantly, how does the knife actually feel when you use it?
After more than 25 years working as a chef in Japan and Australia, there are certain words I have used thousands of times without really thinking about them.
They are simply Japanese knife names that become part of everyday language when you work in a kitchen.
But recently, a very simple question crossed my mind:
Why are these knives actually called that?
I knew what they were designed to do. I knew how they felt in my hand and when I would choose one over another. But when I started thinking about the actual Japanese knife names, I realised there were some origins I had never really investigated.
So, purely because I was curious, I decided to look them up.
And some of the answers were more interesting than I expected.
Japanese Knife Names Often Tell You Something About the Knife
One thing becomes obvious when looking closely at Japanese knife names: many of them are surprisingly practical.
The name may describe the ingredient, the shape of the blade, or the type of work the knife was intended to perform.
That makes sense.
Traditional Japanese knives were not originally created because someone needed another product for a catalogue. They developed as working tools for particular jobs.
Santoku is probably one of the best-known Japanese knife names outside Japan.
The kanji are:
三 — three 徳 — virtue or merit
So 三徳 literally means something close to “three virtues.”
Today, the Santoku is regarded as an all-purpose Japanese kitchen knife. One common explanation connects those “three virtues” with its ability to handle several major categories of food, often described as meat, fish and vegetables.
The Santoku itself is relatively modern compared with traditional Japanese specialist knives. It developed as Japanese eating habits and home kitchens changed, combining characteristics suited to a broader range of everyday ingredients.
That is probably why the name feels so appropriate.
It is not a knife devoted to one narrow task.
Its strength is versatility.
After years in professional kitchens, I can understand why the Santoku became so popular. For someone who wants one practical Japanese knife for everyday cooking, its name describes its character remarkably well.
This is where researching Japanese knife names gets more interesting because not every origin is perfectly clear.
出 means something like to come out, protrude or emerge.
刃 means blade or edge.
There are different explanations surrounding how the name Deba came into use, including an old story connecting the name with a craftsman whose protruding teeth supposedly inspired the term.
It is an entertaining story, but the precise historical origin of the name is not something I would present as absolute fact.
What we do know is what the Deba became: one of the classic Japanese knives for processing fish.
Its thick spine, substantial weight and strong heel make it very different from a delicate slicing knife.
For me, that uncertainty actually makes the name more interesting.
We use the word “Deba” so casually today that it is easy to forget the name itself has travelled through generations of Japanese cooking history.
The long, narrow shape of the knife resembles a willow leaf, giving us the name 柳刃 — “willow blade.”
This is one of those Japanese knife names that makes immediate sense once you see the kanji and the knife together.
The long blade is closely associated with slicing sashimi and other delicate proteins. Rather than using repeated short sawing movements, its length allows a cook to make a long, controlled slicing motion.
As someone who has spent many years working with fish and sashimi, this is where the poetry of the name and the practicality of the tool come together beautifully.
It looks like a willow leaf.
But that elegant shape also has a job to do.
5. Nakiri 菜切 — A Name That Says Exactly What It Does
The Usuba is a traditional Japanese vegetable knife, particularly associated with precise vegetable work.
Although its rectangular profile can look similar to a Nakiri at first glance, traditional Usuba knives are generally more specialised and are strongly associated with professional Japanese cuisine.
The thin cutting geometry makes sense when you consider the precision required for traditional vegetable techniques.
Again, the name does not try to make the knife sound exotic.
筋 can mean sinew, muscle fibre, tendon or line depending on context.
引 means to pull or draw.
The name reflects the knife’s relationship with trimming and slicing meat, particularly working along or removing sinew and connective tissue.
Today, the Sujihiki is widely used as a Japanese slicing knife.
For me personally, this is an especially familiar knife. I have used Sujihiki extensively in professional kitchens, including for fish and slicing work.
And this is another example of how Japanese knife names can outlive their narrow original interpretation.
A modern Sujihiki can do far more than its literal name might suggest.
Japanese Knife Names Are Small Pieces of Culinary History
I started researching this simply because I was curious.
After more than 25 years as a chef, I thought it was funny that I had said these names countless times without stopping to think about where they came from.
And that may be what I enjoyed most about looking into Japanese knife names.
Gyuto remembers the arrival and growth of meat cookery.
Nakiri tells you exactly what generations of cooks used it for.
Yanagiba describes the beauty of its shape.
Usuba describes its thin blade.
Sujihiki remembers the work it was designed to perform.
Santoku reflects versatility.
And Deba reminds us that sometimes the history behind an everyday word is not quite as simple as we assume.
A Japanese knife is a tool.
But its name can also carry a small piece of Japanese food culture, language and history.
I have worked with Japanese knives for most of my professional life, and I am still finding things about them that make me curious.
That is probably why I never get tired of them.
This article started with one very simple thought:
“Why is a Deba called a Deba?”
Sometimes that is enough reason to start looking.
And I think I might have found another series worth continuing.
When you buy a new Japanese knife, it is natural to assume that the sharpness you feel straight out of the box represents the very best that knife can offer.
I used to think the same way.
After more than 25 years working as a professional chef in Japan and Australia, I have handled many different Japanese knives. Yet one thing I have learned through actually using and sharpening them is surprisingly simple: a new Japanese knife does not always reveal its full potential on the first cut.
Sometimes I have picked up a brand-new knife and felt a slight roughness at the edge. It was certainly sharp, but something about the cutting feel made me wonder whether there was more hidden inside the blade.
Then I sharpened it myself.
And it cut better.
That experience changed the way I judge a new knife. Today, I do not necessarily see factory sharpness as the final destination. To me, it is simply the starting point.
1. A New Japanese Knife Is the Beginning, Not the Finish
For a long time, I assumed something very straightforward: if a knife is brand new, surely this must be the sharpest it will ever be.
It sounds logical.
But after sharpening some of my own knives, I realised that this was not always true.
A quality Japanese knife may already have excellent steel, geometry and craftsmanship, but the feeling at the edge can still change depending on how it is sharpened and maintained.
This is one reason I believe it is difficult to judge the true character of a knife from its first few cuts alone.
2. The First Cut Does Not Always Reveal Everything
Sharpness is not only about whether a knife can cut through something.
As a chef, I notice how the edge enters the ingredient, how much resistance I feel and how smoothly the blade continues through the cut.
Occasionally, with a new Japanese knife, I have noticed a slightly rough feeling at the edge. This does not automatically mean that the knife is bad or that there is something wrong with the steel.
It simply tells me that I have not yet discovered everything that knife can do.
This is also why I have always believed that Kireaji — the feeling of sharpness — is something you experience through your hands, not simply something that can be understood from specifications.
3. Sharpening My New Japanese Knife Changed My Perspective
The biggest lesson came when I sharpened a knife myself and realised that I could make it cut better than it did when it was new.
That was an important moment for me.
Until then, part of me had assumed that the manufacturer had already created the ultimate edge. If this was how it cut when new, then perhaps this was simply the maximum performance of that particular knife.
But after sharpening it, the cutting feel improved.
The knife had not changed.
The steel had not changed.
What changed was the edge.
That made me realise that the sharpness of a new Japanese knife should not automatically be treated as a measurement of everything the knife is capable of.
There is another reason I enjoy sharpening my own knives.
Over time, the knife becomes more familiar.
You begin to understand how the steel responds to the stone, how easily the edge comes back and what kind of finish feels right for the work you do.
For me, sharpening is therefore not simply maintenance.
It is part of developing a relationship with the tool.
This is especially important with handcrafted Japanese knives because I do not think of them as disposable kitchen products. A good knife can remain part of your kitchen for many years when it is properly used, sharpened and cared for.
If there is one thing I would tell someone buying a new Japanese knife, it is this:
Do not assume the first cut tells you everything.
Of course, a new knife should cut well. But I would not immediately conclude that its factory edge represents the absolute limit of what the blade can achieve.
Use it.
Learn how it feels.
And when the time comes, sharpen it properly.
You may discover another level of performance that was already waiting inside the knife.
That, to me, is 真価 — Shinka.
After more than 25 years as a chef, I still enjoy discovering what a knife can really do. Sometimes the most satisfying moment is not taking a new knife out of the box.
It is the moment after sharpening it, making that first cut again, and thinking:
Kurouchi Japanese Knives have a distinctive appearance that is immediately recognisable. The dark, almost unfinished-looking surface left from the forging process gives each knife a character very different from a polished blade.
But I have to admit something.
I have used Kurouchi knives for years, but I have never been someone who believes every knife has to be Kurouchi. I like them, I use them, and I appreciate the traditional appearance — but my relationship with Kurouchi has been a little more complicated than that.
In fact, many years ago, I completely removed the Kurouchi finish from one of my knives.
Looking back now, I probably wouldn’t do it the same way again.
The word Kurouchi (黒打ち) literally refers to the black finish commonly seen on traditionally forged Japanese knives. Rather than polishing the entire surface of the blade, part of the dark forge scale is intentionally left on the knife.
This gives Kurouchi Japanese Knives their rustic and unmistakably handmade appearance.
For me, though, the interesting part of Kurouchi isn’t simply how it looks when the knife is new. It is what happens after you actually start using it.
A handmade knife doesn’t stay frozen in the condition in which you bought it. Scratches appear. The blade gets sharpened. Carbon steel develops patina. Handles change with use. And the Kurouchi finish itself can slowly wear and change.
That is part of owning and using a handmade Japanese knife.
At the time, I had become slightly obsessed with mirror polishing knives. I enjoyed taking a blade and seeing just how clean and reflective I could make the surface.
So one day I had an idea.
Why not remove the black finish?
I took the knife to the whetstones and gradually removed all of the Kurouchi.
Every bit of it.
At the time, I was happy with what I had done. I wanted a polished knife, so I made it polished.
But today, I see that knife differently.
If I were doing the same project now, I would probably leave the black Kurouchi finish above the bevel and polish the exposed steel below it to a mirror finish.
The contrast between deep black Kurouchi and bright polished steel would probably look much better.
More importantly, it would preserve part of the original character of the knife.
Sometimes you only learn what you like after doing something the other way first.
This is something I think buyers should understand before choosing Kurouchi Japanese Knives.
They change.
The black finish can gradually wear. Areas that receive more contact may look different from areas that receive less. The appearance may become less uniform than when the knife was brand new.
Whether that is good or bad depends entirely on the person holding the knife.
Personally, I am fine with it.
If a knife changes because I have cooked thousands of meals with it, sharpened it countless times and used it every day, I don’t necessarily see those changes as damage.
They are part of the knife.
It is similar to the way I think about patina on carbon steel. Some people want to remove every mark immediately. Others enjoy watching the blade develop its own appearance through use.
I previously wrote about a chef I knew who loved keeping his knives absolutely spotless. Even a small amount of cloudiness on the blade could bother him.
There is nothing wrong with that.
Some people simply love a perfectly polished Japanese knife.
For someone like that, a Kurouchi knife may not be the best choice.
If you expect your knife to look exactly the same after years of professional use as it did on the day you opened the box, the natural changes of a Kurouchi finish could become frustrating.
This is why I don’t think there is one “best” Japanese knife finish.
The right knife depends on the person.
Some people love mirror polishing. Some love Nashiji. Some love Damascus patterns. Others want the rustic appearance of Kurouchi.
The important thing is understanding what you are buying and choosing something that suits the way you see your tools.
After more than 25 years working as a chef in Japan and Australia, my relationship with knives has changed.
When I was younger, I sometimes wanted a knife to look perfect.
Today, I am much more interested in what happens after years of actually using it.
A scratch doesn’t automatically bother me. A developing patina doesn’t necessarily need to disappear. A handle that has changed slightly through years of work can remind me how much that knife has been used.
And if the Kurouchi finish slowly changes, I can accept that too.
Perhaps that is why I now look back at the sujihiki I completely polished and think I would do things differently today.
I don’t regret experimenting with it. In fact, I’m glad I did.
It taught me something.
A handmade Japanese knife doesn’t always need to be improved, corrected or returned to perfection. Sometimes the changes that happen through use are exactly what give the knife its character.
For me, this is ultimately the attraction of Kurouchi Japanese Knives.
Not because Kurouchi is better than every other finish.
Not because every chef should own one.
And certainly not because a Kurouchi knife will remain perfectly black forever.
I like the fact that it can change.
If the black finish wears in a way that I like, great. If it develops differently from what I imagined, I can still see that as part of the knife’s story.
That attitude won’t suit everyone.
And that’s okay.
A Japanese knife is a personal tool. After years of sharpening, cooking and caring for it, it becomes different from the knife that originally arrived from the blacksmith.
Maybe that is something worth appreciating rather than preventing.
After all, I once removed every trace of Kurouchi from a knife because I thought polished steel looked better.
After more than 25 years working as a professional chef in Japan and Australia, I have used many Japanese knives. But honestly, I have never chosen a knife by specifications alone.
Of course, steel matters. Hardness matters. Blade shape, handle, balance and craftsmanship matter too.
Over the years, I have developed my own preferences. I personally like Aogami steels, for example. From my experience, I find them relatively easy to sharpen and enjoyable to use.
But there is another side to choosing a Japanese knife that is much harder to put into numbers.
That is exactly what happened with this Aogami #2 knife.
I like the polished blade because it does not immediately have the rustic appearance many people associate with carbon steel. Underneath that clean finish, however, is Aogami #2 — a steel I already know and like.
The green Micarta gives it a modern appearance, while the turquoise band adds something completely different.
To my eyes, there is even a little Wabi-Sabi in that turquoise detail. It is unusual without being too flashy, and it gives the knife its own character.
There is also a reason this story matters to me as the person behind Asaoya Yaichi.
When you buy a Japanese knife online, you cannot physically pick up every knife before making your decision.
I understand that.
That is why I believe the selection before a knife appears in the store is important.
I have spent more than 25 years using knives in professional kitchens. When selecting knives for Asaoya Yaichi, I want to actually see them, hold them and look closely at their quality, construction and overall feel.
I do not choose knives simply because a specification sheet looks impressive.
I want to offer knives that I would be happy to own myself.
I do not believe an expensive knife is automatically perfect for everyone, but I do believe good materials, skilled craftsmanship and careful finishing have real value.
Very cheap knives can do a job, but there are usually compromises somewhere.
A quality knife can also change the way you treat it. When you own something you genuinely value, you tend to clean it carefully, sharpen it properly and want to keep it for many years.
Japanese knife sharpness is often described as though it were something simple. A knife is either sharp or it is not. It cuts paper cleanly, shaves hair, or slices through a tomato, and we decide that it is sharp.
But after working as a professional chef for more than 25 years, I have come to feel that sharpness is not quite that simple.
In Japanese, there is a word that expresses something slightly different: 切味 — Kireaji.
Kireaji literally relates to the “cutting feel” of a blade. For me, that is a better way to describe what happens when a knife actually meets food.
Sometimes I sharpen a knife and it seems almost perfect. The blade enters the ingredient effortlessly, as though there is almost no resistance.
Other times, I sharpen what feels like exactly the same way, using the same stones and technique, yet the knife somehow feels heavier through the cut.
It is still sharp.
But it does not feel the same.
And occasionally, I can even feel a slight roughness through the edge.
After all these years of using knives professionally, this still fascinates me.
1. Japanese Knife Sharpness Is More Than “Sharp or Dull”
One of the biggest things I have learned is that Japanese knife sharpness cannot always be explained by a simple sharp-versus-dull measurement.
A knife may easily cut paper and still feel slightly heavy when slicing food.
Another knife may not seem dramatically different in a basic sharpness test, yet when it touches fish, meat or vegetables, the blade seems to glide straight through.
That sensation is difficult to describe until you have experienced it.
For me, this is where the idea of Kireaji becomes useful.
It is not simply whether the edge can cut. It is the resistance you feel as the blade enters the ingredient, the way the knife continues through it, and even the feedback transmitted through the handle into your hand.
Understanding the bevel and edge geometry is an important part of understanding why two sharp knives can feel completely different.
2. Why Japanese Knife Sharpness Can Feel Different After Sharpening
This is something that still surprises me.
I can sharpen the same knife on the same stones using what I believe is the same technique, but the final Kireaji is not always identical.
Sometimes the result is exceptional.
The knife feels incredibly smooth. There is almost no hesitation when the blade touches the ingredient.
Then another day, the knife is definitely sharp, but I feel slightly more resistance.
Why?
There are many possible explanations. The exact sharpening angle may have changed slightly. The burr may have formed differently. The burr removal may not have been identical. Pressure on the stone may have changed without me consciously noticing it.
Even the final refinement of the edge can influence the sensation.
Sharpening by hand contains countless tiny variables.
That is one reason I think sharpening Japanese knives remains interesting even after many years.
3. Japanese Knife Sharpness Can Sometimes Feel Rough
There is another sensation I occasionally notice after sharpening: a slight roughness.
The knife cuts.
It may even cut very well.
But the edge does not feel completely smooth.
This is particularly interesting because it demonstrates the difference between simply achieving an edge and achieving an edge that feels right.
A microscopic burr or differences in edge refinement may contribute to this sensation. The finish produced by the sharpening stone can also influence how the edge interacts with food.
A highly polished edge and an edge with more microscopic “bite” can both be sharp, but they may not feel identical.
And depending on what you are cutting, one may actually feel better than the other.
This is why I do not believe sharpness should always be judged by a single test.
Over the years I have used both carbon and stainless steels, and I do not think every steel produces exactly the same cutting sensation.
Aogami, Ginsan, VG10, SG2 and other steels have different characteristics. Hardness, carbide structure, heat treatment, edge stability and sharpening response can all influence how an edge behaves.
But there is an important point here.
Harder does not automatically mean better Kireaji.
A high HRC number can contribute to edge retention and allow certain steels to support fine edges, but hardness alone cannot describe what the knife will feel like when it passes through a piece of fish.
That is why I think choosing a knife purely by its steel specification can sometimes be misleading.
Two knives made from the same steel can still feel completely different.
Why?
Because we are not cutting food with steel specifications.
We are cutting with a three-dimensional object.
Blade thickness, edge angle, grind, taper, blade height and the geometry behind the edge all influence how easily a knife passes through food.
A very sharp edge can enter an ingredient easily, but if the blade geometry creates resistance behind that edge, the entire cutting motion may still feel heavy.
This is one reason a Gyuto, Santoku and Sujihiki can produce very different sensations even when all three are extremely sharp.
A Sujihiki moving through sashimi has a different purpose from a Santoku working through vegetables.
Balance does not create sharpness by itself, but it can strongly influence how that sharpness feels in your hand.
7. The Best Japanese Knife Sharpness Cannot Be Explained by Numbers Alone
After more than 25 years working with kitchen knives, perhaps the most interesting thing I have learned is how difficult it is to describe the perfect edge.
HRC cannot explain everything.
Steel cannot explain everything.
Sharpening angle cannot explain everything.
Even a paper-cutting test cannot explain everything.
There is a moment when a properly sharpened knife touches an ingredient and simply goes through.
No hesitation.
No unnecessary pressure.
No feeling that you need to force the blade.
You feel it immediately.
That sensation is what I think about when I hear the word Kireaji.
And perhaps this is also why Japanese knives remain so interesting to me after decades in professional kitchens.
I still do not produce exactly the same edge every single time I sharpen.
Sometimes I finish sharpening and the knife feels good.
Sometimes it feels very good.
And occasionally, everything seems to come together perfectly and the blade simply glides.
Those moments remind me that sharpening is not just maintenance.
It is a skill that continues to teach you.
Japanese Knife Sharpness Is Something You Feel
We often try to understand Japanese knives through numbers.
HRC.
Blade length.
Sharpening angle.
Steel type.
These measurements are useful, but they cannot completely describe the experience of using a knife.
Japanese knife sharpness is ultimately something you feel through your hand and through the food you are cutting.
The steel matters.
The heat treatment matters.
The sharpening matters.
The geometry matters.
The person holding the knife matters too.
Perhaps that is the real meaning of Kireaji.
Not simply whether a knife is sharp, but how the knife feels when it cuts.
And even after more than 25 years of using knives professionally, that small difference still makes me want to pick up a knife, sharpen it again, and see if I can make the next edge just a little better.
When I imported my first batch of handmade Japanese knives, I ordered two or three of the same model. I expected them to look almost identical. After all, they had the same blade length, the same steel, the same handle material, and were made by the same craftsman.
But when I placed them side by side, I noticed something unexpected.
No two knives were exactly the same.
At first, I wondered if something was wrong. Then I realized I wasn’t looking at imperfections—I was looking at the beauty of true craftsmanship. That moment changed the way I saw handmade Japanese knives, and it reminded me why so many people around the world value them so highly.
Handmade Japanese Knives Reflect the Hands That Made Them
One of the biggest differences between handmade Japanese knives and factory-produced knives is that every step involves skilled human hands.
Even when a blacksmith follows the same design repeatedly, every hammer strike is unique. Every blade is shaped, ground, and finished by hand. Small differences naturally appear throughout the process, and those differences become part of each knife’s character.
Rather than being flaws, they are evidence that a real craftsman created the knife instead of a machine.
Handmade Japanese Knives Have Unique Kurouchi and Hammered Finishes
If you compare two handmade Japanese knives with a Kurouchi or Tsuchime finish, you’ll quickly notice subtle differences.
The dark Kurouchi surface may have a slightly different texture.
The hammered pattern may catch the light differently.
Even the polish near the edge can vary from one knife to another.
These details cannot be copied perfectly because they are created by hand, making every knife feel genuinely individual.
➡ Internal Link: Why I Still Use Carbon Steel for Sashimi After 25 Years
Every Wooden Handle Is Naturally Different
The blade isn’t the only part that tells a story.
Natural wood has its own grain, color, and texture. Even if two handles are made from the same species of wood, they will never look completely identical.
Some pieces have darker lines.
Others have lighter tones.
Some display dramatic grain patterns, while others appear clean and understated.
These natural variations make every handmade Japanese knife even more personal.
Small Differences Are Part of Traditional Craftsmanship
Traditional Japanese workshops aim for exceptional quality.
That difference is important.
A craftsman focuses on creating the best possible knife rather than producing thousands of completely identical pieces. Slight variations in finish or appearance are simply part of the handmade process that has been passed down through generations.
This is one reason collectors, chefs, and cooking enthusiasts often appreciate handmade Japanese knives so much.
➡ Internal Link: Samurai Century | The Finest Expression of Tosa Knife Craftsmanship, Passed Down Since the Age of the Chōsokabe Clan
Many people assume that two knives with the same specifications should look exactly alike.
That’s true for mass-produced products.
It isn’t true for handmade Japanese knives.
The subtle differences in finish, texture, wood grain, and overall appearance aren’t defects—they’re signs that the knife was made through traditional craftsmanship rather than automated production.
Once I understood that, I stopped searching for perfect uniformity and started appreciating individuality instead.
That’s one of the reasons handmade Japanese knives continue to impress me every time I open a new shipment.
If you’re looking for a premium Japanese kitchen knife that combines exceptional sharpness with easy maintenance, the 180mm SG2 Santoku deserves serious attention.
Among modern stainless steels, SG2 has earned a reputation as one of the finest choices available. It offers remarkable edge retention, excellent corrosion resistance and refined cutting performance, making it a favourite among professional chefs and passionate home cooks alike.
But no knife steel is perfect.
The 180mm SG2 Santoku also has a few disadvantages that every buyer should understand before making an investment. In this article, I’ll explain both the strengths and weaknesses honestly, based on my experience as a chef, so you can decide whether this knife is right for you.
The 180mm SG2 Santoku combines premium powder metallurgy stainless steel with one of Japan’s most versatile knife shapes. At 180mm, it’s large enough for meat, fish and vegetables, yet compact enough to feel comfortable for everyday cooking.
Its rosewood octagonal handle adds traditional Japanese character while providing a secure and balanced grip.
One of the biggest advantages of the 180mm SG2 Santoku is its outstanding edge retention. SG2’s powder steel structure allows the blade to stay sharp much longer than many conventional stainless steels, reducing how often you need to sharpen it.
Excellent Corrosion Resistance
Unlike traditional carbon steels, SG2 offers excellent resistance to rust. You should still wash and dry the knife after use, but maintenance is far easier than with reactive carbon steel, making it an excellent choice for cooks who want premium performance without constant care.
Beautiful Balance Between Tradition and Technology
The combination of advanced SG2 steel and a handcrafted rosewood octagonal handle creates a knife that feels modern while preserving the beauty of traditional Japanese craftsmanship.
The same hardness that allows SG2 to keep its edge also makes it slower to sharpen. Beginners may need more patience and a quality whetstone to restore the edge properly.
Premium Price
SG2 is considered one of the highest-grade stainless knife steels available, so it naturally costs more than many VG10 or Ginsan knives. While the performance often justifies the investment, it may not be necessary for every cook.
Requires Proper Technique
The 180mm SG2 Santoku is a precision cutting tool, not a heavy-duty cleaver. Avoid cutting frozen food, bones or twisting the blade during use, as the thin edge can chip if misused.
If you value long-lasting sharpness, premium stainless steel and traditional Japanese craftsmanship, the 180mm SG2 Santoku is one of the finest choices available.
It isn’t the cheapest knife, nor is it the easiest steel to sharpen. However, those trade-offs are exactly what allow SG2 to deliver such impressive cutting performance.
For cooks who appreciate quality over compromise, this knife represents an outstanding balance of beauty, durability and precision.
When people think of beautiful Japanese knives, they often picture polished Damascus blades or traditional wooden handles. While those features certainly have their charm, sometimes it is the combination of colours that leaves the strongest impression.
That is exactly what makes these Black and Red Japanese Knives so memorable.
The deep black and vibrant red octagonal handles create a striking contrast that reflects both elegance and strength. Inspired by traditional Japanese aesthetics, these handcrafted knives are designed not only to perform exceptionally in the kitchen but also to become pieces you are proud to display.
Whether you’re a professional chef or a passionate home cook, these knives offer something special every time you pick them up.
If you’re looking for authentic handcrafted Japanese knives in Australia, you’ll find our carefully selected collection at Asaoya Yaichi
Japanese craftsmanship has always balanced beauty with practicality.
Black has long represented sophistication, stability and quiet confidence, while red symbolises passion, celebration and energy. Together they create a timeless contrast that immediately attracts attention without appearing overly flashy.
These Black and Red Japanese Knives perfectly capture that balance.
Each knife features a beautiful Damascus blade paired with a carefully finished octagonal handle combining rich black and vibrant red. The result is a knife that looks equally at home in a professional sushi bar, an open restaurant kitchen or a modern family home.
Unlike mass-produced knives, handcrafted Japanese knives develop a personal connection with their owner. Every scratch tells a story, and every meal prepared becomes part of that journey.
Although these knives share the same elegant design language, each serves a different purpose in the kitchen.
165mm Usuba A8 Hammered Damascus
The 165mm Usuba is designed primarily for vegetables.
Made from A8 stainless steel, it offers excellent corrosion resistance, toughness and easy maintenance. The hammered Damascus finish not only adds visual depth but also helps reduce food sticking to the blade.
Whether you’re preparing fine julienne vegetables, decorative garnishes or paper-thin slices, the Usuba provides impressive precision while remaining forgiving for everyday use.
Its lightweight balance also makes long preparation sessions far more comfortable.
165mm Santoku A10 Damascus
The matching 165mm Santoku features A10 stainless steel.
With its higher carbon content, A10 achieves greater hardness and longer edge retention than A8 while still offering excellent corrosion resistance.
As an all-purpose Japanese kitchen knife, the Santoku handles vegetables, meat and fish with remarkable ease.
For many home cooks, this will quickly become the knife they reach for every day.
Beautiful knives should never be reserved only for special occasions.
These Black and Red Japanese Knives were made to be used.
Every blade is handcrafted using techniques that have been refined over generations while incorporating modern stainless steel for practical everyday performance.
The octagonal handles provide a comfortable grip for both left- and right-handed users, while the Damascus pattern ensures every knife has its own unique appearance.
They’re not simply decorative pieces.
They’re tools designed to prepare countless family meals, dinner parties and special celebrations for many years.
As someone who has worked as a professional chef for over 25 years, I’ve learned that the best knife is the one you genuinely enjoy using.
Performance is essential.
Comfort matters.
But so does the feeling you get every time you reach for it.
That’s one reason I appreciate matching knife collections.
When your knives share the same design language, your kitchen feels organised, professional and enjoyable to work in.
These Black and Red Japanese Knives deliver exactly that experience.
Final Thoughts on Black and Red Japanese Knives
Authentic Japanese knives are an investment that can be enjoyed for many years.
These two handcrafted knives combine traditional Japanese beauty with practical everyday performance.
Purchased individually, each knife offers outstanding quality.
Purchased together, they create a striking Japanese knife set whose black and red contrast makes an unforgettable impression.
Whether you’re upgrading your own kitchen or searching for a meaningful gift, this matching pair offers beauty, craftsmanship and functionality in equal measure.
If you’d like to explore these knives in more detail or discover more handcrafted Japanese knives from Tosa, visit https://asaoyayaichi.com.au.
Every knife in our collection has been carefully selected because we believe exceptional craftsmanship deserves to be used, appreciated and passed on.
The 165mm Kiritsuke Thick Deba Aogami #2 Kurouchi Walnut Octagonal Handle belongs firmly in the second category.
At first glance, its black Kurouchi finish may seem simple compared to polished Damascus blades. But beneath that traditional appearance lies one of the finest examples of Tosa craftsmanship, a style of knife making that has been refined for more than 400 years.
When many people hear the word Deba, they imagine a heavy, single-bevel knife used only by professional Japanese chefs.
A Kiritsuke Thick Deba from Tosa is different.
This knife combines the strength of a traditional thick deba with the practicality of a double-bevel edge, making it far easier for both professional chefs and passionate home cooks to use.
Whether you’re breaking down a whole fish, trimming large cuts of meat, or tackling tougher ingredients, the extra blade thickness provides confidence and durability that lighter knives simply cannot match.
For Australian cooks who enjoy preparing salmon, kingfish, tuna, snapper, grouper, or other large reef fish, this style of knife offers versatility that surprises many people.
The 165mm Kiritsuke Thick Deba is the size I recommend for most people.
It offers plenty of power for breaking down larger fish such as salmon and kingfish, while still being comfortable enough for everyday use.
For those who regularly prepare slightly smaller fish, there’s also a 150mm Kiritsuke Thick Deba Aogami #2 Kurouchi with a Walnut Octagonal Handle available.
The shorter blade feels a little more agile when working with fish like snapper, grouper, and other medium-sized species where a more compact knife offers greater control.
To be honest, I don’t think most people need to own both sizes.
For the vast majority of cooks, the 165mm is the more versatile option.
The 150mm simply provides another excellent choice if you mainly prepare smaller fish and prefer a slightly more compact knife.
The Kurouchi finish is created by leaving part of the protective scale formed during forging on the blade. Rather than polishing everything away, Tosa blacksmiths preserve part of the knife’s history.
The result is a knife that feels honest.
Nothing unnecessary.
Nothing decorative for decoration’s sake.
Just practical craftsmanship built for daily work.
Over time, the Kurouchi finish develops its own character, making every knife unique to its owner.
Knife making in Tosa traces its roots back more than four centuries to the era of the Chōsokabe Clan
Originally producing tools for forestry, farming, and daily life, Tosa’s blacksmiths built a reputation for practical, dependable blades that could withstand demanding work.
That philosophy remains unchanged today.
This knife isn’t trying to be flashy.
It’s trying to perform.
Every hammer strike, every grind, and every final sharpening reflects a tradition passed down through generations of craftsmen who value function above fashion.
When you hold this knife, you’re holding far more than steel.
You’re holding over 400 years of Tosa craftsmanship.
At Asaoya Yaichi , our goal is to introduce authentic handcrafted Tosa knives to Australia while supporting the skilled craftsmen who continue this remarkable tradition.
Every knife is carefully selected because I genuinely believe in its quality—not because it follows a trend, but because it represents the craftsmanship, reliability, and history that have defined Tosa knife making for generations.
If you’re looking for a knife with genuine history, outstanding performance, and timeless craftsmanship, I invite you to explore our collection of handcrafted Tosa knives.
This 180mm Santoku Aogami #2 Green Micarta Handle with Turquoise Spacer is one of those rare knives that feels like it belongs to both the past and the present.
When people think about Japanese knives, they often focus on razor-sharp edges, beautiful finishes, or premium steels. Those qualities certainly matter, but I believe the most valuable part of a handcrafted knife is something you cannot immediately see.
It is the history.
It is the knowledge passed from one craftsman to another.
It is the spirit that has survived for centuries.
That is exactly what I see every time I hold this Santoku.
The story of Tosa knives begins more than 400 years ago, during Japan’s Sengoku period.
According to the history shared by Ishizuchi Kanamono Manufacturing, the roots of Tosa blacksmithing can be traced back to the rule of the Chōsokabe Clan, who unified Tosa Province in the late 1500s. Historical records mention that nearly 400 blacksmiths were already working throughout the region.
As Tosa became one of Japan’s leading forestry areas, local craftsmen produced axes, hatchets, sickles, and countless agricultural tools needed for everyday life.
The techniques required to create tools that could survive years of demanding work eventually evolved into the craftsmanship used to forge kitchen knives.
Those same forging methods, refined over hundreds of years, are still alive today.
Every handcrafted Tosa knife represents generations of practical knowledge rather than simply modern manufacturing.
That heritage is one of the reasons I became fascinated by Tosa knives.
This Santoku stays true to those traditional roots.
Its core steel is Aogami #2 (Blue Steel No.2), one of Japan’s most respected carbon steels.
Professional chefs have trusted Aogami steels for decades because they offer outstanding sharpness, excellent edge retention, impressive toughness, and are surprisingly enjoyable to sharpen.
Rather than feeling disposable, Aogami #2 develops character over time.
With proper care, the edge becomes familiar.
The sharpening becomes rewarding.
The knife slowly becomes your own.
That is something mass-produced knives rarely offer.
One reason I started Asaoya Yaichi was because I wanted people outside Japan to experience authentic craftsmanship rather than simply buying another factory-made knife.
Many knives today are designed around efficiency.
Tosa knives are different.
They are built around craftsmanship.
Every hammer mark.
Every grind.
Every sharpened edge.
Every handle fitting.
They all reflect the experience of skilled craftsmen who continue techniques handed down over generations.
That is becoming increasingly rare.
When you purchase a handcrafted Tosa knife, you are supporting more than a product.
You are helping preserve one of Japan’s traditional crafts.
You are supporting craftsmen whose knowledge has survived since the age of the samurai.
Whenever I hold this Santoku, I cannot help but think about the generations of blacksmiths who came before.
From agricultural tools forged during the time of the Chōsokabe Clan…
To the exceptional kitchen knives produced today…
The philosophy has remained remarkably consistent.
Build tools that work.
Build tools that last.
Build tools that people will be proud to use every day.
That is exactly what this knife represents.
The 180mm Santoku Aogami #2 Green Micarta Handle with Turquoise Spacer is not simply a beautiful Japanese knife.
It is the meeting point of over four centuries of Tosa blacksmithing, premium Aogami #2 steel, modern craftsmanship, and the quiet beauty of wabi-sabi.
After more than twenty-five years as a chef, I can honestly say that knives like this do not appear very often.
If you are searching for an authentic handcrafted Japanese knife that carries genuine history, exceptional cutting performance, and timeless design, I believe this Santoku is one of the finest examples of Tosa craftsmanship available today.
It is more than a knife.
It is a small piece of Japanese history that can be used, appreciated, and passed down for generations.
Discover Authentic Tosa Knives
If this knife speaks to you, I’d love for you to explore the rest of our collection.
Every knife at Asaoya Yaichi is personally selected based on more than 25 years of professional chef experience, with a focus on craftsmanship, performance, and the traditions of Tosa blacksmithing.
When people search for Japanese knives, they often picture striking Damascus patterns, polished finishes, or eye-catching designs.
Those features certainly have their place.
But after spending more than 25 years working as a chef, I’ve come to believe that the best knife isn’t necessarily the one that attracts the most attention.
It’s the one you enjoy reaching for every single day.
A knife that feels perfectly balanced in your hand.
A knife that performs beautifully, looks elegant without being flashy, and quietly earns your trust over time.
That is the philosophy behind this collection.
In Japan, there is a word that perfectly expresses this way of thinking.
But its true meaning goes much deeper than manufacturing.
It represents the dedication of Japanese craftspeople who constantly refine their skills, pay attention to the smallest details, and never compromise on quality.
For generations, Japanese blacksmiths have passed their knowledge from one craftsman to the next.
Every knife they create reflects years of experience, patience, and pride in their work.
Rather than chasing trends, they focus on creating tools that perform beautifully and last for many years.
That philosophy is exactly what inspired this collection.
Every knife is designed to honour traditional Japanese craftsmanship while fitting naturally into today’s kitchens.
Premium VG10 Steel with a Beautiful 67-Layer Damascus Blade
Every knife in this collection is handcrafted in Japan using VG10 stainless steel and features a beautifully finished 67-layer Damascus blade.
VG10 has earned its reputation as one of Japan’s most respected stainless steels for good reason.
It offers outstanding sharpness, excellent edge retention, impressive corrosion resistance, and is much easier to maintain than traditional carbon steel.
That makes it an excellent choice for both professional chefs and passionate home cooks who want the performance of premium Japanese knives without constantly worrying about rust.
The Damascus blade isn’t simply there to create a beautiful pattern.
Each layer reflects the precision and care of Japanese craftsmanship.
The flowing lines give every knife its own unique character while maintaining the practical performance needed for everyday cooking.
Beautiful tools shouldn’t stay in a display cabinet.
They should become part of your daily routine.
If you’d like to learn more about choosing the right steel, you may also enjoy this article:
While the blade immediately catches your attention, what truly makes this collection different is the handle.
Traditional Japanese knives are often fitted with magnolia or walnut handles.
They’re beautiful and timeless.
This collection takes a different approach.
The calm green handle introduces a contemporary style while still respecting the understated beauty that Japanese craftsmanship is known for.
Rather than competing with the Damascus pattern, it complements it.
Nothing feels over-designed.
Nothing feels excessive.
The balance between blade and handle creates a knife that feels refined, comfortable, and natural in the hand.
It’s modern without losing its connection to tradition.
To me, that’s one of the most attractive features of this collection.
Another Expression of Japanese Beauty
Wabi-Sabi
Some time ago, I introduced our Wabi-Sabi collection.
That series celebrated traditional finishes, natural textures, and the quiet beauty that develops through years of use.
This collection tells a different story.
Instead of focusing entirely on traditional appearance, it combines centuries of Japanese blacksmithing with contemporary materials and thoughtful design.
It’s a different expression of Japanese craftsmanship.
Neither is better.
They’re simply different philosophies.
If you’re interested in the traditional side of Japanese knife making, you might also enjoy reading:
This collection is available in three carefully selected models.
Santoku
The Santoku is one of Japan’s most versatile kitchen knives.
Whether you’re preparing vegetables, slicing meat, or cutting fish, it’s designed to handle everyday cooking with ease.
Its balanced size makes it an excellent choice for home cooks looking for a single knife that can do almost everything.
Gyuto
The Gyuto is Japan’s answer to the Western chef’s knife.
Its longer blade offers greater versatility when working with larger vegetables, meat, and fish while maintaining the precision that Japanese knives are known for.
If you enjoy preparing a wide variety of ingredients, the Gyuto quickly becomes one of the most useful knives in the kitchen.
Petty
The Petty knife is designed for precision.
From peeling fruit and vegetables to trimming meat or preparing garnishes, it provides complete control for delicate work that larger knives simply can’t match.
Although it’s the smallest knife in the collection, many chefs consider it one of the most frequently used.
Each knife has its own purpose.
Together, they create a collection capable of handling almost every task in the kitchen.
Because every knife shares the same premium VG10 steel, beautifully finished 67-layer Damascus blade, and distinctive green handle, they work together not only in performance but also in appearance.
Why I Recommend Building the Complete Collection
Many people begin by purchasing a single Japanese knife.
That’s exactly what I would recommend if you’re just starting your journey.
However, once you experience the quality of a handcrafted knife, it’s easy to understand why so many people gradually build a complete collection.
Having the right knife for each task makes cooking smoother, more enjoyable, and more efficient.
The Santoku becomes your everyday companion.
The Gyuto handles larger ingredients with confidence.
The Petty takes care of all the finer details.
Instead of asking one knife to do every job, each knife performs the task it was designed for.
As a result, not only does cooking become easier, but your knives also stay in better condition because each blade is used appropriately.
My Experience After More Than 25 Years as a Chef
Having worked as a chef for more than 25 years, I’ve noticed something that many people don’t think about until they experience it themselves.
When your knives all belong to the same collection, people notice.
In professional kitchens, fellow chefs often comment on how clean and professional a matching set looks.
It’s not unusual for someone to walk past and say,
“Those knives look great together.”
I’ve also spent many years working at sushi counters where customers can clearly see the knives being used.
Interestingly, customers notice them too.
I’ve had guests compliment the appearance of a matching set before they’ve even tasted the food.
Of course, beautiful knives don’t make someone a better chef.
Skill, experience, and technique will always be far more important.
But presentation matters.
Just as chefs take pride in wearing a clean uniform and maintaining an organised workstation, using knives from the same collection creates a sense of consistency and professionalism.
It reflects the respect we have for our craft.
That’s one of the reasons I personally enjoy using knives from the same series whenever possible.
Not because they match.
But because together they create a workspace that feels organised, intentional, and enjoyable to work in every day.
For me, that’s another reason why I often recommend building a complete Japanese knife set rather than collecting individual knives from different collections.
It’s something I’ve genuinely appreciated throughout my career, and I believe many passionate home cooks will appreciate it too.
More Than Just a Knife
A yanagiba knife that has been used for 40 years
After more than 25 years as a chef, I’ve come to realise that a great knife is far more than just a cutting tool.
It’s something you rely on every day.
It becomes part of the way you cook, the way you work, and even the way you present yourself as a chef.
The longer you use a well-made knife, the more you appreciate the skill, experience, and dedication that went into creating it.
That’s exactly what Monozukuri is all about.
It’s not simply making products.
It’s about creating something with care, purpose, and pride—something designed to be used and appreciated for many years.
Every handcrafted knife in this collection reflects that philosophy.
At Asaoya Yaichi, our goal has never been to offer the largest selection of Japanese knives.
Instead, we carefully select knives that we genuinely believe in.
As someone who has spent over two decades working in professional kitchens, I understand how important it is to trust the tools you use every day.
That’s why every knife we offer is chosen not only for its appearance, but also for its performance, durability, and the craftsmanship behind it.
We want to introduce authentic handcrafted Japanese knives that you’ll enjoy using for many years—not simply because they’re beautiful, but because they earn their place in your kitchen every time you cook.
Continue Exploring Japanese Knives
If you’d like to learn more about authentic Japanese knives, you may also enjoy these articles:
If you’re looking for handcrafted VG10 Damascus Japanese knives that combine traditional Japanese craftsmanship with thoughtful modern design, we invite you to explore this collection.
Whether you choose the Santoku, Gyuto, Petty, or the complete Japanese knife set, you’ll be investing in knives that were created to perform beautifully for years to come.
More importantly, you’ll experience a small part of the philosophy that has guided Japanese craftspeople for generations.
As both a chef and the founder of Asaoya Yaichi, I hope these knives bring you the same enjoyment and confidence they’ve brought me throughout my career.
When most people think of Japanese knives, they imagine beautiful handcrafted blades made from carbon steel.
There’s no doubt carbon steel has its own charm. But for many people, one question always comes first.
“Will it rust if I don’t take perfect care of it?”
If you love the traditional appearance of Japanese knives but want something that’s easier to use every day, there’s one combination that deserves far more attention.
Ginsan stainless steel with a traditional Nashiji finish.
Ginsan, also known as Silver #3 steel, is one of Japan’s finest stainless steels. It offers excellent corrosion resistance, making it much easier to maintain than traditional carbon steel while still delivering the razor-sharp edge and smooth cutting performance that Japanese knives are famous for.
For many home cooks in Australia, this means enjoying authentic Japanese craftsmanship without constantly worrying about rust or complicated maintenance.
Another feature that makes these knives so appealing is the Nashiji finish.
“Nashiji” literally means “pear skin” in Japanese, referring to the subtle textured finish on the blade. Rather than a mirror polish or an eye-catching Damascus pattern, Nashiji has a quiet, understated beauty that reflects traditional Japanese craftsmanship. It isn’t flashy, but that’s exactly why so many knife enthusiasts appreciate it. The finish also helps hide the small scratches that naturally appear during everyday cooking, making it as practical as it is beautiful.
Another traditional feature of this series is its octagonal magnolia wood handle with a genuine buffalo horn ferrule. The lightweight magnolia wood offers excellent balance and comfort during extended use, while the natural buffalo horn ferrule has long been used on traditional Japanese knives. Because buffalo horn is a natural material, every handle has its own unique colour and pattern, making each knife one of a kind.
This handcrafted Tosa Japanese knife series is available in four of the most useful styles: the versatile Santoku, the all-purpose Gyuto, the vegetable-focused Nakiri, and the compact Petty knife.
Each knife offers the same balance of traditional Japanese aesthetics, outstanding cutting performance, and the everyday convenience of premium stainless steel.
Because the series includes all four styles, many people choose to build a matching Japanese knife set. Having the same Nashiji finish across your collection creates a clean, elegant, and professional look in your kitchen while giving you the right knife for every cooking task. Whether displayed on a magnetic knife holder or stored together, the matching finish brings a timeless sense of style that many chefs and home cooks appreciate.
For anyone searching for authentic Japanese knives in Australia, Ginsan Nashiji Tosa knives offer exceptional value. They combine the traditional appearance and craftsmanship of handcrafted Japanese knives with the practicality of stainless steel, making them an excellent choice for both first-time buyers and experienced cooks.
At Asaoya Yaichi, we carefully select handcrafted Japanese knives made by skilled craftspeople in Tosa, Japan. Every knife is designed to be used, appreciated, and enjoyed for many years.
Whether you’re looking for a single knife or want to build a complete Japanese knife set, our Ginsan Nashiji collection includes Gyuto, Santoku, Nakiri, and Petty knives to suit every style of cooking.
Explore our handcrafted Japanese knives and discover the Ginsan Nashiji collection at:
Find the knife that suits your cooking style and experience the perfect balance of traditional Japanese craftsmanship, premium stainless steel performance, and timeless design.
When people think of a beautiful Japanese knife, many imagine a mirror-polished blade or an eye-catching Damascus pattern.
While those styles certainly have their place, Japanese culture has long embraced a different idea of beauty.
Rather than seeking perfection, traditional Japanese aesthetics celebrate simplicity, balance, authenticity, and the quiet character that develops over time.
This philosophy is known as Wabi-Sabi.
Wabi-Sabi isn’t simply about appearance. It is about appreciating craftsmanship, natural materials, and the beauty that comes from using something every day.
This series is also available in four different handle colours — Red, Yellow, Orange, and Blue.
Each colour offers its own distinctive personality while maintaining the same exceptional craftsmanship and cutting performance.
Whether you prefer something bold or something more understated, there is a version that will suit your own style and kitchen.
There is also something very special about this collection that I’d like to share.
I was recently told that, due to personal circumstances, the blacksmith responsible for producing these knives may not be creating new designs in the future.
Nothing has been officially confirmed, and of course everyone hopes that new creations will continue.
However, there is a genuine possibility that this collection could become one of the final series produced by this craftsman.
If that turns out to be the case, these knives will represent far more than beautiful kitchen tools.
They will become lasting examples of one artisan’s work and dedication.
To me, that adds another layer of meaning to owning one.
Not because it might become rare, but because it carries the story of a craftsman whose work deserves to be appreciated.
Of course, beauty alone isn’t enough.
A great knife must also perform exceptionally well.
This Santoku is forged from VG10N stainless steel, one of Japan’s most respected stainless steels.
It offers excellent edge retention, impressive corrosion resistance, and straightforward maintenance, making it an excellent choice for both professional chefs and passionate home cooks.
If you’ve always admired handcrafted Japanese knives but felt hesitant about maintaining carbon steel, VG10N offers an ideal balance between performance and convenience.
The 180mm Santoku is also one of the most versatile knives you can own.
From vegetables and meat to fish and everyday meal preparation, it handles almost every kitchen task with confidence.
It is no surprise that Santoku has become one of the world’s most popular Japanese knife styles.
Having worked as a chef for more than 25 years, I’ve handled countless Japanese knives.
Some impress immediately with extravagant finishes.
Others focus purely on performance.
But the knives that remain with you for years are usually the ones you naturally reach for every single day.
This Santoku feels exactly like that.
Beautiful without trying too hard.
Elegant without being fragile.
Practical enough for everyday cooking while carrying the soul of traditional Japanese craftsmanship.
Perhaps that is the true meaning of Wabi-Sabi.
Finding beauty not in perfection, but in honest craftsmanship, thoughtful design, and an object that becomes more meaningful every time you use it.
If you’re looking for a handcrafted Japanese knife that combines timeless beauty, exceptional performance, and the possibility of becoming part of a very special chapter in a Japanese craftsman’s story, this Santoku deserves a place in your kitchen.
Many handcrafted Japanese knives are made from high-carbon steel, such as Aogami (Blue Steel) or Shirogami (White Steel).
These steels are loved by professional chefs because they offer exceptional sharpness, excellent edge retention, and are easier to sharpen than many stainless steels.
The trade-off is that carbon steel reacts more easily with moisture and acidic foods, so it can develop rust if left wet.
My Own Experience
I learned this the hard way.
Even after rinsing my knife with water, I once left it sitting for a while after cutting citrus fruit.
When I came back, small spots of rust had already started to appear.
It wasn’t because the knife was poorly made.
It was because the acid from the citrus remained on the blade long enough to react with the carbon steel.
Since then, I’ve made it a habit to wash my knives, dry them immediately, and never leave them sitting wet.
If storing the knife for an extended period, apply a thin coat of camellia oil (tsubaki oil), which has traditionally been used in Japan to protect carbon steel from rust. If you don’t have camellia oil, a small amount of food-grade cooking oil can also be used as a temporary alternative.
What If Rust Already Appears?
Don’t panic if you notice rust on your knife.
In many cases, light surface rust can be removed before it causes any serious damage.
Depending on the severity of the rust, you may be able to remove it by:
Sharpening the blade on a whetstone.
Gently polishing the affected area with fine-grit sandpaper.
Using a rust eraser designed for knives and tools, such as products commonly known in Japan as Sabitoru.
The most important thing is to deal with rust as soon as you notice it. The longer rust remains on the blade, the more difficult it can become to remove.
One of the best ways to keep a carbon steel knife in excellent condition is to prevent rust from forming in the first place.
Once rust starts to develop, the affected areas can become more susceptible to rusting again if they are not properly cleaned and protected.
That’s why it’s best to care for your knife from the day you buy it. Keeping the blade clean and dry from the beginning is the easiest way to maintain both its appearance and its cutting performance for years to come.
As with most knife care, prevention is always easier than restoration.
Carbon steel knives aren’t difficult to own—they’re simply different.
Once you understand how to care for them, you’ll see why so many professional chefs continue to choose carbon steel over stainless steel.
However, if you’re not confident that you’ll be able to give a carbon steel knife the care it needs, there’s nothing wrong with choosing a stainless steel knife instead.
A knife that suits your lifestyle is always a better choice than one that causes unnecessary stress.
At Asaoya Yaichi, we proudly offer authentic handcrafted Tosa knives made by skilled Japanese craftspeople, including both carbon steel and stainless steel options.
If you’re looking for an authentic Japanese knife, we’d be happy to help you find the one that’s right for you.
Black-Finished Knives changed the way I think about Japanese knives. I used to believe they looked cheap, but after years of using them professionally, my opinion completely changed.
When people think of a beautiful Japanese knife, many imagine a polished Damascus blade with striking patterns.
I understand why.
I actually use several Damascus knives myself. To be honest, many of them came to me as sample knives rather than because I specifically chose Damascus.
But if I’m being completely honest, I’ve never believed a knife is beautiful simply because it has a Damascus pattern.
A great-looking knife is a great-looking knife, whether it’s Damascus, polished, or black-finished.
If you’re searching for a handcrafted Japanese knife made by skilled artisans—not just one that looks beautiful, but one that’s built to perform for years—I’d love to introduce you to the craftsmanship of Tosa.
One of the biggest lessons I’ve learned as a chef is that a knife should never be judged by its appearance alone. When I was younger, I believed a polished blade represented quality, while a black-finished knife looked unfinished or even cheap. Years of working in professional kitchens completely changed that way of thinking.
A knife earns its value through performance. The way it holds its edge, the confidence it gives you during service, and how it continues to perform after years of use are far more important than a shiny finish. That’s exactly why my opinion of Kurouchi knives changed so dramatically.
At Asaoya Yaichi, we carefully select authentic handcrafted Tosa knives made by experienced Japanese blacksmiths. Every knife is forged using traditional techniques that have been refined over generations, with an emphasis on performance, durability, and practical everyday use.
Whether you choose a polished finish, Damascus, or a traditional Kurouchi finish, there is no single “best” choice. Every finish has its own character and purpose. The most important thing is finding a knife that suits your cooking style, feels comfortable in your hand, and becomes a trusted tool you’ll enjoy using for many years.
If you’ve never used a black-finished knife before, don’t let your first impression stop you. I made exactly the same mistake. Sometimes the knives that impress you the most aren’t the ones that shine the brightest—they’re the ones that quietly earn your trust every single day.
Explore our collection and discover the handcrafted Tosa knife that could become part of your own story.
If you really prefer this method, a better option would be to buy a smooth concrete paver or a flat tile and use that instead.
Just make sure it’s genuinely flat. If the surface isn’t flat, your whetstone won’t be either. Also, some tiles are so smooth that they don’t remove material very effectively.
For consistent results, a proper flattening stone is still the easiest and most reliable solution.
When a knife does not become as sharp as expected, many people assume the problem is their technique or the knife itself.
But sometimes, the real problem is the whetstone.
As a whetstone is used, its surface gradually wears down. Because we often sharpen in the same area, the centre can become hollow. Flattening restores the stone to an even surface so the blade can make consistent contact while sharpening.
What Happens When the Stone Is Not Flat?
Sharpening on a hollow whetstone can make it difficult to maintain a consistent angle.
The blade may still become sharp enough to cut, but the bevel can become uneven. It may also be difficult to raise an even burr along the entire edge, and over time the shape of the blade may be affected.
This is something I learned through experience.
A Lesson From My Early Years as a Chef
When I first became a chef, I used a whetstone that was kept at the restaurant.
It had not been flattened and was already noticeably hollow. At the time, I did not understand why that mattered.
My knives became sharp enough to use, so I continued sharpening on that same stone for around two years.
Later, while visiting Japan, I took one of my knives back to the shop where I had bought it in Kappabashi and asked them to sharpen it.
The person looked at the knife and said:
“This is no good.”
He laughed dismissively, but did not explain what was wrong, why it had happened, or how I could correct it.
I will not name the shop. However, I never bought another knife from them.
I accept that my sharpening was not good. But beginners cannot improve when they are only criticised and given no explanation.
How Often Should You Flatten a Whetstone?
There is no single rule.
It depends on how often you sharpen, the hardness of the stone and the amount of pressure you use.
Some people flatten their stone before every sharpening session. Others check it after sharpening several knives.
The important thing is to inspect the surface regularly and flatten it before the hollow becomes too deep.
At the moment, Asaoya Yaichi does not offer a professional sharpening service, and I do not pretend to be a sharpening specialist.
However, I do want to treat customers differently from the way I was treated.
People should not be made to feel embarrassed because they are beginners or because they have made a mistake. I made plenty of mistakes myself, including sharpening on an unflattened whetstone for two years.
When possible, I want to explain:
What has gone wrong
Why it matters
What can be done next
Selling a knife should not be the end of the relationship.
Good information and simple maintenance can help a well-made knife remain part of someone’s kitchen for many years.
At Asaoya Yaichi, we offer handcrafted Tosa knives made by skilled Japanese craftspeople.
Whether you are buying your first Japanese knife or adding to your collection, proper sharpening and whetstone maintenance will help it perform at its best.
Explore our collection of authentic handcrafted Tosa knives.
One small detail that many people overlook is the buffalo horn ferrule (the black section between the blade and the wooden handle).
Besides giving the knife a traditional Japanese appearance, it is durable and easy to maintain.
The only trade-off is that it adds a little extra weight compared to an all-wood handle.
Personally, I still prefer lighter wooden handles, but I can certainly understand why many people appreciate the buffalo horn option for its durability and premium look.
There really isn’t a right or wrong choice—it simply depends on what feels best in your hand.
During my visit, I also learned that special handle materials are available through custom orders.
So if you’re looking for something truly personal or distinctive, there may be more options beyond the standard lineup.
Custom handles can make a handcrafted Japanese knife even more unique, creating a knife that reflects your own style as well as the craftsmanship behind it.
My Advice After 25 Years as a Chef
If you’re buying your first Japanese knife, don’t choose based only on the steel.
Hold the knife if you can.
Pay attention to:
Weight
Balance
Shape
Handle material
A knife should feel like a natural extension of your hand.
Sometimes, changing the handle can make a bigger difference than changing the steel.
At Asaoya Yaichi, we work directly with Ishizuchi Kanamono Seisakusho to bring authentic handcrafted Tosa knives to Australia.
Whether you prefer a traditional magnolia handle, walnut, rosewood, or are interested in discussing a custom option, we’re happy to help you find a knife that suits both your cooking style and your hands.
Because the perfect Japanese knife isn’t only about how it cuts—it’s also about how it feels every time you pick it up.
Explore our collection at www.asaoyayaichi.com.au and discover handcrafted Japanese knives made to be used and appreciated for many years.
Japanese knives are often described as delicate or difficult to maintain.
From my experience, that’s not true.
After more than 25 years working as a chef in both Japan and Australia, I’ve found that most damage doesn’t happen while you’re cooking—it happens afterwards.
Rust, cracked handles, warped blades, and unnecessary repairs are often the result of a few simple habits that are easy to avoid.
Here are the five most common mistakes I’ve seen over the years, including a few I’ve learned from my own experience.
1. Leaving the Knife Wet After Use
If I had to choose the biggest cause of rust, this would be it.
After cooking, it’s easy to leave a knife on the cutting board or beside the sink while cleaning up.
Unfortunately, even a short period of moisture combined with food residue can start the rusting process.
Carbon steel is especially vulnerable, but stainless steel isn’t completely immune either.
A simple routine makes all the difference:
Wash the knife soon after use.
Dry it thoroughly.
Store it somewhere dry.
Those extra 30 seconds can add years to your knife’s life.
2. Only Rinsing the Knife After Cutting Citrus Fruits
Most people know that citrus fruits such as lemons and limes can affect a knife because of their acidity.
What I’ve personally experienced, however, is that simply rinsing the blade with water isn’t always enough.
I have rusted a knife myself after cutting citrus and only washing it with water.
Acid and juice can remain on the blade, especially near the edge, the heel, or where the blade meets the handle.
After cutting citrus, I always recommend:
Wash the knife properly with mild dishwashing liquid.
Rinse with clean water.
Dry it immediately and completely.
It’s a small habit that can prevent unnecessary rust.
3. Ignoring Small Rust Spots
Small rust spots are much easier to deal with than deep rust.
Once rust starts penetrating into the steel, removing it becomes much more difficult and time-consuming.
I’ve learned that preventing rust is always easier than restoring a damaged blade.
If you notice rust beginning to form, don’t leave it for another day.
Deal with it early.
Your knife will thank you for it.
4. Washing the Knife with Very Hot Water
Many people know not to use a dishwasher.
What isn’t discussed as often is washing a knife by hand with very hot water.
In my experience, repeatedly exposing a knife to very hot water can shorten its lifespan.
The blade can be placed under unnecessary stress from repeated temperature changes, while the wooden handle suffers even more.
Over time, excessive heat can cause the handle to:
Dry out
Expand and contract repeatedly
Develop small cracks
Split
Loosen around the tang
Eventually begin to rot from moisture entering through damaged areas
Once a wooden handle starts cracking, water and food residue can work their way inside, making it more difficult to keep clean and shortening the life of the handle.
Warm water is all you need.
Wash the knife quickly, dry both the blade and the handle immediately, and avoid soaking it.
5. Putting the Knife in the Dishwasher
This is probably the most well-known mistake, but it’s still worth mentioning.
Dishwashers expose knives to:
High temperatures
Strong detergents
Long periods of moisture
Contact with other utensils
These conditions can damage both the blade and the wooden handle.
Even if no damage is visible after one cycle, repeated dishwasher use can significantly shorten the knife’s lifespan.
A handcrafted Japanese knife deserves to be washed by hand.
Fortunately, that only takes a minute.
Japanese Knives Aren’t Difficult to Maintain
One of the biggest misconceptions is that Japanese knives require complicated maintenance.
In reality, they don’t.
Simply remember to:
Wash the knife soon after use.
Don’t leave it wet.
Properly wash it after cutting citrus fruits.
Remove rust before it becomes serious.
Avoid very hot water.
Never use a dishwasher.
Dry both the blade and the wooden handle thoroughly.
None of these steps are difficult.
They simply become good habits.
Final Thoughts
After more than 25 years in professional kitchens, I’ve learned that good knife care isn’t about doing something special.
It’s about avoiding a few simple mistakes.
The difference between a knife that lasts five years and one that lasts several decades often comes down to daily habits.
I still own a knife that has been in my family for over 40 years.
The reason it’s still in use today isn’t because it received special treatment.
It’s because someone took the time to wash it, dry it, and care for it properly after every use.
If you do the same, a quality Japanese knife can reward you with many years of reliable service.
People sometimes ask why I decided to start Asaoya Yaichi.
The answer is simple.
I wanted to introduce Australians to authentic handcrafted Tosa knives.
Not because they are fashionable.
Not because they are the most expensive.
But because I believe they deserve to be recognised for what they truly are.
For too long, I have seen mass-produced knives marketed as “Japanese knives” without representing the traditions that made Japanese craftsmanship respected around the world.
That isn’t what I wanted to share.
I wanted to introduce knives with a genuine story.
Knives made by skilled blacksmiths whose techniques have been handed down through generations.
Knives that improve with care instead of losing their value.
Knives that can still be used decades from now—just like the Yanagiba my mother used for around twenty years before passing it on to me, and that I’ve continued using for another twenty.
That knife reminds me that a truly great knife isn’t measured by how it looks on the first day.
It’s measured by how faithfully it serves over a lifetime.
More Than Selling Knives
Working with Ishizuchi Kanamono Seisakusho has strengthened that belief.
For more than a century, they have remained committed to supporting authentic craftsmanship and the people behind it.
That philosophy reflects exactly what I hope Asaoya Yaichi can become.
Not simply a shop.
But a bridge.
A bridge between the traditional blacksmiths of Tosa and the people who will use their work every day here in Australia.
Every knife carries the skill of the craftsman who forged it.
But its future belongs to the person who chooses to use it.
That relationship is what makes handcrafted knives so special.
A Final Thought
If there is one lesson I have learned after more than twenty-five years as a chef, it is this:
The best knife is not always the one that impresses you on the first day.
Sometimes, the best knife is the one that quietly earns your respect over many years.
That is exactly what happened to me.
I didn’t fall in love with Tosa knives the moment I first picked one up.
I fell in love with them after cooking with them.
After sharpening them.
After trusting them.
That journey changed the way I looked at knives forever.
It is also the reason Asaoya Yaichi exists today.
If you’ve always believed traditional Japanese knives are difficult to maintain, you may be surprised.
With a little knowledge and regular care, a handcrafted knife can stay with you for decades.
In future articles, I’ll be sharing practical knife care, sharpening techniques, and maintenance tips to help you get the very best from your knife—whether you’re a professional chef or cooking at home.
If this article encourages even one person to look beyond appearances and discover the craftsmanship, history and spirit behind a traditional Tosa knife, then I believe I have achieved something meaningful.
Because we are not simply preserving knives.
We are helping preserve the people, the skills and the traditions that continue to shape them.
Explore Authentic Tosa Knives
If this story resonates with you, I’d be honoured to welcome you to Asaoya Yaichi.
Every knife in our collection is carefully sourced through Ishizuchi Kanamono Seisakusho and handcrafted by traditional blacksmiths in Tosa, Japan.
