Choosing a knife can be overwhelming. With a variety of materials and design to choose from it can make the process confusing and challenging. However, we are here to help guide you through the process. It is important to remember that a good quality knife will be on the pricier end. However, in the long run, it will end up saving you money. This is because a "cheap" knife will break or dull faster, and you would have to constantly spend money purchasing a new knife every year or so. Once you have started using a quality knife, there is no going back.
We have broken down the characteristics into 5 components that you should be thinking about when choosing a knife.
#1: Steel Chemical Composition & Tempering
The steel is the soul of a knife. There are hundreds of different steels, each with their advantages and disadvantages, for you to choose from. However, when choosing the best steel, it is important to note that it is about choosing the best balance of physical properties that are important to you. The most important thing to remember is that a blade must be hard and flexible, tough and corrosion-resistant.
Hardness is a key characteristic that indicates how sharp your blade is and how long it can stay sharp. Carbon is one of the essential materials that are in a blade. The amount of carbon in the steel indicates how hard a blade is. The more carbon there is, the harder it is; however, too much carbon and the blade will be brittle, prone to chipping and rusting. On the other hand, too little carbon and steel will be soft and dull quickly. There is no perfect number as the amount of carbon will depend on how experienced you are with knives and how much time you are willing to spend on maintenance. However, a good balance is around 0.8% to 1.0% carbon content. Most entry-level knives in the market contain between 0.1% and 0.3% carbon, while higher-end blades will be made of high-carbon stainless steel, such as AUS-8, AUS-10, 440C, VG-10, etc. The Japanese 440 steel used in Kotai Knives contains around 1% carbon while still being stainless thanks to the addition of 17% chromium in the alloy. Other metals such as molybdenum and vanadium can also be added to the steel alloy to increase the blade’s toughness and wear resistance.
Tempering, also known as heat treatment, is what gives the steel its mechanical properties, like hardness, toughness, and flexibility. Without proper heat treatment, the real potential of a blade cannot be achieved. If tempering is correctly executed, it will result in a good balance between hardness, toughness, and corrosion-resistance of the knife’s blade. A higher tempering temperature will produce a softer material with higher toughness. However, a lower tempering temperature will produce a harder and more brittle material. The proper vacuum heat treatment ensures that the steel's molecular structure is at its best and can reach its full potential.
Toughness is what allows your blade to survive years of abuse in the kitchen. A blade that is very sharp, but chips easily will not last long in your kitchen. Besides the carbon content that gives the steel its hardness other metals such as molybdenum and vanadium can also be added to the steel alloy to increase the blade’s toughness and wear resistance. Kotai’s 440C contains added molybdenum (0.4%) and vanadium (0.08%) which combined with its vacuum heat treatment gives the blade the extra toughness and flexibility that is crucial for a knife to last.
Corrosion resistance is essential for anyone who does not want to spend their time cleaning and oiling their knife instead of cooking. Steel composition is always about balance and compromise. If the blade's steel is high in carbon, the blade will rust more easily, and you would have to be extremely careful about washing and storage. Every knife is different; having a higher carbon content does not mean that it is not a good knife. An example of this is Japanese knives whose blades usually contain more carbon than the typical Western knife. This higher carbon makes their blades harder, and their edges stay sharp longer. The disadvantage is that it rusts faster. This is why our engineers have screened and tried dozens of different steels before selecting Japanese 440C for its extra chromium content (17%) that confers reliable corrosion resistance to the blade.
#2: Blade Geometry
There are as many blade shapes as knife brands, each with their own benefits for a specific use. Chef knives can be broadly categorized into Western knives and Japanese knives. Western knives have the advantage of being heavier, sturdier, a more powerful cut, and a curved belly perfect for mincing. Japanese knives have a thinner blade that allows them to be sharper, lighter, and a flatter edge, which allows for precise and effortless slicing. Depending on your cooking style, one might suit you better than the other.
For those of you who do not like to compromise, there is the gyuto. Many chefs consider it to be the best of both worlds, a hybrid between a German and a Japanese knife. The slightly curved belly enables the blade to rock back and forth for fast mincing, while the thin blade allows for smooth and easy slicing. A gyuto is easily recognized by its "pointed tip," used by chefs for added precision.
Bevel grind is also important when choosing a knife. While sushi chefs might prefer single bevel knives (think of it as a chisel), most chefs prefer double bevel grinds for straight cuts and easy sharpening.
Bevel grind is also important when choosing a knife. While sushi chefs might prefer single bevel knives (think of it as a chisel), most chefs have a preference for double bevel grinds for straight cuts and easy sharpening.
#3: Perfect Balance
Balance is not always considered when choosing a knife because it cannot be seen. But after hours of slicing, chopping, and mincing, balance can definitely be felt. To optimize cutting power and minimize strain on the wrist, a knife must be hefty enough (thanks to a full tang and a quality handle), and its center of gravity must be placed strategically. Most chefs like their knife's center of gravity to be right above the bolster, where the index finger is holding the knife in a pinch grip.
Heft (the knife's weight in your hand) is also crucial to how much you will enjoy using your knife. Heft must be at the right level for you to optimize its cutting power and minimize strain on your wrist. Too light, and you would have to compensate by adding wrist tension, possibly inviting injuries. Too heavy, and it will feel clumsy and tiring. A chef knife should be perfectly balanced and feel like a natural extension of your arm.
If steel is the knife's soul, craftsmanship is the knife's body, and a soul without a strong body cannot achieve much.
When it comes to sturdiness and durability, a full tang is the way to go. The tang refers to the extension of the blade that goes inside the handle. There are 2 main types of tangs: full and partial. A full tang extends all the way to the end of the handle, ensuring that the blade and handle will never part. Partial tangs are where the blade metal only extends to about half the handle's length and is cheaper to produce but more prone to loosening or even breaking after extended use.
There is actually a third type of tang: the hidden full tang. This construction type is technically much more demanding to manufacture, but the result is worth the additional cost and effort. Hidden tangs are not visible from the outside; they run inside the handle before widening at the end to form a metal cap. A hidden full tang is as durable as a full tang, with the added benefit of seamless aesthetics and comfortable round handles. KOTAI has developed a proprietary manufacturing technique to create a full tang knife without adding rivets or using glue, making it considerably more durable than other knives.
Great craftsmanship reveals itself in the smallest details, and a truly well-made knife will have a seamless construction. Small gaps between the bolster and the handle can harbor bacteria. High-end knives will have no such gaps for optimal hygiene and durability. This can be checked by running your fingers along the handle: it should be completely smooth.
Besides the raw materials used, the difference between a high-end knife and a lower-quality option is the number of hours spent on it by the knifemaker. After grinding (giving the blade its final shape), a blade can be polished once, twice, or many more times. KOTAI knives are polished by hand using 5 different wheels to obtain their distinctive "satin finish". Satin finishing offers excellent corrosion resistance by reducing the contact area between the steel and the air and minimizing the invisible asperities in which water could hide. As opposed to a mirror finishing, satin finishing is very hard to scratch, thus remaining beautiful throughout decades of use.
#5: Handle Shape & Material
Even though the blade is the first thing to look at when choosing a quality knife, you will (hopefully) have very few contacts with it. On the other hand, the handle is the only part that will sit in your hand for hours and hours. Mass-produced handles are generally made of ABS or POM (plastic polymers). They tend to be slippery - especially with wet hands - and do not look great, especially after repeated use. On the other hand, wooden handles have a timeless and classic look and offer a better grip, but wood is an unstable material that can crack, swell with humidity, harbor mold and bacteria and even give you splinters.
Following centuries of tradition, KOTAI handles are round, wooden handles. Our handles are made of pakkawood, a composite material engineered by compressing wood with resin at very high pressure and temperature. The result is a natural black pakkawood that will take a beautiful patina over the years while providing excellent grip (even with wet hands) and preventing water absorption, splinters, and bacteria. Another detail you may want to consider when choosing your knife is the handle bottom. Having a flat metal cap at the end of the handle will come in very handy when you need to crush garlic for example.
At the end of the day, knife selection is a matter of personal taste, cooking style, and subjective preference. Just keep those 5 criteria in mind to avoid disappointment, and you will be one step closer to finding your ideal cooking partner.