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If you love cooking, you’ll know how important it is to have the right knife for the job, and if you’re in the market for a new all-rounder, don’t miss our rundown of the best chef knives of 2021.
For many people, a ceramic knife is a kitchen must-have, but despite their popularity with some, these modern blades also have their critics. Find out if a ceramic knife is right for you with our ultimate guide.
Ceramic knives have blades made from a special, toughened ceramic. Using ceramic to make blades is less strange than it might sound, as it is actually an extremely hard material and can be used to make an ultra-sharp precision blade that stays sharper for longer than steel.
Hardness is not the same as toughness, however, and as we all know, ceramics can be very fragile and prone to shatter. Because of this, ceramic knives use an ‘advanced ceramic’ called Transformation Toughened Zirconia, or TTZ, which is treated with heat and pressure to make it tougher, and is often used in dentistry to make crowns and bridges.
TTZ is almost twice as hard as regular steel, and far tougher than regular ceramics, but ceramic knives are still more fragile than regular knives, and require specialist care. So is it really worth investing in a ceramic knife? We take a look at some of the pros and cons to try and find out.
The most obvious advantage of the ceramic knife is its ultra-sharp blade. It can go for years without needing to be sharpened, staying razor-sharp for up to 10 times as long as a steel blade, by some estimates.
Ceramic is a lightweight material, making it easier to manipulate than steel. It is faster and more efficient at delicate, precision knife work, cutting through vegetables like butter, and making light work of dicing something delicate like a tomato without bruising or crushing it. Some cooks also find this to be a drawback, however, as it means you need to apply more pressure and can lead to tired hands.
Ceramic is also an inert material, and will not react with other materials. This means that it will not rust or stain and is immune to corrosion caused by caustic or acidic foods. This protects your food as well as the blade, as steel knives can sometimes transfer ions to your food, leaving a metallic taste or smell, or causing sliced fruit to oxidise and turn brown more quickly.
Finally, ceramic is non-porous, so there are fewer places for bacteria to lurk. It also makes the blade easier to clean, and means that unpleasant smells won’t linger.
The major drawback to ceramic knives is that they can be quite brittle. Despite being made from tougher advanced ceramics, they are still more fragile than steel knives, and need special care to avoid chipping, or even breakages.
A ceramic knife cannot be used for jobs that require twisting or prying, or on anything hard, like frozen food or meat on the bone. It also requires a block so it doesn’t get chipped in the cutlery drawer, and should be washed by hand so it doesn’t chip in the dishwasher. Critics have suggested that a ceramic blade may need sharpening more often than you might think, to even out chipping, and there are also safety concerns regarding small shards of sharpened ceramic getting lost in your food.
While ceramic knives may need less sharpening than their steel counterparts, when the time does come to have them sharpened, it is a far more complicated process. A ceramic knife cannot be sharpened using a regular whetstone or honing rod, and if you want to sharpen it at home you will need to purchase specialist equipment. Many people send their ceramic knives away to be professionally sharpened, which can be costly and time consuming.
Because they are more breakable than steel knives, it is a good idea to keep your ceramic knife in a knife block, so it isn’t rattling around loose in a cutlery drawer. You should avoid putting it in the dishwasher for similar reasons. Luckily, ceramic knives are easy to clean using warm water and a mild detergent.
Ceramic knives are not suited to every job in the kitchen, and should be used as a specialist knife for dicing and chopping with precision. They make light work of fruit and vegetables, and are especially good for acidic citrus fruits that can ruin steel blades. If you like making sushi, a ceramic blade is ideal for all that intricate knife work.
They are unsuited to anything hard like bones or frozen food, however, and should not be used for deboning, or anything that involves wiggling the knife, using it to prize things, or laying it on its side to crush things.
If you do decide to buy a ceramic knife, it is best to opt for a reputable brand that uses quality materials and design, to minimise the risk of breakages. You should also choose a knife with a well-designed, ergonomic handle that’s easy to hold, and won’t leave your knuckles dragging across the cutting board. We recommend a blade of 7 inches or less, as this is the best length for the precision dicing to which the ceramic knife is best suited.
What should I do if my ceramic knife gets chipped?
Smaller chips may be repaired by having your knife sharpened, which essentially smooths away the damage. This will not always be possible, especially for larger chips, but in general, anything up to 10mm on the tip of the knife, or 3mm on the edge should be repairable.
What should I do if my ceramic knife is broken?
A broken ceramic knife is potentially dangerous. If you have a broken ceramic knife then unfortunately, your only option is to throw it away.
Can I sharpen my ceramic knife at home?
Ceramic knives cannot be sharpened using a regular whetstone or honing rod, and while you can buy specialist sharpening tools, they tend to be quite expensive. Many ceramic knife manufacturers offer specialist sharpening services, so you can send your knife away to be sharpened.
Are ceramic knives dishwasher-safe?
Technically speaking, ceramic knives are dishwasher safe, but they are particularly brittle, so putting them in the dishwasher can be risky. To avoid any potential breakages, hand wash your ceramic knife using warm water and detergent.
