Wash by Hand
Use mild dish soap, warm water, and a soft sponge or cloth. Keep your fingers away from the edge and wash from the spine toward the edge rather than along the cutting edge.
TETSU & OAK KNIFE GUIDE
Japanese Knife Care & Maintenance Guide
A Japanese kitchen knife can provide years of excellent service when it is cleaned, stored, used, and sharpened correctly. This guide covers the everyday habits that protect the edge, prevent corrosion, and reduce avoidable damage.
THE FIVE ESSENTIAL RULES
- Hand wash the knife immediately after use.
- Dry the blade and handle completely.
- Use a wood, rubber, or soft-plastic cutting board.
- Avoid bones, frozen food, hard pits, prying, and twisting.
- Store the edge and tip safely.
EVERYDAY MAINTENANCE
Clean and Dry the Knife Promptly
Most corrosion, staining, handle damage, and accidental edge damage can be prevented through simple daily habits.
Dry Immediately
Dry the blade and handle completely with a clean towel. Do not leave the knife wet on the counter, in a drying rack, or inside a sink.
Store Safely
Protect the entire edge and tip using a suitable knife block, saya, blade guard, knife roll, or magnetic strip.
Inspect Regularly
Check for chips, rolls, rust, loose handles, or damage before use. Small problems are easier to correct before they become serious.
Never place a quality kitchen knife in the dishwasher.
Dishwashers expose the blade and handle to heat, harsh detergent, moisture, vibration, and contact with other objects. This can dull the edge, stain the blade, loosen the handle, and damage the knife.
PROTECT THE EDGE
Choose the Right Cutting Board
The cutting surface has a major effect on how quickly a knife becomes dull or damaged.
Wood
Quality wood boards are gentle on knife edges and provide a stable, comfortable cutting surface. Keep them clean, dry, and properly maintained.
Soft Rubber
Rubber boards are popular in professional kitchens because they are edge-friendly, stable, and relatively easy to clean.
Soft Plastic
A quality soft-plastic board can be practical and hygienic. Replace it when deep grooves become difficult to clean.
Glass, Stone & Ceramic
These hard surfaces can dull or chip a fine edge very quickly. They may look attractive but are unsuitable for regular knife use.
Board technique matters too.
Avoid scraping ingredients sideways with the cutting edge. Turn the knife over and use the spine, or use a bench scraper to move food.
SAFE STORAGE
Protect the Edge, Tip, and People Around It
Saya or Blade Guard
A fitted saya or quality blade guard protects the edge and tip during drawer storage, transport, or use inside a knife roll.
Magnetic Strip
A suitable magnetic strip keeps knives visible and accessible. Place and remove the knife carefully so the edge does not strike the strip.
Knife Block
A clean block can provide secure storage. Horizontal slots or edge-up designs reduce contact between the edge and the block.
Knife Roll
A knife roll is useful for culinary students and professionals. Each blade should still be secured so it cannot slide out or cut the roll.
Never store an uncovered knife loosely in a drawer, bag, or box.
Loose storage can damage the edge, break the tip, and create a serious injury risk.
CARE BY STEEL TYPE
Stainless and Carbon Steel Need Different Habits
All knives benefit from prompt cleaning and drying, but reactive carbon steel requires additional attention.
Easier Maintenance
Stainless steels such as VG10, Ginsan, Sandvik 19C27, and 420J2 resist corrosion better than traditional carbon steel.
- Hand wash and dry after use.
- Do not assume stainless means rust-proof.
- Avoid prolonged exposure to salt, acids, and moisture.
- Do not leave the knife soaking.
More Reactive
Aogami, Shirogami, and other carbon steels can take excellent edges but may patina, stain, or rust if neglected.
- Rinse and dry promptly during extended prep.
- Be especially careful after acidic foods.
- Expect a grey, blue, or dark patina to develop.
- Remove orange or red rust promptly.
A Mixed Construction
Stainless cladding protects much of the blade, but the exposed carbon core near the cutting edge can still react and rust.
- Dry the entire knife thoroughly.
- Inspect the exposed edge regularly.
- Follow carbon-steel habits even if most of the blade is stainless.
- Use oil for longer storage when appropriate.
PATINA OR RUST?
Learn the Difference
Patina
A patina is a stable grey, blue, purple, or dark discolouration that can develop on reactive carbon steel. It is a normal result of use and may help reduce future reactivity.
Active Rust
Orange, red, rough, or powdery corrosion is active rust. Remove it promptly using an appropriate rust eraser or other suitable method, then clean and dry the blade.
When uncertain, stop using the knife and ask for guidance before using an aggressive abrasive that could scratch the blade finish.
EDGE MAINTENANCE
Sharpening, Honing, and Touch-Ups
A knife should be sharpened when its performance declines, not only when it becomes completely dull.
Sharpening
Sharpening removes a controlled amount of steel to restore the edge. Japanese whetstones allow the angle, finish, and edge geometry to be adjusted for the knife and its intended use.
Honing
Honing is not the same as sharpening. A fine ceramic rod may help maintain some double-bevel knives between sharpenings, but aggressive grooved steels can be unsuitable for thin, hard Japanese edges.
Stropping
Light stropping can refine or refresh an edge, but poor technique or excessive pressure can round the apex. It is not a substitute for sharpening a truly dull knife.
Professional Service
Professional sharpening is useful when the knife is chipped, uneven, very dull, single-bevel, unusually thin, or when you are unsure of the correct angle and technique.
Professional whetstone sharpening in Niagara
View Pricing & Drop-Off Details
Tetsu & Oak offers sharpening, minor repairs, and temporary drop-off and pickup in Thorold.
PREVENT DAMAGE
What Fine Japanese Edges Should Avoid
Bones
Do not use a standard gyuto, santoku, bunka, nakiri, or petty knife as a bone cleaver.
Frozen Food
Frozen ingredients can chip or crack thin, hard edges and should be fully thawed before cutting.
Hard Pits and Shells
Peach pits, avocado pits, hard shells, and similar objects can damage the edge or tip.
Prying and Twisting
Do not use the blade or tip as a lever. Keep the knife moving straight through the cut.
Sideways Scraping
Scraping the edge across the board can roll, dull, or chip the apex. Use the spine or a bench scraper.
Unstable Work Surfaces
Place a damp towel or non-slip mat beneath the cutting board so it cannot move during use.
HANDLE CARE
Maintain Wood and Pakkawood Handles
Natural Wood
Keep the handle clean and dry. When it begins to look or feel dry, apply a small amount of food-safe mineral oil or another suitable food-safe conditioning product.
Pakkawood
Pakkawood is generally more moisture resistant than untreated natural wood, but it should still be hand washed, dried promptly, and kept out of the dishwasher.
Loose or Cracked Handles
Stop using the knife if the handle becomes loose, cracked, swollen, or damaged. Repairing it early can prevent further damage or injury.
COMMON QUESTIONS
Japanese Knife Care FAQ
How often should I sharpen my Japanese knife?
Sharpen when cutting performance noticeably declines. Frequency depends on the steel, edge geometry, cutting board, technique, and how often the knife is used.
Can I use a honing steel?
Aggressive grooved steels may be unsuitable for thin, hard Japanese edges. A fine ceramic rod can work for some double-bevel knives when used lightly and correctly, but it does not replace sharpening.
Can I put my knife in the dishwasher?
No. Dishwashers can dull the edge, damage the handle, encourage corrosion, and cause the knife to strike other objects.
Why is my carbon-steel knife changing colour?
A grey, blue, purple, or dark patina is normal on reactive carbon steel. Orange, red, rough, or powdery corrosion is active rust and should be removed promptly.
Can I cut frozen food with a Japanese knife?
No. Frozen food can chip or crack a thin, hard edge. Allow ingredients to thaw completely or use a tool designed for the task.
What should I do if the knife chips?
Stop using it and avoid trying to bend or break the damaged area. Small chips can often be repaired during sharpening, while larger damage may require thinning or reprofiling.
How should I transport knives for sharpening?
Knives must be clean, dry, and fully secured in a blade guard, knife roll, original packaging, or rigid cardboard taped around the entire blade. Never transport an exposed knife.
NEED HELP WITH YOUR KNIFE?
Ask Tetsu & Oak
Contact us about sharpening, chips, rust, care products, storage, or choosing the right maintenance approach for your knife.