A SHARP KNIFE IS A SAFE KNIFE!
Keeping a sharp edge on your blade is important for your own safety. Compensating for a dull edge by applying additional force to finish a cut is where serious injuries can occur. If the knife blade is unexpectedly freed from what you are cutting, there is often an ongoing momentum that can slash you.
The first thing to understand is how knives actually become dull. The two main reasons a knife becomes dull is either a rolled edge or an edge that has become rounded. To understand both, you need to consider that while the knife edge may look uniform to the naked eye, the actual edge is quite thin and jagged at the microscopic level.
A rolled edge is when the edge becomes bent or rolled over to one side and is caused by physical pressure on the edge of the blade. If you can imagine pressing a fork into a brick, the bending of the fork is exactly what happens to the edge of the knife on the microscopic level. This is the most common reason that knives become dull.
A rounded edge is when actual material is removed from the blade due to friction, tearing or abrasion. In English, this is normal wear and tear on your knife from slicing food, chopping against your cutting board or even from corrosive effects due to the acids in your foods (tomatoes are notorious for this). When your knife edge becomes rounded, this is when your knife requires actual sharpening by grinding down the edge.
For those who use their knives on a regular basis, we recommend using a sharpening steel once a week to maintain the sharp edge. Once the sharpening steel no longer has an effect on the knife, a stone or pull-through sharpener should be used to produce a new cutting edge.
The best sharpening edge is 15-degree angle.
How to Tell If Your Knife is Sharp Enough
PUT THE BLADE TO THE PAPER TEST
Even the best knives will dull over time with regular use. To determine if your knife needs sharpening, put it to the paper test. Hold a folded, but not creased, sheet of newspaper by one end. (You can also use a single sheet of basic printer/copy paper.) Lay the blade against the top edge at an angle and slice outward. If the knife fails to slice cleanly, try steeling it (see below). If it still fails, it needs sharpening
We strongly recommend using manual, not electric sharpeners. It’s too easy for a home cook to get carried away, exerting too much pressure and making too many strokes, while the whirling machine eats the edge off your knife. With a manual sharpener, use gentle pressure while pulling the knife through, and test often as you go.
A- Electric Knife Sharpeners
With electric sharpeners, the abrasives are on motorized wheels that spin against the blade. Always follow the manufacturer's instructions. In general: Turn on the sharpener, hold your knife securely but lightly (no need to press down hard; the machine does the work for you), and pull the blade through the desired slots slowly and smoothly. Alternate sides for sharpening both sides of your blade.
B- Manual Knife Sharpeners
With manual sharpeners, the abrasives are either on non-motorized wheels or the abrasive material itself is fashioned into a V-shaped chamber through which the user pulls the knife. In general, pull the blade through the chamber with even pressure. Always follow the manufacturer's instructions.
A particular gentle and effective way of sharpening knives is to maintain their edge using a whetstone.
How to use the whetstone
- Submerge the whetstone in water for about five to ten minutes to soak. When there are no more little air bubbles appearing, the stone has absorbed the optimum amount of water.
- Continue to apply water whilst sharpening. The water combines with small particles released from the stone to form an abrasive substance, which allows the sharpening to take place.
- Place the stone on a slip-resistant base.
- Start by using the coarse grit of the stone.
- Move the blade back and forth (away from and towards the body) at an angle of 15 - 20° across the entire stone.
- Use light pressure.
- Start at the tip of the blade. Pull the blade over the stone through to the middle and down to the base of the blade. After a short time, a fine edge will have developed.
- Turn the knife around and work on the other side of the blade.
- Repeat this process several times as necessary.
- Important: Always maintain the same angle.
- To finish, pull the blade twice at an angle to the cutting edge to remove the last burrs. Your knife should now be really sharp.
- Rinse off the whetstone and clean off the grinding residue.
- Rinse the knives carefully in hot water.
Check our article about whetstones type in here
Many people don’t know the difference between honing and sharpening. But they are equally important for efficient knife work. Honing, which makes the blade of a knife straight, is done with what’s often (and incorrectly) called a sharpening steel, by drawing the blade over and over along an abrasive rod of metal, ceramic, or stone. Many professionals hone their chefs’ knives daily, but doing it weekly is plenty for most home cooks. It’s a quick process once you feel confident – and it’s fun, making you look, feel, and sound like a serious cook. But remember: honing helps maintain the blade’s sharpness, but doesn’t actually sharpen it.
How to Use a Knife Sharpening Steel
- To safely use a steel, hold it vertically with the tip firmly planted on the counter. Place the heel of the blade against the top of the steel and point the knife tip slightly upward. Hold the blade at a 15‑degree angle away from the steel.
- Maintaining light pressure and a 15‑degree angle between the blade and the steel, slide the blade down the length of the steel in a sweeping motion, pulling the knife toward your body so that the middle of the blade is in contact with the middle of the steel.
- Finish the motion by passing the tip of the blade over the bottom of the steel. Repeat this motion on the other side of the blade. Four or five strokes on each side of the blade (a total of eight to 10 alternating passes) should realign the edge.
How to Sharpen Serrated Knives
Sharpening a serrated knife is much different than sharpening a traditional straight blade. Each individual serration will need to be sharpened separately. Because a serrated knife functions like a saw, it can often still cut when dull. However when dull, it will tear or shred rather than cutting smoothly.
Note: Serrated knives are harder, if not impossible, to sharpen unless you send it to a pro who has the tools to do it.
Which kind of knife sharpener do you have? How is your experience with the sharpening of knives?