The real reason your kitchen knife has strange little grooves — and it's genius

If you have ever looked at one of your kitchen knives and noticed a series of tiny, oval hollows on the blade, and then quietly decided they were just for show, you are in very good company. Most people do. Those little grooves are one of the most underrated pieces of engineering sitting in your knife block. Once you understand what they do, you're going to reach for that knife a lot more.

They call it the Granton edge. It was patented in 1928 by William Grant at his family’s cutlery business in Sheffield, England, and has been quietly fixing one of the most annoying problems in everyday cooking ever since.

What really happens when food sticks to your knife?
This is a feeling we all know. You are slicing potatoes for a gratin or slicing a cucumber into thin rounds, and every single slice just sticks to the blade. You have to peel each piece off before you can make the next cut. It’s frustrating, it slows you down, and it makes clean, even slices almost impossible.


This happens because of moisture and surface area. When you drag a flat blade across a flat, moist surface, such as a slice of potato or a tomato, the moisture between the two surfaces creates suction. According to research published in the journal Theoretical and Applied Fracture Mechanics, friction and the contact surface area between a blade and food material do have a measurable impact on cutting resistance. One of the most effective ways to get a cleaner cut is to reduce that contact. The hollows along a Granton edge do just that. They break up the surface contact, create tiny air pockets between the blade and the food, and effectively interrupt the suction before it can form.

Another paper published in the journal Materials on the efficiency of food cutting also found that reducing friction and pressure between a blade and the food material directly reduces resistance during the cut, resulting in less drag, less sticking, and greater control for the person holding the knife.

The daily payoff is real
That’s not an insignificant difference. When you get a Granton edge knife and start using it for the right tasks, the improvement is obvious. It works particularly well on starchy or wet foods like potatoes, cucumbers, and beets, where the sticky-slice problem is worst. Also, if you’re carving roast meats, such as turkey or ham, it’s a noticeable benefit to get clean, intact slices that won’t tear through the grain.

The same logic applies to fruit, proteins, and vegetables. Strawberries, peaches, apples, or anything with a bit of juice tend to stick to a flat blade. The Granton edge just avoids that altogether. Cutting a block of cheddar is smoother and even. Cheese has enough fat content to create the same surface-tension problem.

Why most home cooks still don’t use it
Part of the issue is that the Granton edge shows up on knives that don't always get pulled out first. You often see it on carving and slicing knives, those long, thin blades that live in the back of the knife block and only get pulled out on Thanksgiving, but you’ll also find the design on santoku knives, which are actually a great everyday choice if you want a knife that can handle most prep work with less hassle.

The other thing is that most people really don't know what those grooves are for. They look decorative, or like a serrated edge that just isn't quite finished, so the knife gets passed over for a plain chef's knife out of habit.

The fix is simple
Get to using it. Take out any knife you have with those hollows down the blade and just run it through a potato or a cucumber. The slices will release cleanly from the blade, and your cuts will be more even and faster because you won’t have to stop every few seconds to peel food off the knife.

The Granton edge is approaching a hundred years old, and it still solves the same problem that it was designed to solve. That's not a coincidence; it's just good engineering that most of us were never told about.