How Sharp Do You Need Your Kitchen Knives To Be?

[dcarch]

Branching from another knife thread: 

Posted by 

paulraphael

I think this is the root of our disagreement. Technically, yes, no one needs anything more than a knife that's somewhat sharp in order to make little ones out of big ones. But there are serious advantages to knives that are "scary sharp" by western culinary standards. In Japan, such knives would just be called knives. 

 

My point is, not “Technically”, but “practically”, 98% of the cooking needs in a normal home kitchen can be satisfied with just sharp knives. There is no need for “scary sharp” knives.

 

If you have an extremely sharp blade, whole new culinary techniques become available.

 

I have not seen many top chefs use scary sharp knives. There are so few techniques which really require an extremely sharp knife. I mean how often do you have to make Katsuramuki  daicon?

 

You're able to work with more finesse than what's possible with European techniques. It's unfortunate that the hybridized Japanese/western techniques aren't widely taught. There isn't a lot online or in cooking school. I was lucky enough to learn from a chef who'd trained in Japan. It was the second time I threw out everything I knew about cutting and started over again, and I'm pleased that I did.

 

I agree it is fun and interesting to learn exotic fancy knife skills, and it is impressive to show off what you can do with an ultra sharp blade.

 

Possibly the biggest advantage is that your cuts will be cleaner and the food that you cut will stay fresher looking and fresher tasting.

 

Fresher looking? Fresher tasting? I am not convinced there is that much difference between a sharp knife and an ultra sharp knife.

 

People don't believe me, but I can cut herbs hours before service and they will not turn brown. They will in fact not turn brown even in 24  hours (they'll eventually shrivel and dry out, or go limp and ferment, depending on climate). But I can make cuts that are so surgical that none of the oxidative enzyme reactions are triggered.

 

Turning brown has to do with chemistry, I can’t imagine cutting has much to do with it.

 

This is why sushi knives are so damn sharp—sharper even than anything I use. You don't need such a crazy sharp knife just to cut fish. But to make cuts with a glass-smooth finish, that retain their uncut flavor from the kitchen to the table, and do so to the standards of a chef who's honed his palate for such things—you need blades that are sharp as hell. 

 

I would think a rougher cut will deliver more flavor to taste receptacles.

 

The advantage I find in day-to-day cooking is mostly that I like the techniques more. ------------ I find this a lot more fun, and more interesting, and less tiring. Sometimes it's just a bonus that the cuts are all glass-smooth and surgical. 

 

I have the same problem. :-)

 

I wouldn't suggest that cutting this way is mandatory. When I staged at a Michelin 3-star seafood restaurant, I saw people using a huge variety of knife styles and cutting styles. Which suggests there's no one right answer. That said, I haven't met anyone who's learned the Japanese techniques and gone back western-style cutting ... or to western standards of "sharp."

 

I hope you don’t feel I am trying to be argumentative. I actually agree with the basics of your points. I just differ with your understanding of degrees. Yes some people can take advantage of a scary sharp knife vs a sharp knife. Like some people can tell the difference between a $100 bottle of wine and a $500 bottle of wine, but for 98% of people, a $100 bottle of wine is all they need.

 

dcarch

[Shalmanese]

There's quite a few everyday techniques where scary sharp knives can make a meaningful difference. Cutting raw meat, for example is noticeably different. Meat compresses and bulges to the extent that pressure is applied. Even a decently sharp knife will have problems cutting meat into thin slices and the commonly suggested advice is to let meat slightly freeze so the slices can be thin enough. With a scary sharp knife, you're applying almost no pressure to the meat and can cut thin slices much easier.

All I know is I've not yet held a knife and wished it could be a bit duller. Also, unlike the example of the $500 wine and the $100 wine, it's not exponentially more expensive to keep a knife scary sharp vs merely sharp. It's maybe an extra 10 minutes every month or so at most.

[Norm Matthews]

My son brought home a slab of raw pork belly with the skin still attached.  He didn't want to cut off the skin.  Every knife we tried was defeated by the flabby meat and very tough skin.  After a night in the freezer, I got out an old long, curved black steel blade and sharpened it.  That kind of steel can be easily sharpened to very sharp.  It cut through the meat but had to be re sharpened every few cuts. I tried the other knives on the meat and they still struggled to cut through the skin. That is the only time I have needed a really really sharp knife in the kitchen in 25 of so years.  I have a theory that those old high carbon knives are the ones that can turn greens brown due to their interaction with the high iron content in the knives.  I also think those knives are soft enouth that they can be actually sharpened with a steel, not just realign the edge. 

[pastrygirl]

I will offer one task for which a kind of dull knife is preferable:  cutting citrus supremes.  A sharp knife cuts into the membranes, while a not so sharp knife glides along it to separate the segments cleanly.

[dcarch]

There's quite a few everyday techniques where scary sharp knives can make a meaningful difference. Cutting raw meat, for example is noticeably different. Meat compresses and bulges to the extent that pressure is applied. Even a decently sharp knife will have problems cutting meat into thin slices and the commonly suggested advice is to let meat slightly freeze so the slices can be thin enough. With a scary sharp knife, you're applying almost no pressure to the meat and can cut thin slices much easier.

 

How many butcher shops do you think keep "scary sharp" knives?  

All I know is I've not yet held a knife and wished it could be a bit duller. Also, unlike the example of the $500 wine and the $100 wine, it's not exponentially more expensive to keep a knife scary sharp vs merely sharp. It's maybe an extra 10 minutes every month or so at most.

 

You need a lot of skills and dedication to keep your knives scary sharp, but not for "very sharp ".

 

dcarch

[gdenby]

My son brought home a slab of raw pork belly with the skin still attached.  He didn't want to cut off the skin.  Every knife we tried was defeated by the flabby meat and very tough skin.  After a night in the freezer, I got out an old long, curved black steel blade and sharpened it.  That kind of steel can be easily sharpened to very sharp.  It cut through the meat but had to be re sharpened every few cuts. I tried the other knives on the meat and they still struggled to cut through the skin. That is the only time I have needed a really really sharp knife in the kitchen in 25 of so years.  I have a theory that those old high carbon knives are the ones that can turn greens brown due to their interaction with the high iron content in the knives.  I also think those knives are soft enouth that they can be actually sharpened with a steel, not just realign the edge. 

 

At just about the same time I started to learn to sharpen my kitchen knives, and then buy better ones, I ran into the same problem. The only knife close enough to do the job was my old mainstay, a 10" Sabatier-Hofftriz. Could not cut the skin easily, and was wat to big to handle. In the end, the only thing that worked was a fresh snap off utility blade.

 

While I was learning about Japanese knives, I practiced sharpening w. an Edge Pro apex. What I found was that even if I could get them to where they could easily slice paper, some would hold that edge for as little as 4 cuts. The Sabatier could be taken down to an 18 degree bevel per side, and hold it. It is the only one of my old knives that I still use on a regular basis.

 

The only old knives I still rely on are both boning knives. One is a Dexter-Russel I bought used from a butcher, the other is an old Chicago Cutlery I bought from a thrift shop. They are still very useful if I'm slicing up a carcass, and don't want to hazard chipping a more expensive blade.

 

Once I bought knives, mostly Japanese, that would hold a 15 degree bevel, I stopped using ones w. the standard 20 - 22 degree bevels. Even freshly sharpened, they are too much of a bother to use. In other words, what I used to consider sharp does not even qualify for the term IMO.

 

I do have one "scary sharp," a gyuto that has a bevel that I think is between 10 and 12 degrees per side. And I don't use it that much. Partly because I rarely need to, partly because I don't have a good end grain cutting board, and I'm afraid I would mess up the edge using it against the boards I do have. To date, I've only needed to strop it, so don't know how hard it will be to restore the edge if I have to give it a lot of use.

 

I have a couple of "screamingly sharp" knives, a petty knife with a VG-10 core, and bunka made with R2 that is "laser" thin. One of those gets used for almost every job. I love not crying when I cut onions. I like that my apple and potato slices oxidize so much more slowly. I like being able to slice items as thin as I would w. a Benrinner mandoline that are to big for that. While both require a good bit of work if they really need sharpening, I only take them to the stones maybe 2 times a year with home use. The Sabatier-Hoffritz under the same use is about 3 times a year.

 

I should add that my hands are becoming quite arthritic, and clumsy. Every bit of effort I save in force is much appreciated.

 

And to go back to the problem Norm mentioned, I have one knife that I suppose is scary sharp just for the job. I bought an inexpensive Kai "Wasabi" short deba. Being single beveled at 15 degrees, its just the right size to slice away skin from pork belly, or picnic shoulders, and keen enough that the job isn't very hard. Also good for cutting poultry joints and tendons.

[rotuts]

this is a tiny bit OT :

 

sharp for me, and I do have the EP, and some Globals and many Graafton's knives from England,

 

is that the weight of the knife , just with a slight pull, no downward pressure

 

easily cuts a tomatoes skin.

 

cleanly.

 

no sawtooth stuff of course.

Edited October 4, 2015 by rotuts (log)

[Shalmanese]

How many butcher shops do you think keep "scary sharp" knives?

Pretty much any butcher who knows what they're doing will maintain upkeep on scary sharp knives. The usual way of doing so is buying something like Dexter Russell and sharpening every single day or sometimes multiple times a day. Take a look at this video for an example of how much easier a scary sharp knife makes the job. Or take a look inside of this chicken processing plant where the workers appear to be using scary sharp knives that take barely any pressure to cut through the chicken.

[paulraphael]

Actually, I don't think many butcher shops use especially sharp knives. They get their cutting ability from a moderately sharp but very toothy edge. Most butchers use forschner or dexter kinds of knives, sharpened on a grinder by a sharpening service, and maintained on a steel. Commercial grinders use a coarse-grit that gives a toothy edge; this does a great job ripping through the sinewy, slippery texture of raw meat.

 

A thinner edge with a mirror polish cuts even better, but the advantages are less significant with meat that's going to be cooked. 

 

Any time you see someone maintaining a knife with a butcher steel, you know it's not a very sharp edge. A thin, mirror-polished edge would get trashed by steeling. Thin edges need to be maintained on waterstones on on strops. 

 

What you're seeing in those butchering videos is the skill of person with the knife. They're slipping the blade perfectly through the joints of the chickens or between the muscle groups of the cow, so the knife has to do surprisingly little work.

Edited October 5, 2015 by paulraphael (log)

[daveb]

dcarch,

 

I'd like to add my perspective by first taking some license with your initial comment:  More than 98% of the cooking needs in a normal home kitchen are satisfied with whatever knife is available, with little to no thought of how sharp the knife is.  Only an inconsequential percentage of home cooks know how to evaluate sharpness and fewer still so anything to achieve or maintain sharpness.with their knives.  And this is not necessarily a bad thing.  

 

In a forum that favors quantitative measure over qualitative ones the notion of "sharp" "extremely sharp" "ultra sharp" "scary sharp" and "too sharp" elude definition.

 

To your question I'll suggest that my knives are sharpened to an optimal sharpness that will vary with the knife, the application and the user.  I use the grit of the final sharpening stone in the sharpening progression to quantify sharpness.

 

To wit, I have two gyuto that travel with me.  One is a stainless "laser" that I sharpen to 6K and use for slicing/dicing fruits and vegetables.  I could sharpen to 8K but the optimal edge will stay sharp for all day cutting and an 8K edge would not.  The other gyuto is stainless clad with a bit more heft that I use for all around cutting.  Hard squash, pineapples, peeling melons, cutting meat.  I finish it on a 3-4K natural stone, again so the edge will stay sharp all day.

 

I'll also carry an application specific suji (slicer) with me.  For raw proteins I have a stainless laser that I finish on either a 6K or 8K stone.  For cooked and crusted proteins I have a stainless clad that is finished on a 6K stone for a more toothy edge that will hold up longer.

 

In either case, either knife will do either task.   In each case, one of the knives is optimized to the task.

 

These knives are as sharp as they need to be but not to fragile for their application.  None of them are "ultra sharp" scary sharp" or "too sharp".

Edited October 5, 2015 by daveb (log)

[dcarch]

Here is my lesson for sharpening knives:

 

Hold a knife at an angle on a sharpening stone. Push up, pull down. Repeat if necessary.

 

People have made sharpening such an intimidating  mystifying high art. I am willing to bet you will have great difficulty to find chefs who can sharpen knives to "scary sharpness".. They all can almost sharpen knives to normal sharp, but few feel the need to shave with their chef's knives.

 

Extreme sharp blade is fun to have, fun to show off with, but it is for knife hobbyists.

 

dcarch, 

[rotuts]

"""   A thin, mirror-polished edge would get trashed by steeling. Thin edges need to be maintained on waterstones on on strops.   ""

 

i agree,

 

with very good technique i can get all my knives, including the globals to easily pass the 'tomato test' w the 600 grit 

 

EP stone.  I have the 1000 grit stone and sometimes go through that grit, but its just for incredible satisfaction i get using that stome

 

very very lightly.

 

on knifeforum, people routinely use either the EP 'diamond tapes' or the very fine chosera and Shapton stones

 

http://www.chefknivestogo.com/edgepro.html

 

http://www.bladeforums.com/forums/showthread.php/1168171-Edge-pro-blanks-stones

 

but dcarch is correct,  'hobbyists' in another dimension entirely

[paulraphael]

Extreme sharp blade is fun to have, fun to show off with, but it is for knife hobbyists.

 

 

Tell that to all the chefs in Japan.

 

Here's how I like to show off with a sharp knife: all the cuts look great, all the herbs are fresh and vibrant, even though I cut them two hours ago, I finished prepping the food 20 minutes faster than I otherwise would have been able to, I don't have to stop and steel the blade to keep the edge useable, and even if I did this all day long I wouldn't get one of those knife calluses on my index finger.

[daveb]

What's a steel?

[Hassouni]

A honing steel https://en.wikipedia.org/wiki/Honing_steel

 

Not very useful (and usually detrimental) to very hard knives such as Japanese knives.

Edited October 5, 2015 by Hassouni (log)

[dcarch]

Tell that to all the chefs in Japan.

 

Here's how I like to show off with a sharp knife: all the cuts look great, all the herbs are fresh and vibrant, even though I cut them two hours ago, I finished prepping the food 20 minutes faster than I otherwise would have been able to, I don't have to stop and steel the blade to keep the edge useable, and even if I did this all day long I wouldn't get one of those knife calluses on my index finger.

 

Assuming everything you said is true, but 98% of the knife users are not chefs, and that's my whole point. For a normal cook, in a normal home kitchen, a very sharp knife is very sufficient.

 

dcarch

[daveb]

A honing steel https://en.wikipedia.org/wiki/Honing_steel

 

Not very useful (and usually detrimental) to very hard knives such as Japanese knives.

 

Thanks but I was making a funny...

[gdenby]

Assuming everything you said is true, but 98% of the knife users are not chefs, and that's my whole point. For a normal cook, in a normal home kitchen, a very sharp knife is very sufficient.

 

dcarch

 

As a young fellow said to me a few years ago, "Your generation was lucky, it learned how to make mac and cheese from a box." I replied "How so?" "Your generation at least had to learn to boil water, my generation would starve it they couldn't toss something into the 'wave."

 

So I suppose I must agree, even a just sharp knife is adequate for most contemporary home cooks.

 

But my mother, who was a good home cook, would run her Sabatier thru an electric sharpener frequently, and sometimes steeled the blade several times during the course of a large dinner. She would never have considered herself to be a chef. Still, she required an edge comparable to what is still considered sharp, i.e. about 20 degrees per bevel.

 

To quantify, I call standard edge bevels at 20 - 22 degrees per side sharp. Very sharp is 15 - 18. "Screaming" sharp around 12. "Scary" below 12. For my home use, I avoid anything that is not at least very sharp. They are just too clumsy.

[paulraphael]

Assuming everything you said is true, but 98% of the knife users are not chefs, and that's my whole point. For a normal cook, in a normal home kitchen, a very sharp knife is very sufficient.

 

dcarch

 

We probably agree about that, although I don't like putting people in boxes like "normal cook." It seems more about priorities and temperament than anything normative.

 

I actually like the working style and esthetic of the European knife and Cordon-Bleu techniques. The idea of a jack-of-all-trades tool (chef's knife) that always does your bidding and can be quickly and simply maintained (steeling) appeals to me tremendously. The question is if the appeal of Japanese-style cutting and sharpening techniques outweigh the costs—which I see as additional education and a more heightened need for attention.

 

Different cooks are going to answer that differently, but I don't think it has to do with who's more "normal" or who's more professional. I think I'd mentioned in an earlier post that at a Michelin 3-star seafood restaurant where I staged, I saw all kinds of knives and all kinds of techniques. Everything from garden-variety Wusthoff to laser-thin gyutos with wa-handles.

 

What I'm getting at, is that it's for the cook to decide. The benefits to sharp knives (in the Japanese sense) are real. So is the investment in new skills, and the added attention they require. No one can make the cost/benefit analysis for you.

Edited October 6, 2015 by paulraphael (log)

[dcarch]

paulraphael

 

I don't know if you will agree with me on this one. I once in a while have to cook in someone else's kitchen. What drives me nuts is that I always have to bring my own knives. I can guarantee you that 98% of the kitchens have very dull knives.

 

I also, once in a while, bring along a sharpening stone and sharpen a few of their knives to show them how easy it is to put a useful edge on a knife.

 

People will spend $$$$$$$ on a kitchen renovation, but they pay no attention to the most important tools in a kitchen, namely the knives.

 

dcarch

[paulraphael]

Yes, that's my experience as well. I think it's just something that people aren't educated about, and don't want to be educated about. The topic bores them. They want to have a Good Knife, but don't want to pay any attention to it. Use it on glass cutting board, throw it in the sink, the dishwasher, the drawer, and maybe five years from now say "huh, maybe I should get this thing sharpened."

 

This is why I bring my knives when I go anywhere to cook, and why people who come to help cook in my kitchen they use my girlfriend's knives (she doesn't care) and not mine. Unless they care enough to let me teach them. Which has happened maybe twice ever.

 

But in my pontifications about very sharp knives vs. sort-of sharp knives, I wasn't even thinking about the typical home knife drawer. Those knives don't even have edges on them. By sort-of sharp, I'm talking about those knives when they were brand new, or when freshly sharpened on a coarse stone or ceramic rod.

[Robenco15]

I need/prefer my knives to be very sharp (scary sharp?). This past weekend I stropped my Konosuke HD2 of 1.25 years to a mirror finish and was able to perform the tomato test exactly as I did the day I got it. The knife is amazing and with proper stropping, I've never actually had to sharpen it on stones. It is unreal. I use it for produce and meat to whole watermelons and pineapples. There isn't much I don't use it for.

 

In my mind here are the benefits of having a very sharp knife:

 

A sharp knife makes me want to get in the kitchen more so than I already want to. It makes doing all of my prep an absolute joy. It makes everything look better as my cuts are more precise and even. It makes everything go quicker (and therefore even more enjoyable).

 

A sharp knife is one of the best parts about cooking. It removes any thought that cooking is a chore and continues to make cooking an enjoyable after work activity.

 

I disagree with the notion that crazy sharp knives are only for "hobbyist." If I gave my extremely sharp knife to my Mom, I doubt after using it she'd want to give it back.

 

p.s. the tomato test (not me, but what I do as well) -

[Porthos]

This is why I bring my knives when I go anywhere to cook ...

Yup.

Edited October 7, 2015 by Porthos (log)

[rotuts]

I like that Tomato Test

 

Ill be trying it soon

 

any idea which knife is being used ?

[Robenco15]

Rotuts, it's a Konosuke HD. That exact model is no longer made, but they now make a Konosuke HD2, which is what I own and love. It is crazy sharp and is a laser (crazy thin at the edge). Somewhat expensive, but I've loved every moment with it.

 

http://www.chefknivestogo.com/kohdwa24.html