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Jay
04-05-2011, 07:36 PM
From Anthony Bourdain's Medium Raw:
The very essence of knife maintenance--a notion inextricably tied up with one's self-image as a cook--is that the sharper the knife, the better.

He then offers this different opinion from an expert on breaking down fish, in this case regarding the extremely cartilaginous skate:

"I like medium sharp. Too sharp? You get part of the bone. When it's sharpened correct, it passes over the bone."

Your thoughts?





Before you dismiss this claim outright, you may choose to consider the source of the quote:
Justo Thomas, the man who cuts every piece of fish prepared by Le Bernardin- over 700 pounds a day, and half a ton on Friday.

Pensacola Tiger
04-05-2011, 07:41 PM
This has been remarked on by Jon Broida when he discussed sharpening with Japanese chefs. Too sharp a knife, and it "runs away".

FryBoy
04-05-2011, 08:17 PM
That makes sense -- if you're blind, lack feeling in your hands, and are in too much of a hurry.

JBroida
04-05-2011, 08:26 PM
This has been remarked on by Jon Broida when he discussed sharpening with Japanese chefs. Too sharp a knife, and it "runs away".

Its important to note a few things about this... first, the concept of what is sharp to me and the chefs i was talking to is likely drastically different from bourdains fish guy. Second, the edges can still be very sharp, they just need some bite to them. The bite helps improve feeling in the cut.

With slippery or super smooth edges, that feeling is not there. I get bite from a 15000 grit stone, but most of the chefs i spend time with in japan finish with something in the 8k range (or a natural in a slightly higher range)

I'm not suggesting anyone use a not sharp edge... i'm just suggesting that you use a sharp edge with bite versus a sharp edge that is smooth and slippery

jaybett
04-05-2011, 09:32 PM
I'm not suggesting anyone use a not sharp edge... i'm just suggesting that you use a sharp edge with bite versus a sharp edge that is smooth and slippery

What! I wish you would have told me this, before I went and dulled the edges on all my knives. :slaphead:

Jay

I didn't dull the edges on my knives

Eamon Burke
04-05-2011, 10:52 PM
I think that is just because he is used to using a duller knife, and the angle he holds it against the bone works like the Bic Pen test. The more acute knife will work just fine, and the front of the edge will face more in the direction of the motion.

This is something that I love to emphasize--There are a whole set of skills for working with a dull knife that don't apply to a sharp one. I've seen cooks do things with dull knives that sharp knives would just lop off your finger doing.

That said, I think there are a legion of reasons to use a sharp knife instead, and learn to do things differently. I am working on setting up a class for local foodies that is called "How to use a sharp knife", because knife skills for a sharp knife are very different. For example, having a locked-on death grip isn't as mandatory for a well sharpened edge, because you won't be fighting with it to get through food. This is why Hatchets have rubber handles and scalpels have plastic sticks.

Eamon Burke
04-05-2011, 10:56 PM
Caveat:
I have "over-sharpened" a knife recently. It was a Chicago Cutlery and I was showing off my abilities to refurb a knife to a friend and before I gave it back, I REALLY put it through the paces getting a super buffed edge on it. It was hair-popping sharp. Put it to some food, and it wouldn't cut ANYTHING. It was as good as a dull knife, plus wedging. I took it to my 1k stone and scratched up the bevel, stropped it on 2micron SiC on rough-side leather...it cut like a dream, as long as it was moving. It would still shave, but it wasn't as hair-popping sharp, but the knife itself didn't have the geometry to make a real push cutting edge work.

stereo.pete
04-06-2011, 09:55 AM
I ran into something similar to this recently. Now granted my sharpening skills are primitive but I found this to be interesting none the less. I have a Wustorf Classic Icon Chef's knife that I use as a beater even though it is a very nice knife, albeit heavy. My every day knife is a Fujiwara FKH Gyuto that I sharpen with 1k, 2k and finally 5k shapton pro's with leather strop and dave's diamond spray. Long story short, my Fuji never seems to hold an edge very long at all, could be the reactivity of the carbon steel as I cut a lot of onions and citrus at home ( I'm only a home cook). Well, I decided to take out my Wustorf and cut up some tomatoes because my Fuji was failing and I was absolutely amazed at how effortless it was to cut thin slices of tomatoes with my heavy German clunker. Now I only take my Wustorf up to 1k as I have been told any higher is a waste of time with soft German steel. Needless to say I was blown away at how sharp my Wustorf still was because I hadn't sharpened it in over three months and it has one of the most ugly multi-faceted bevels I had ever put on a knife :) .

I decided to sharpen my Fuji two days ago and only took it up to 1k and then stropped on a .25 diamond leather strop and it is cutting through tomatoes far better than when I take it to 5k. Is this because tomatoes need a toothier edge or is it because my sharpening skills are just that bad that I really can't take advantage of the benefits of a 5k polish?

Dave Martell
04-06-2011, 10:14 AM
Pete, tomatoes like a toothy edge - true, but I also suspect that you're creating a multi-faceted bevel (through natural wobble) that when polished to 5k becomes somewhat rounded or convex thus slippery. You may see this work different on different knives that have different steels though, ie - finer grain may result in smoother edges when polished.

stereo.pete
04-06-2011, 10:34 AM
Thanks Dave,

I think I should have been a Jeweler by trade after seeing the "amazing" multi-faceted bevels I can put on knives :) .

Andrew H
04-06-2011, 11:12 AM
I think that is just because he is used to using a duller knife, and the angle he holds it against the bone works like the Bic Pen test. The more acute knife will work just fine, and the front of the edge will face more in the direction of the motion.


Did you read the spoiler? He is one of the best in the world at breaking down fish.

iceman01
04-06-2011, 03:18 PM
I like testing for bite using paper.
I tried downgrading a knife by polishing it up to 12k and then successively going back to coarser stones. Cutting paper between each downgrade gave me the feel how much the bite can increase without the knife loosing sharpness.

aser
04-06-2011, 04:56 PM
Bourdain worked Justo into a quickfire challenge for this season's Top Chef all stars. The contestants watched him break down fish, then it was their turn....

http://www.youtube.com/watch?v=BZarDNgM2Bo

http://eatocracy.cnn.com/2011/02/25/the-fish-butcher/

Dave Martell
04-06-2011, 05:41 PM
I like testing for bite using paper.
I tried downgrading a knife by polishing it up to 12k and then successively going back to coarser stones. Cutting paper between each downgrade gave me the feel how much the bite can increase without the knife loosing sharpness.

That's a good test. Everyone should try this sometime.

Eamon Burke
04-07-2011, 12:49 AM
Did you read the spoiler? He is one of the best in the world at breaking down fish.

Never said he wasn't skilled, just that he has a different skill set. He is used to doing it one way, and perhaps he can cut fish better than any other human on the planet. Doesn't mean that he knows how to do it every way. He was stating that he prefers a "medium sharp" knife, which doesn't have any defined meaning, he was being colloquial--he is a cook, after all.

My point was, a more acute knife will work just as well--but Bourdain's man doesn't prefer it, and I posit that it is because it is simply not what he is used to. It's like a some people putting cream in their coffee before the sugar, and vice versa. You get the same results, but people do it differently.

Abattoir
04-07-2011, 04:16 AM
The only time that I do find it helpful for a knife to not be super hair popping sharp is when separating large muscle groups & silver skin from leg meat of say a pig or beef quarter. I feel like it makes cleaner work separating the muscles from the leg by taking them off the bone in whole pieces, I feel like a super sharp knife can simply glide right through the delicate membrane and silver skin, when all I need it to do is just help me split them apart. Just my .02.

iceman01
04-07-2011, 06:36 AM
I like testing for bite using paper.
I tried downgrading a knife by polishing it up to 12k and then successively going back to coarser stones. Cutting paper between each downgrade gave me the feel how much the bite can increase without the knife loosing sharpness.

That's a good test. Everyone should try this sometime.

Everybody knows to test sharpness by cutting paper. You are after the feeling and sound that the edge cuts the paper instead of tearing it apart. When it comes to bite your ears and hands can trick you. You don't feel the knife gliding through the paper like a warm knife through butter. You hear a sizzling noise but that's not dullness, that's the bite on a very sharp knife.

festally
04-07-2011, 11:11 AM
I don’t butchered fish much, but can relate to what he’s saying. I used to intentionally dull my knife by slicing into the cutting board a few times cause I could feel it riding along the skin and ticking against the pin bones - better. Otherwise, it would cut through the skin and bones too easily.

I like stupidly sharp, highly polished edge that can whittle hair as much as anyone, just not for certain tasks. I prefer a less refined / toothier type edge when cutting fibrous things like rope, cardboard, and my sister-in-law’ roasts.

Dave Martell
04-07-2011, 11:14 AM
Everybody knows to test sharpness by cutting paper. You are after the feeling and sound that the edge cuts the paper instead of tearing it apart. When it comes to bite your ears and hands can trick you. You don't feel the knife gliding through the paper like a warm knife through butter. You hear a sizzling noise but that's not dullness, that's the bite on a very sharp knife.


I wasn't referring to the paper part (per Se) but that you tested between stones to feel the difference.

Andrew H
04-07-2011, 11:21 AM
Never said he wasn't skilled, just that he has a different skill set. He is used to doing it one way, and perhaps he can cut fish better than any other human on the planet. Doesn't mean that he knows how to do it every way. He was stating that he prefers a "medium sharp" knife, which doesn't have any defined meaning, he was being colloquial--he is a cook, after all.

My point was, a more acute knife will work just as well--but Bourdain's man doesn't prefer it, and I posit that it is because it is simply not what he is used to. It's like a some people putting cream in their coffee before the sugar, and vice versa. You get the same results, but people do it differently.

Not to be offensive, but the reason I believe him is because he breaks down 700 pounds of fish a day at (arguably) the top seafood restaurant in the world. Why do you think a more acute knife will work?

Eamon Burke
04-07-2011, 07:20 PM
Not to be offensive, but the reason I believe him is because he breaks down 700 pounds of fish a day at (arguably) the top seafood restaurant in the world. Why do you think a more acute knife will work?

It will work because it is a sharp knife. Just like the more obtuse angle. I'd draw a diagram, but I am not on the right computer. The point is, using the technique he *prefers*, he doesn't hit the cutting edge with the fish bones--to do the same thing with a more acute edge, you just attack the fish with a more acute angle relative to the bone. A knife that will not cut paper at all will still stick to a BIC pen, it'll just be almost completely perpendicular to it. It's not about what works and what DOESN'T work, it's about what he prefers. I guarantee you he can do his job with a knife with an 8 degree edge, he just doesn't like to.


I think it's an all too common fallacy to assume that being exceptionally experienced and skilled at something makes you the god of that thing, and your word becomes dogma. He is the guy to talk to about breaking down fish, but not about sharpening--al least not without finding out if he actually has any sharpening credentials. He's a butcher, not an engineer, after all, and people in trade jobs(even the top of trade jobs) often have a "whatever works" approach, and don't need to alter or experiment with a formula that is clearly working for them!

There are people in Japan and Seattle who don't waste an ounce of fish, and can dispatch tons of fish with effortless finesse--all while using cases of disposable knives. Breaking down fish like a pro is not about knife skills--it's about fish anatomy. If you have a good understanding of what an animal looks like inside and out, you can break it down with anything--my father slaughtered and butchered every animal we raised or shot growing up with a 4" Buck knife, and it never got sharpened.

iceman01
04-08-2011, 01:19 AM
I wasn't referring to the paper part (per Se) but that you tested between stones to feel the difference.

I just wanted to say that using the paper test, the sound and/or feel can be misleading. So you might assume that the knife you are testing is not sharp, although it is really sharp but has some bite.

Jay
04-08-2011, 10:32 AM
Bourdain worked Justo into a quickfire challenge for this season's Top Chef all stars. The contestants watched him break down fish, then it was their turn....

http://www.youtube.com/watch?v=BZarDNgM2Bo

http://eatocracy.cnn.com/2011/02/25/the-fish-butcher/

Thanks for the link!

Eamon Burke
04-08-2011, 02:51 PM
I just wanted to say that using the paper test, the sound and/or feel can be misleading. So you might assume that the knife you are testing is not sharp, although it is really sharp but has some bite.

Well, there are differences between different papers as well, and there is something to be said for technique of cutting paper. But the main reason to do it is a before-and-after of each step to analyze how it cuts.

evanjohnson
04-10-2011, 06:25 PM
Well, there are differences between different papers as well, and there is something to be said for technique of cutting paper. But the main reason to do it is a before-and-after of each step to analyze how it cuts.

Well, I've cut a lot of paper in my life but still can't figure out how to cook it.

SpikeC
04-10-2011, 06:44 PM
Well, I've cut a lot of paper in my life but still can't figure out how to cook it.

Low and slow???
:cook:

heirkb
04-10-2011, 07:12 PM
Pete, tomatoes like a toothy edge - true, but I also suspect that you're creating a multi-faceted bevel (through natural wobble) that when polished to 5k becomes somewhat rounded or convex thus slippery. You may see this work different on different knives that have different steels though, ie - finer grain may result in smoother edges when polished.

I'm not clear on why a convex bevel caused by a lot of wobbling would lead to slipperiness at the edge. Could someone please explain this to me? I ask because some of my knives have been a bit like this, too.

UglyJoe
04-10-2011, 07:17 PM
It's all about angle control. Wobble convex edges, but a lower grit stone leaves larger "teeth" in the edge that are big enough to overcome any rounding issues. The higher the grit, the smaller the teeth, and the more precise your edge must be. Otherwise you end up with a round, slippery edge. The same thing happens at the lower grits, but the teeth generated are big enough to overcome the very slight rounding off you might get from wobble.

heirkb
04-10-2011, 09:41 PM
Thanks, Joe. So the idea is that on a finer stone, wobbling causes you to remove the teeth at the edge, because they are smaller? This just means that I'll have to go slow and try my best to keep the angle steady on the higher grit stones, right?

Dave Martell
04-10-2011, 10:10 PM
You will wobble on both coarse and fine stones. Because coarse stones leave behind a rough edge the micro-teeth will cut even if you're bevel is rounded over whereas finer stones leave behind a smoothed over rounded edge which simply slides on or over many substances.

So the higher you go with grit levels the more steady you must be - BUT - this is also true for the coarsest stone (and every one thereafter) you use in the series because this is the foundation and subsequent refining stages that can also round over the bevel. If you're only careful on the polishing stones you will still have a rounded over polished edge. :)

Eamon Burke
04-10-2011, 11:40 PM
Solution to this ever-intensifying need for angle control?

Strop, strop, strop.:thumbsup:

NO ChoP!
04-11-2011, 12:52 AM
I just commented today elsewhere (ahemmm), that I liked a toothy knife for slicing proteins. Its gotta be sharp, but a silky smooth, highly polished laser doesn't slice crusty, charred, grilled meat well for me. Well, some didn't respond too well to this notion. I am glad to see I am not the only one who feels this. I often take my suji up the progression, and than I "strop" it with the 1k, lightly. It gives me that "bite" to tear through cooked meats....works well for me.