Acidic Foods vs Edge Retention?

Is it true that cutting acidic foods dulls your edge?
I think highly acidic or basic foods can "eat" into the metal at a very slow rate and scale, but can they actually dull your edge?

I ask this because I was thinking of forcing a patina on my carbon knives but am wary of the stuff I use to force it with eating away at my edge. I see people do it with mustard, coffee even hot vinegar! Wouldn't boiling liquids dull your edge too?

My work colleagues at the last restaurant I was in would cringe everytime they saw me cut lemons with my knives.. Yet I don't think I've noticed a difference..

Plus, what are you favorite patina methods? Forced or natural?
Mine had a natural but I polished it out after some microrust and I was wondering if a forced patina could be more consistent through the blade and even look a bit prettier.

Natural patina = healthy, natural glow.
Forced patina = spray tan.

btbyrd said:

Natural patina = healthy, natural glow.
Forced patina = spray tan.

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:rofl2: Good analogy

If cutting acidic food or forcing a patina affect the edge, simply touch up the edge.

Forced patinas can be attractive. Here's one I did on a Konosuke using mustard dabbed on with a fingertip:

My understanding is that cutting acidic foods will dull your edge quicker than non-acidic items as the acid causes micro pitting on the actual cutting edge itself as well as the rest of the blade. Patination, forced or otherwise, will help protect the knife as a whole but won't do much for the cutting edge as you will be removing the patina when you sharpen. And you will be sharpening more frequently if you are cutting acidic foods.

btbyrd said:

Natural patina = healthy, natural glow.
Forced patina = spray tan.

Click to expand...

🤣 I could not have provided a better response.

OliverNuther said:

My understanding is that cutting acidic foods will dull your edge quicker than non-acidic items as the acid causes micro pitting on the actual cutting edge itself as well as the rest of the blade. Patination, forced or otherwise, will help protect the knife as a whole but won't do much for the cutting edge as you will be removing the patina when you sharpen. And you will be sharpening more frequently if you are cutting acidic foods.

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Does this hold true for both stainless steels and carbon, or just carbon?

Interesting topic. I just experienced my first "patina" with a new petty knife that's HAP40 clad in stainless steel. The exposed HAP40 area below the cladding line is "semi-stainless" and does change color after exposure to tomatoes and lemon. I didn't like the initial effect that was kind of blotchy, so I cleaned it off and forced an overall patina with lemon juice. Now it's just a nice solid golden color on the exposed HAP40 part of the blade, and hasn't changed with further exposure to lemons, chicken, etc.

That HAP40 is really hard; something like HRc. 68. It's difficult to imagine it pitting with acid contact, but should I be worrying about this because it has that patina effect?

I've seen dulling to occur with very stainless as well. Leaving pizza (tomato)sauce on the edge overnight is no good idea. Clean the edge immediately, whether carbon or stainless. A patina will protect the faces, not the very edge. A high polish will protect a bit, though. A rough edge is vulnerable.

And about forcing a patina: nothing wrong with it. Dab with a cloth moisted in hot vinegar and clean the very edge immediately by cutting into a cork. Rinse with very hot water and wipe off rust. Repeat a few times until you've got a smooth surface.

Benuser said:

A high polish will protect a bit, though. A rough edge is vulnerable.

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Good point. Smooth finish always is better for corrosion resistance. Less surface area, less places to trap contaminants.
And less area for them to make contact and chemically interact.

Questions answered in order.
1. Yes from my personal experience* acidic foods full your carbon edges considerably. Probably most noticeable on Off the stone edges. From playing around I sharpened my carter to slice paper towel, then cut lemons (probably 10) using tip draws and noticed a serious difference in ability to cut paper towel.
2. Boiling liquids, yes from my experience* not like slicing lemons or tomatoes.
3. Favourite pritina methods is using mustard, but I would say only use if in professional enviroment and noticing the carbon is making food change colour or smell or taste.
Get a stone or two, lean to sharpen a little an you can do your own tests. For both polishing and sharpening and long term knife care.

Rinsing with hot water will enhance the patina formation, but indeed slightly dull the edge. A few passes on your finest stone -- or newspaper, or whatever -- will remediate.