So I just heard about putting a carrot in the deep fryer so as to pick up the burnt junk and keep the oil clean for longer. I tried it. It works! Now I'm wondering how it works, and what other veggies or whatnot can be substituted in place of the carrot?

  • 2
    Could you possibly share some more information about the trick and how you went about it? Did you put the carrot in heated oil or cold for instance? Jan 7, 2015 at 13:07
  • @Richard I put it in after the oil heated up, right before I started lowering food in the basket. I was extremely sceptical but figured it couldn't hurt to try. What happened was is the carrot turned blacker and blacker with each batch and shriveled up. I told showed it to the kids and told them it was a hot dog. They fell for it:)
    – user6591
    Jan 7, 2015 at 13:49
  • 4
    Poor carrot. Your sacrifice shall not be forgotten. Jan 9, 2015 at 18:52
  • 1
    @user, I'd really like to find out where you heard this. I can't find reference online and I am a pretty good googler
    – Escoce
    Feb 25, 2015 at 17:42
  • 2
    @Angrycook I'm not sure how this could possibly damage your fryer. Please explain.
    – Catija
    Apr 8, 2017 at 17:32

3 Answers 3


As to the science behind why this works, I can only guess.

However, as to other things you can try for this trick, I managed to find some references from old cookbooks about using slices of potato for clarifying their deep-fryer oil. Other suggestions were a slice of bread or lemon peel. Weird — but interesting.

The Young Woman's Journal, Volume 12 (1901)

Mrs. De Graf's Cook Book (1922)

Olive Oil: From Tree to Table (2007)

When you have finished frying, clarify the oil by frying a piece of bread, a strip of lemon peel, or a slice of potato in it.

  • Potato made me think of something else that might be related : cooking.stackexchange.com/q/12378/67 . (related how, I have no clue, as these are both processes we don't understand)
    – Joe
    Jan 12, 2015 at 19:53

I am wondering if the mechanic behind this is the same as that used to clarify wine in the winemaking process. Some wines have a predilection to get cloudy with colloidal material, or just tiny particulates held in suspension. If a wine does not clarify on its own through gravity/sedimentatin, you can add ingredients to it that will by one mechanic or another join with the particals, and allow them to fall out of solution. Some of these reactions are ionic, some are absorbative, some just are gunky and sticky to the particles.

Examples are a clay from wyoming, I can't remember the exact name. egg yolk issinglass (it comes from fish guts)

I wonder if the potato and carrot have something that binds to the particles in the oil in a similar fashion.

  • 1
    For the most part, you have 3 modes of settling : "type 1" is affected by gravity, "type 2" is where particles flocculate (collect together) until they're heavy enough to be affected by gravity, and the others ("type 3" and "type 4") are hindered (eg, inter-particle forces like ionic charge) which keep it from settling quickly. In some cases, you add alum enough alum to the water to basically force everything to the bottom. But in all of these, you're dealing with something that spreads through the liquid, not just adding a solid item.
    – Joe
    Oct 13, 2018 at 23:10

I'm not sure where you got the idea, but it most likely does not work at all - the carrot does not clean the oil, the sugars in it are just getting caramelized by the heat, so the carrot gets darker and darker because it gets burned.

I suspect it can even be the reason why the oil was getting darker towards the end. If this trick worked, everyone would be using it for decades by now (especially fast food chains).

There are other techniques which seem to work, such as the gelatin technique.

  • 1
    Try it first. Then comment.
    – user6591
    Oct 15, 2018 at 15:56
  • @user6591 I don't really deep fry stuff that often, so I don't really have dirty oil at my disposal right now. But I have a different proposition - put the carrot in clean oil and see what happens - if the result is the same as with the dirty oil, it means something else is happening.
    – JohnEye
    Oct 15, 2018 at 16:04

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.