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Speculation of FDA research projected results, Ph in food processing

  1. Nov 25, 2012 #1
    Hi Everyone,

    First of all, I'm not a scientist ;)

    But I'm doing some experimentation and just want to confirm if I am on the right track.

    FDA pickle recipe for non fermented pickles has the following parameters:

    50% vinegar
    50% water

    I am using standard commercial 5% distilled white vinegar

    - My water/vinegar combined pH is 2.8
    - According to FDA cucumbers have a pH of 5.1-5.7

    1. So pH of 5.1 cucumbers + 2.8 pH brine = 7.9/2 = pH 3.95
    2. So pH of 5.7 cucumbers + 2.8 pH brine = 8.5/2 = pH 4.25

    Now that the FDA takes for granted that the public might use inaccurate pH meters with an inaccuracy of ±.2 pH.

    The safe pH for food processing in a water bath caner is 4.6


    This recipe will result in a food product with a pH of 3.75 to 4.45, making this recipe fool proof.
  2. jcsd
  3. Nov 25, 2012 #2


    User Avatar

    Staff: Mentor

    You can safely assume pH of the mixture is never average of pHs of the mixed solutions.

    That is, you can design such solutions, but that's not how the pH works in general.
  4. Nov 25, 2012 #3

    what if I design the recipe to the same pH as FDA recommendations but substitute the acid for lemon juice, but match the pH of 2.8

    Then mix the cucumbers in the blender with the brine and take the pH.

    Would that be an indication that I am on the right track?

    Isn't the pH of the blended ingredients + recommended acidic brine solution enough to make the recipe safe?
  5. Nov 25, 2012 #4


    User Avatar

    Staff: Mentor

    Sorry, but I have no idea what is your problem. I have never heard about anyone using pH for pickling cucumbers :surprised
  6. Nov 25, 2012 #5
    Hi Borek,

    Problem is that the pH needs to be under 4.6 for food processing, getting calculations wrong could cause botulism and be fatal ;)
  7. Nov 25, 2012 #6
    It's a pretty long story I guess...

    I'm starting a food processing business in Thailand, FDA recommendations make food that taste bitter and to acidic.

    They overkill the recommendations, unlike in Europe where standards are more relax.

    So I'm trying to develop my own recipes safely, and then get them approved by Thai FDA.
  8. Nov 26, 2012 #7


    User Avatar

    Staff: Mentor

    I am afraid in such a case pH calculation is a nightmare. It will be much easier to determine required amount of acid experimentally.
  9. Nov 27, 2012 #8
    Hi Borek,

    Too bad I just registered yesterday...by looking at your signature I could have bought a meter from you ;)

    Just bought a ph 80 HM Digital but not accurate enough at .2 accurancy, so returned it and expecting the pH 200 at .02 , I hope they are good meters? Customer service is very good.

    I did some testing in the blender and my predictions are right on the spot.

    FDA recipes are overkill safe, so now I can calculate the pH before the recipes and then test in the blender to confirm, most are below 4.0 so it will be fine.

  10. Nov 27, 2012 #9


    User Avatar

    Staff: Mentor

    I am not selling pH meters.

    I would not believe in 0.02 accuracy - while it can be displayed, I would not trust the last digit.
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