Home Cosmetic Science Talk Formulating Benzoic acid vs sorbic acid vs dehydroacetic acid vs salicylic acid antifungal

  • PhilGeis

    Member
    April 19, 2023 at 8:43 am

    Why? A pH limitation?

    • Abdullah

      Member
      April 19, 2023 at 9:53 am

      I just wanted to know which preservative is stronger and how much difference is in strength.

      There isn’t any pH limitation. The question about these preservatives is in acid form. For example sodium benzoate 0.3% at pH 4.18 and 1% at pH 4.95, both will have 1500ppm in acid form so what amount of sorbic acid or dehydroacetic acid in their acid form will have the same amount of power?

      1500ppm or less in acid form?

      As they have different pka, different amount of these will have 1500ppm in acid form at those ph. That is why i asked about the acid form, not actual amount.

  • PhilGeis

    Member
    April 19, 2023 at 10:07 am

    I’d not get too carried away with pKa - your formula may impact. Suggest 2500-3000 Na benzoate at favorable pH. Do not think sorbate/DHA buys anything more and brings in more question of stability.

  • Abdullah

    Member
    April 19, 2023 at 6:50 pm

    Thanks a lot

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