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  • Preservation combo

    Posted by fethtahir on August 29, 2022 at 10:41 am
    need help please.
    Can I use 0.3% Sodium Dehydroacetate to robust presevation system with 0.5% Phenoxhyetanol +ethyhexylglycerin (clariant)
    I make cold process water base toner and o/w. pH 4.5-5.0
    TIA….
    Abdullah replied 5 months, 1 week ago 3 Members · 6 Replies
  • 6 Replies
  • Abdullah

    Member
    August 30, 2022 at 1:59 pm

    pH 4 is easier to preserve than pH 5.

    If you have pH 4, more of it will be in acid form and it will not dissolve in water and will precipitate.

    What i want to say is, if 0.07% DHA in acid form can’t preserve your product, then add another anti fungal preservative with it. Increasing DHA won’t help. 

    Look at the commercial preservative blends that has DHA in it. There isn’t a blend that gives you more than 0.07% DHA in final product at maximum recommended use. 

  • fethtahir

    Member
    August 30, 2022 at 4:54 am

    Abdullah said:

    Whatever amount you add, some of it will be in acid form and some in salt form. Only in acid form it will function as preservative.
    Salt is more water soluble but not effective. Acid is effective but not water soluble more than 0.07%.
    If you add even 0.6% and it all dissolved in water, it means they are all in salt form and not effective. 

    noted, so the ph of the product should be 4.0 or bit higher will be okay? bcoz under 4 will be to acidic for daily use

  • Abdullah

    Member
    August 30, 2022 at 3:32 am

    Whatever amount you add, some of it will be in acid form and some in salt form. Only in acid form it will function as preservative.
    Salt is more water soluble but not effective. Acid is effective but not water soluble more than 0.07%.
    If you add even 0.6% and it all dissolved in water, it means they are all in salt form and not effective. 

  • fethtahir

    Member
    August 30, 2022 at 2:57 am

      btw the coa doc of DA said usage rate from 0.1-0.6. 0.07 is away lower than the recommended. any reason why I should add lower from the recommendation?

    Abdullah said:

    dehydroacetic acid is only 0.07% water soluble. I don’t know how much effective it would be.

  • Abdullah

    Member
    August 29, 2022 at 5:21 pm

    dehydroacetic acid is only 0.07% water soluble. I don’t know how much effective it would be.

  • fethtahir

    Member
    August 29, 2022 at 2:25 pm
    I use dehistilation water and yes i do add 0,2% phylate as chelator. or I must use EDTA?
    here is the formula

    48.5% Distlled water
    38.0% rose hydrosol
    4.0% sodium lactate
    0.4% lactic acid (ph adjuster)
    0.8% Phenoxhyetanol and Etylhexyl grlycerin
    3.0% extract
    0.5% dl phantenol
    1.0% propanadiol
    0.5% marine colagen
    0.3% rose eo
    1.0% alkamuls-CR40
    0.8% o-ethyl ascorbate acid
    1.0% Tranexamic Acid
    0.2% Sodium Phylate

  • PhilGeis

    Member
    August 29, 2022 at 11:03 am

    Should give your formula but prob. ok. 
    How good is your water?  Can you add a chelator, EDTA?