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Home Cosmetic Science Talk Formulating Preservative

  • Preservative

    Posted by braveheart on February 12, 2015 at 6:24 pm
    I am about to test this combination as a preservative for a body cream: 
    Potassium Sorbate 1%
    Xylitol 1%
    Farnesol 0.5%
    Phytic acid (IP6) 0.3%
    Clove Oil (Eugenia Caryophyllus) 0.2%
    What do you think or suggest?
    braveheart replied 8 years, 1 month ago 5 Members · 11 Replies
  • 11 Replies
  • Belassi

    February 12, 2015 at 11:37 pm

    You’re in unknown territory. You will have to challenge test it repeatedly until it fails.

  • MarkBroussard

    Professional Chemist / Formulator
    February 12, 2015 at 11:43 pm

    That’s a relatively high percentage of Potassium Sorbate which can be a skin irritant and cause a flushing reaction in some people.  I would recommend that you make a batch at 1% and test it on yourself and few people.  

  • braveheart

    February 13, 2015 at 3:06 am

    Thanks for the suggestions.

  • braveheart

    February 13, 2015 at 3:12 am

    Actually, I am trying to create an alternative to this Ecocert preservative:

    Benzyl Alcohol, Salicylic Acid, Glycerine, Sorbic Acid, which is a broad spectrum.
  • Belassi

    February 13, 2015 at 3:16 am

    Glycerine isn’t a preservative.

  • Lara

    February 13, 2015 at 5:21 am

    Ive read recently that glycerin is a preservative enhancer as it is a glycol. Is this right?

  • Belassi

    February 13, 2015 at 6:58 am

    Some would like to believe that. I don’t. Pretty dubious using salicylic acid too, it is regarded as a therapeutic i.e. anti-acne etc. I would have thought. There are perfectly effective preservatives available that qualify as entitrely natural under European regulations.

  • Bill_Toge

    Professional Chemist / Formulator
    February 13, 2015 at 8:02 am

    @Lara, glycerine is a 1,2,3-triol rather than a glycol, and as @Belassi said, it is not antimicrobial in itself; however, it can be used to reduce the available water and hinder microbial growth

    (the catch: you have to use it at 40-50% w/w or higher for it to have any significant effect)
    on the other hand, 1,2-diols (propylene, pentylene, caprylyl glycol etc.) DO show some antimicrobial activity, which increases with the length of the carbon chain
  • braveheart

    February 13, 2015 at 8:28 am

    I found it here

    I think the actual actives in it are the benzyl alcohol and sorbic acid.

  • MarkBroussard

    Professional Chemist / Formulator
    February 13, 2015 at 12:50 pm

    Benzyl Alcohol, Sorbic Acid and Salicylic Acid all have antimicrobial effects.

    If you want to make your own preservative alternative to this you might try:
    Benzyl Alchol, Ethylhexylglycerin, Willow Bark Extract and Sodium Levulinate in 1,3-Propanediol.
    But, why take a chance making you’re own unproven preservative combination to begin with? …. scratching head.
  • braveheart

    February 13, 2015 at 2:51 pm

    I think it became an obsession after over-ordered potassium sorbate and xylitol and not wanting them to waste. 

    I guess I should just let it go!