Home Cosmetic Science Talk Formulating Benzyl alcohol and Phenoxyethanol as preservatives

  • Benzyl alcohol and Phenoxyethanol as preservatives

    Posted by labtechnician on April 3, 2014 at 7:32 pm

    Hi

    I want to use combination of Benzyl alcohol & Phenoxyethanol as preservatives for my new body lotion. Can any one tell me how much percentage of these preservatives should be used? When I should add these preservatives in formulation? should I add in water phase before heating or should I add in cool down phase? Comments will be really appreciated
    labtechnician replied 10 years, 2 months ago 3 Members · 4 Replies
  • 4 Replies
  • mikebavington

    Member
    April 3, 2014 at 8:17 pm
    Phenoxyethanol 

    used at approx. 0.5%-1%. Add at cool-down or at least below 100 degrees Celsius. Add to separate water phase (third phase) and then add to overall formula. 

  • labtechnician

    Member
    April 3, 2014 at 10:04 pm

    Thanks @mikebavington

    can anyone help with Benzyl Alcohol??

  • MakingSkincare

    Member
    April 4, 2014 at 5:50 am
    Info below (except last para) copied and pasted from http://makingskincare.com/preservatives/

    Phenoxyethanol is most active against Gram-negative bacteria.  It is used in combination with other preservatives, in part because its activity is weak against yeast and mold. 

    Benzyl alcohol is good to very good against Gram+ve, moderately poor against Gram-ve, poor versus fungi and moderately poor against yeast. Benzyl alcohol has low water solubility, is volatile (so should be used with an antioxidant) and may be inactivated by nonionic surfactants such as polysorbates. Note: over time (6 months) benzyl alcohol oxidises to benzaldehdye which smells quite strongly of almonds.  Add 0.3-0.5%. 

    You might consider adding another preservative to the mix to get broad spectrum coverage.  Also check that the preservatives you end up choosing work within your product’s pH as the organic acid preservatives need a low pH.

  • labtechnician

    Member
    April 8, 2014 at 6:25 pm

    Thanks @MakingSkincare for such a good information..

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