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  • mixing pH

    Posted by crillz on December 9, 2020 at 11:23 am

    Making a hydrating lotion and the pH came out at 3.5
    I understand I can raise the pH through Triethanalomine, Sodium Hydroxide or Arginine which I have just learnt. 
    I used citric acid as a chelating agent but understand it also can decrease the pH a small amount. Is it ok to keep citric acid in the product and up the pH with one of the above 3 ingredients or will that  just make them work against each other.

    For the sake of it ingredients were:
    Aqua                      67%
    Glycerin                  4%
    Xanthan Gum         0.5%
    Cetearyl Olivate Sorbitan Olivate (Olivem 1000) 4%
    Glyceryl Stearate     2%
    Cetyl Alcohol          2%
    Shea Butter             1.5%
    Macadamia Oil        4%
    caprylic capric triglyceride  5%
    Vitamin E                0.3%
    Glyceryl Caprylate/glyceryl undecylenate (plantaserv N) 1% 
    Lemon Lime Frag    0.3%
    Citric Acid               0.2%

    Also after watching the Preservatives webinar yesterday I think I will add a second preservative, both at half level.


    crillz replied 2 years, 12 months ago 2 Members · 3 Replies
  • 3 Replies
  • crillz

    December 9, 2020 at 12:12 pm

    Water is 75.2 percent sorry. Not 67.

  • ketchito

    December 9, 2020 at 12:52 pm

    @crillz Citric acid is a pH regulator rather than a chelator. Sodium citrate (which is the salt formed after neutralizing Citric acid with Sodium hydroxide) is a chelator, but for that you need to raise pH above 6.4 (so carboxylic groups are proton-free and can properly interact with metallic ions). 

    When you add an additional preservative, make it an antifungal since the system you’re using lacks of activity against mold and yeast. 

  • crillz

    December 9, 2020 at 10:00 pm

    Thanks ketchito, I thought citric acid did both. Will do with the preservative

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