Home Cosmetic Science Talk Formulating Creams breaking/curdling in the cooling phase

  • Creams breaking/curdling in the cooling phase

    Posted by AleH on May 3, 2020 at 8:48 pm

     

    Hi, I´m having
    problems in the cooling phase with these formulas. I was trying to make new
    formulas with Glyceryl Stearate Citrate, the first one (A) was ok, but I wanted
    it to be more consistant so I added some GMS (B) and it curdled when cooling,
    either I added the water phase to the oily phase or viceversa. Then I tried
    percentages suggested by Evonik in a formulation (C) and the same happened… I
    need some advice because I can’t find enough information on what I’m doing
    wrong, GMS? pH? Process? Thanks!

    Phase

    INCI

    A

    B

    C

    a

    water

    q.s.to 100

    q.s.to 100

    q.s.to 100

    a

    xantham gum

    0,4

    0,4

    0,4

    a

    glycerin

    5

    5

    5

    b

    Butyrospermum
    Parkii (Shea) Butter

    6,5

    6,5

    6,5

    b

    Cetearyl
    Alcohol

    6,5

    5

    2,25

    b

    Glyceryl
    Stearate Citrate

    4

    4

    1,5

    b

    Glyceryl Monostearate SE

    0,75

    2

    b

    Helianthus
    annuus Oil

    8

    8

    8

    ggpetrov replied 4 years, 2 months ago 4 Members · 7 Replies
  • 7 Replies
  • belassi

    Member
    May 3, 2020 at 9:07 pm

    To begin with, the GSC % is too high. Typical usage is 1.5-2.5%. I also think the glycerin content is too high, I would reduce it to 3%. 
    Cetearyl isn’t a primary emulsifier, it is a co-emulsifier and its efficiency at that job varies depending on the proportion of stearyl alcohol in your particular batch. Glyceryl monostearate is an effective emulsifier with an HLB of 5.8 and your GSC has an HLB of 12 which is radically different.
    Consider the result if you mixed an equal amount. You’d get an HLB of 9. Shea has an HLB of 8. By implication, you’d want to use a little more than half of the monostearate, I am not doing the Math for you but it might be around 60/40.
    The sunflower oil has an HLB of 7, so you will have to calc the average of the lipids and then use an appropriate ratio of emulsifiers.
    Get rid of the cetearyl to begin with (it has a very high HLB) and work with the other two.
    You have 14.5% lipids so begin with say 5% of the combined emulsifier and test without the gum. If it is not stable increase the % of the combo emulsifier. When it is stable, add the gum which will provide a safety margin. But 0.4% seems high. Try 0.2%. And it must NOT be the cationic version.
    Also consider the possibility of a process fail. Are you using enough shear?

  • EVchem

    Member
    May 4, 2020 at 10:55 am

    Good points already made- what is your final pH? GMS SE is anionic and works better for higher pH

  • AleH

    Member
    May 4, 2020 at 4:13 pm

    Thanks @Belassi! Trying to modify and exploring the
    sensorial and ingredient combinations I almost forgot the basics! I will keep
    on trying combinations following your advice!

    Regarding shear, I’m confused because in the Evonik formula says to add the oil
    phase to the water phase without stirring, and then homogenize, I was doing
    that very slowly.

    What I was trying is to find a less expensive cream,  I made one with  Cetearyl Olivate, Sorbitan Olivate (Olivem 1000)
    and GMS but it’s quite expensive and when lowering pH from around 8 (initial)
    to 5 it gets hard and curdles after few days. If I go below 5, let’s say 4, it
    losses consistency. It is dependant on GMS % I assume because of its anionic nature,
    should I stay higher than pH 5,5?. In this one, I think HLB is not the problem

    Phase

    Ingredient (INCI name)

    Quantity (%)

    A

    Aqua

    66,00

    A

    Xanthan Gum

    0,20

    A

    Glycerin

    4,00

    B

    Butyrospermum
    Parkii (Shea) Butter

    6,00

    B

    Cetearyl
    Olivate, Sorbitan Olivate

    8,00

    B

    Glyceryl Monostearate

    1,25

    B

    Persea Gratissima (Avocado) Oil

    3,00

    B

    Rosa rubiginosa (seed) extract

    2,00

    B

    Simmondsia
    Chinensis Seed Oil

    2,50

    C

    Aloe Barbadensis Leaf Juice

    0,05

    C

    Leuconostoc / Radish Root Ferment Filtrate, Aqua

    4,00

    C

    Sambucus nigra Fruit Extract

    2,00

    C

    Essential Oils

    1,00

    E

    Lactic acid

    q.s.

     

    Is the process the problem? I’m struggling with GMS! I read an article saying that high shear with GMS would make less stable the formula
    because it prevents the formation of the lamellar structure (Internal and
    External Factors affecting the Stability of Glycerol Monostearate Structured
    Emulsions. Wang et al,  RSC Adv., 2015,
    5, 93108)

  • belassi

    Member
    May 4, 2020 at 4:47 pm

    I use GMS in pretty much all my creams and have never had the slightest problem. I use high shear. I normally set the pH to 6.0

  • ggpetrov

    Member
    May 4, 2020 at 4:55 pm

    I use GMS SE in my lotions and have to say that it’s fantastic coemulsifier. It’s anionic by nature, so it benefits the main emulsifier and makes the emulsion more thick and stable. I have a recipe that is combination between Olivem 1000 and GMS SE and would say that is one of my favourite formulas. I always put Olivem at the hot water phase, and GMS SE at the fat phase. 8% of Olivem is way too high. Also the amount of the butter is too high for me. In most cases the amount of Olivem which I use in general is not more than 3%, and the amount of the GMS SE is not more than 2%. Just keep in mind that the GMS SE is an emulsion thickener, so you need to reduse the amount of butters at all. Also I process my emulsions with Dynamix homogenizer which is high speed shear process, but my emulsions are stable even after an year.

  • AleH

    Member
    May 5, 2020 at 6:52 pm

    Thanks, @Belassi and @ggpetrov I’ll keep on trying combinations following your advice!
    Just a question @ggpetrov, why should I reduce butter content when using an emulsion thickener like GMS? I’m trying to get a thick cream base than can be absorbed easily, wouldn’t the wax help (not for the absorption but for consistency)?

  • ggpetrov

    Member
    May 5, 2020 at 7:55 pm

    Well, that’s a question of personal taste. Me personally prefer to make a lotion like emulsions, because I am concerned about the safety of the products. Basically I use airless dispensers, so me and my clients are not able to touch the whole emulsion with the fingers. I noticed that the GMS SE is able to thicken the emulsion too much, so I carefully dose it’s amount. I don’t know, but I think that too much consistency modificators could make the emulsions hard to absorb. I guess it’s a question of tryouts to get the proper proportion.

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