Home Cosmetic Science Talk Formulating questions about xanthan gum

  • questions about xanthan gum

    Posted by HYB_88 on November 9, 2023 at 2:19 am

    Hi all,

    I’ve been trying to add 0.1 - 0.5% xanthan gum to my face cream formulation to help to stabilise it. I’ve been reading that it was generally recommended to disperse the xanthan gum in the oil phase prior to adding it to the water phase and homogenising it together. I’ve tried this, but I find that it is challenging to get all the xanthan gum into the water phase because a lot of it still sticks to the side of the beaker as it is poured out. It also settles very quickly in the oil phase, so even in the short period where I stopped mixing and heating I got some settling at the bottom of my beaker. I’m mostly doing R&D formulation work, so I am preparing small batches in beakers. I am guessing I am missing something here. Could you help to guide me on this please?

    Thank you so much!

    evchem2 replied 8 months, 2 weeks ago 4 Members · 9 Replies
  • 9 Replies
  • fareloz

    Member
    November 9, 2023 at 3:12 am

    Can you change the order and pour water phase into oil phase instead? Then you don’t have to scrape xanthan gum.

    • HYB_88

      Member
      November 9, 2023 at 3:36 am

      I thought about this, but I have an impression that I read somewhere that to make an O/W emulsion the oil should be added to the water phase? Is it ok to do it the other way around and still make an O/W emulsion please? I am very inexperienced in formulating still and appreciate all the guidance I can get. Sincerest thanks for helping!

      • fareloz

        Member
        November 9, 2023 at 8:23 am

        This is false. This rumor comes from the name oil-in-water (and some people think that oil-in-water == oil-to-water). In reality the emulsion you get depends on emulsifier you use.

        • HYB_88

          Member
          November 9, 2023 at 7:07 pm

          Thank you so much! This gives me a lot of clarity and is very helpful.

  • evchem2

    Member
    November 9, 2023 at 7:13 am

    If you have any kind of glycols in your formulation (glycerin, propanediol, etc), you can premix the xanthan gum in that instead (at least a 3:1 ratio glycol: gum is advised) and add that into the water phase instead.

    • HYB_88

      Member
      November 9, 2023 at 7:21 pm

      Thank you! I have butylene glycol in my formulation, but only at 1%. I tried to make the slurry. My steps were….measured out the xanthan gum into a beaker, added the butylene glycol to it, mixed it with a spatula to form the slurry (it turned out very thick and because of the low amount of the butylene glycol, I wasn’t sure if it was well-dispersed or not). Then I measured in the water, and then started to heat and mix with stirring. The photo below shows the result after heating…it turned out quite goopy, which I suppose is expected, but I’m concerned I’m not doing it right because I have no idea what to expect. I observed some clumping, and also a lot of air bubbles. Am I doing the steps right? Is there any other info that I can help to provide to make the troubleshooting better please? What can I improve on? Sincerest thanks for the guidance!

  • chemicalmatt

    Member
    November 9, 2023 at 7:55 am

    Disperse directly into water at room temperature while mixing with a baffled turbine (Lightnin’) mixer or a paddle blade while heating. The thixotropic shear thinning nature of xanthan and other polysaccharide gums is such that if you only apply shear in the locus of the mixer blade, the surrounding solution never gets mixing motion so you need to move the entire solution to fully hydrate. This holds true for nearly all gum resins and polymers. Honestly in over 35 years I never understood nor have I needed that “pre-mix in oils or glycol” approach. Gums need water and shear to hydrate. Period.

    • HYB_88

      Member
      November 9, 2023 at 7:27 pm

      Thank you so much! This is very insightful. I’ll give this a go.

  • evchem2

    Member
    November 10, 2023 at 7:08 am

    If you have only 1% glycol, I would stick to using <0.3% xanthan gum if you keep the slurry method- but if you’re seeing clumping then something isn’t working with the current process. The ‘gloopiness’ is characteristic of this gum, certain grades from specific suppliers can offer some improvement on that. Air bubbles are also normal, xanthan provides viscosity and suspension- to limit their incorporation try to keep your mixing blade a bit off-center and monitor your mixing speed (watch if you are pulling air into the vortex).

    ChemicalMatt’s method will also work, I recommend slurry method when I don’t know the processing equipment capability. The end goal is uniform product not just within one batch but lot to lot, and if your slurry is thick and difficult to incorporate on small scale it might also be an issue for scale-up, so use whatever method gives you best results.

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