Adjusting Emulsion Viscosity
How to make your emulsion thicker or thinner.
First analyze your formula to see what ingredients are contributing to viscosity. This is usually the emulsifier blend, gums/polymers and any fatty alcohols/acids (stearic acid, cetyl alcohol, cetearyl alcohol) or waxes in your formula.
If you wish to make your emulsion thinner, all these ingredients listed above also provide stability so do be careful not to reduce the concentrations by too much if you are to avoid emulsion destabilisation. The following web page provides the information you need to calculate the minimum amounts of emulsifiers and stabilisers you need: http://makingskincare.com/emulsions-stability/
To reduce viscosity, you can also swap out your emulsifier blend for one which is thinner, such as TEGO® Care PBS6 or the pair up these single emulsifiers: TEGO® Care CG 90 with TEGO® Care PS.
Note: If your emulsion turns out much thinner than expected, bear in mind some ingredients can thin emulsions, such as urea or caprylyl glycol so you may wish to reduce the concentrations of those ingredients or add more thickener to compensate.
If you would like to make your product thicker and have only just made your emulsion, wait a couple of days before assessing the viscosity. If your emulsion is still thinner than you would like, adjust your next formula to increase the level of fatty alcohols/acid by 0.5-2%. This will also make your product slightly more heavy, draggy and creamy. If you wish to avoid this you add a water phase gelling agent, such as 0.5%-1.5% sclerotium gum or siligel™ instead.
6 thoughts on “Adjusting Emulsion Viscosity”
I am experimenting with body butters and would like to add coffee grounds and powders… I have tried adding them in the oil phase but I’m looking for a colour and smell change… also would the addition of these(I can change percentages so they still add to a hundred) affect product stability/efficiency?
Hi Carole, it would depend on the formula. Please do post your formula in % in the facebook group.
After reading some of your articles about emulsions and thickening, i was wondering if it’s possible to thicken an emulsion after emulsification has occurred? Say, the batch comes out too thin and it hasn’t thickened up after leaving it for a few days. Is there any way to “save” a batch without having to start over?
Hi Sophie, you might be able to depending on the formula. If you do not have electrolytes in your formula you can add 1% sepigel 305 straight in: https://www.makeyourown.buzz/cc-sepgel-305/ (Electrolytes could be in the form of ingredients which start with the words “sodium”, “potassium” and aloe and some extracts could also be electrolytes).
Hi my formula For my leave in spray is no longer emulsifying. The cream floats to the top. I use BTMS-50. Thats all i been using and it’s been fine. No Idk what’s happening. I tried making a 6L batch a 4L batch then a 24oz batch and the all have separated from the water phase and became creamy. What am i doing wrong? How do i fix this?
without knowing your formula in % it is hard to advise. Do go through the steps here