Do you make your lotions and creams with a phases process? This refers to all water ingredients heated in one pot and all oil ingredients heated in another pot.
If you do this you are using a technique called phases. Here at TheSage.com we teach how to make lotions by heating all ingredients together. We get more stable emulsions this way. If you are having difficulties with your lotions separating, or becoming curdled then omit the technique which is causing the problem.
Almost each time I hear of someone having trouble with lotions I find they use the phases method for heating and mixing. Phases are used to help very large manufacturing facilities heat and mix more economically, not because phases is the only method to make lotions.
If you MUST use phases (old habits die hard) then here are some things to remember:
Water ingredients: this includes water, water soluble humectants like glycerin and Hydrovance, and water soluble powders.
Oil ingredients: this includes fixed oils, butters, true waxes and oil soluble solids.
Where does the emulsifying wax go? In the water! But you say it is a wax, right? Nope. Emulsifying wax is a fatty alcohol and it looks like a wax. Treat it like the other water soluble items in your mixture.
When to add extracts, fragrance, essential oils, colors and preservatives? Wait on these products unless the manufacturer advises to add during heating. I wait until the mixture is about 120°F and add these items. I then stir well but I don’t use high-shear mixing at this stage – just gentle mixing.