If you create a cream or lotion that contains a "water phase" (as opposed to a balm or salve consisting of just carrier oils, butters and waxes) then you MUST use a preservative to protect against bacteria and mold contamination. Even if you are creating just for your own or your family's use, if you plan to use the product for more than a few days and to store at room temperature, you are providing a buffet feast for invisible unfriendlies.
This point was driven home to me years ago when a professional client, the owner of a "Natural Skincare Products" company sent me some lovely samples of her various products. One sat on a shelf for a few weeks, perhaps a month. When I opened it...there were green things on the top. Now I know that contamination can take place invisibly, and that by the time we SEE evidence of mold or bacteria growth it has already gone on for some time.
I've queried several of my friends who supply various preservatives, asking which was the best for the "kitchen chemist"... the easiest to work with that will still give proven results, and the answer I came up with was OPTIPHEN™. Optiphen™ is oil based and will blend readily into the oil phase of a cream or lotion.
From the manufacturer: OPTIPHEN™ A safe and effective broad spectrum preservative for the
"kitchen chemist." Optiphen™ is a liquid preservative providing broad spectrum protection
against bacteria and yeasts
Paraben and formaldehyde free, Optiphen™ is effective for
emusions (creams and lotions) and anhydrous products such as balms and scrubs.
We recommend using Optiphen™ at 1% of your total formula, and adding after
creating your emulsion, while it is cooling down.
Optiphen™ is ISP’s first globally approved preservative and is an excellent
choice for formulations that require a paraben and formaldehyde-free
preservative system. Optiphen™ is a unique liquid preservative that consists of
phenoxyethanol in an emollient base. The combination of these ingredients
provides optimized protection against microbial growth from bacteria and yeast
while imparting a pleasant feel to the finished product. There are no Ph
requirements, and you will find it compatible with most raw materials. We
do not recommend the use of Optiphen™ in all water products, such as hydrosols
or herbal waters.INCI Name: Phenoxyethanol (and) Caprylyl Glycol
Recommended Use Levels: 0.5% - 1.5%
USAGE: After combining your water phase and oil phase, and stick blending until emulsified, add OPTIPHEN™ during the cool down phase, preferably at about 100F. Do not wait until the emulsion has cooled to room temperature; adding too late could break your emulsion.
You may also use OPTIPHEN™ in anhydrous products which may have water added during use, thus making them vulnerable to contamination as well, such as sugar scrubs.
For a selection of hand crafted cream and lotion formulas, we recommend Donna Maria Cole Johnson's "Making Aromatherapy Creams and Lotions" The one disagreement that I have had since this book was published was Donna Maria's treatment of preservatives as "optional" or "a matter of choice." Please, when following any of the formulas in this delightful book.. use the Optiphen™ at 0.5 10 1.5%. Keep your luxurious goodies SAFE as well as effective.