Choosing a preservative is one of the most important things you can do to produce a beautiful and safe homemade product. The first task is to determine if it requires one. If it doesn’t contain water – if it’s an anhydrous product composed entirely of oil soluble ingredients - and won’t be exposed to water, you don’t need a preservative. It’s a good idea to include an anti-oxidant like Vitamin E or rosemary oleo extract to extend the shelf life of your oils and butters, but you don’t need to worry about contaminants like bacteria, mold, or yeast because they need water to grow. Products like whipped butters, lotion bars, lip balms, salves, and other oil only products fall into this category.
How to Use Preservatives in Cosmetics Safely
How do you figure out how to use your chosen preservative? Some are heat sensitive, some are not, so the best suggestion is to ask your supplier for their recommendations. Liquid Germall Plus, Germaben II, Suttocide A, and Advance Aloe Leucidal go into the cool-down phase, while Phenonip, Cosmocil CQ, and Geogard Ultra are used in the heated phase. All preservatives come with a suggested usage range.
Liquid Germall Plus is used at 0.1% to 0.5%, Germaben II at up to 1%, Geogard Ultra at up to 2%, and Leucidal 2% to 4%. If you’re using a high percentage of proteins, botanicals, extracts, or hydrosols, consider using the upper range of the suggested usage rates as those ingredients can be hard to preserve.
Selecting the Right Preservative
One preservative does not fit all. For each product, you’ll have to consider a few things before finding one that works best, like the suggested pH ranges, oil quantity, charge, and ingredients.
Optiphen ND works best for products with a pH of 5 to (a very small pH range) and can be inactivated by proteins and cationic (positively charged) ingredients, which means it’s not a good choice for products in which you might use a cationic emulsifier like Incroquat BTMS-50 or Rita BTMS-225, like hair conditioners.
Optiphen and Optiphen Plus have the potential to destabilize emulsions, and it’s suggested that you add these preservatives in the cool-down phase at 45°C to 55°C and continue mixing until cooled to room temperature to prevent curdling. (I don't suggest these for beginners.)
Preserving your product well is about more than the preservatives. Consider the packaging you’re using with your products.
Frequently Asked Questions
Q: If I make a lotion that contains emulsifying wax soft and silky (from your company) which preservative should I use that won't be deactivated by emulsifying wax soft and silky ingredients?
A: Preservative - Water Soluble PF or Phenoxyethanol + CG might be worth testing in your recipe. The better choice will depend on your specific recipe, so test thoroughly.
Q: Hello! What would be recommended to preserve an
anhydrous lip scrub? From what I gather, an oil-only scrub doesn't need to be preserved, but I would feel more comfortable having one in a product for sale, especially if there's a chance for water to get mixed in. A lot of the ones I've looked at don't seem to be lip safe, though, so what's the solution?
A: Preservative - Phenonip is approved for lip products at 0.5%.
When crafting your own skincare and personal care products, it’s essential to know how many preservatives to use in cosmetics to ensure product safety and longevity. Using cosmetic preservatives, especially water-soluble preservatives for cosmetics, helps prevent microbial growth in formulations containing water. . For effective results, always refer to the recommended usage rate for your chosen preservative and test your final formulation for stability and safety.
Introduction to Preservatives in Cosmetics
Choosing a preservative is one of the most important things you can do to produce a beautiful and safe homemade product. The first task is to determine if it requires one. If it doesn’t contain water (if it’s an anhydrous product composed entirely of oil-soluble ingredients) and won’t be exposed to water, you don’t need a preservative.
It’s a good idea to include an antioxidant like
Vitamin E or rosemary oleo extract to extend the shelf life of your oils and butters, but you don’t need to worry about contaminants like bacteria, mold, or yeast because they need water to grow. Products like whipped butters, lotion bars, lip balms, salves, and other oil-only products fall into this category.
If you are making a product that contains water or might be exposed to water, then you definitely need a preservative. Lotions, scrubs, body washes, conditioners, toners, shampoos: all of these need some kind of preservative. Without one, you’ll see contamination in a short period of time, in as little as three days!
Understanding Water-Soluble Preservatives
When looking for a preservative, ideally you’ll choose a broad-spectrum preservative, one that battles all the beasties of contamination. Liquid Germall Plus, Germaben II, Phenonip, Geogard Ultra, Optiphen ND, Optiphen Plus, Suttocide A, liquid Leucidal, and Advanced Aloe Leucidal fall into this category.
If you choose a preservative that isn’t broad-spectrum, you’ll have to combine it with something else to ensure you get the greatest protection possible. Sodium benzoate, polyaminopropyl biguanide (Cosmocil CG), and Natrapres work well against bacteria, while sorbic acid and Liquipar oil are good fungal, mold, and yeast inhibitors. Check the suggested usage rate for each ingredient, then combine them to create a preservation system for your product.
If you're making natural products, you may wish to consider a preservative with an ECOcert designation, like Leucidal, Advanced Aloe Leucidal, and Natapres. These are all relatively new ingredients, and there are some concerns that they aren’t working as effectively as expected. If you choose to use one of these natural preservatives, use it at the maximum rate, and consider investing in preservation efficacy or challenge testing if you plan to sell.
