An antioxidant is an ingredient that keeps oils and fats from turning rancid. Three natural antioxidants are Vitamin E oil, lecithin, and wheatgerm oil (a natural source of vitamin E ). A preservative is an ingredient that kills, or inhibits, the growth of bacteria, mold, and/or fungi. Certain essential oils, such as tea tree oil, thyme, eucalyptus, rosemary, and peppermint, are effective at killing some types of microorganisms, and can be used as natural preservatives to some extent. Glycerine can also be used as a natural preservative in some water-based products.

Adding an antioxidant or a preservative to a cosmetic product doesn’t guarantee that it will last forever. (This is true for handmade cosmetics as well as mass-marketed department store cosmetics.) Antioxidants and preservatives are added to cosmetics to help them stay fresh until they are used up. The effectiveness of your chosen preservative, or preservation system, depends on many factors including the ingredients used in the cosmetic product, how much preservative is being used, how the cosmetic product was prepared, and how the cosmetic product is being stored (length of storage time, type of container, temperature, etc.). If a cosmetic recipe you like is having problems staying fresh, try adding a small amount of a preservative or antioxidant to it to see if that helps it to last longer. It may take some experimentation to get exactly what you want. With essential oils, tiny amounts (1%-2% of your recipe) should be used. With glycerine, much larger amounts (15% of the water phase of your recipe or more) are needed.

Shopping Links:
Antioxidants:
Vitamin E Acetate
Natural Vitamin E /Dl-Alpha Tocopherol
Wheat Germ Oil
Essential Oils:
Eucalyptus Oil
Peppermint Oil
Rosemary Oil
Tea Tree Oil

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