Sorbic Acid Bon Conservateur No known benefits Sorbic Acid at a glance Preservative naturally derived from mountain ash berries Used to prevent the growth of bacteria, mold, and fungi In addition to cosmetics, it is also used to preserve foods Ruled safe as used in cosmetics Sorbic Acid description Sorbic acid is a preservative naturally derived from mountain ash (also known as rowan) berries or manufactured synthetically. Its name, sorbic acid, comes from the taxonomic name of mountain ash, _Sorbus aucuparia_. Sorbic acid is used to prevent the growth of bacteria, mold, and fungi. Its safety and effectiveness make it useful in a variety of products, including several foods, cosmetics, and even contact lens solutions. It tends to work best at an acidic pH of 4.5 or lower. In its raw form, sorbic acid is a white, crystalline powder. The independent Cosmetic Ingredient Review board has ruled sorbic acid safe as used up to 0.6% in cosmetics.