Usage level .1%. Needs pH of product to be below 6 to be effective. A widely used food preservative, that is gaining popularity in natural cosmetic products. It is the natural potassium salt of sorbic acid, which when dissolved in water based products is effective against yeasts, molds and select bacteria. Should be used with other synergistic preservatives such as GSE or Sodium Benzoate to provide greater protection against micro-organisms.