The Sodium Benzoate/Potassium Sorbate preservative blend is a gentle yet effective solution for preserving all types of personal care products. This water-soluble combination of organic salts helps maintain product freshness by protecting against bacteria and mold. Benzoic and sorbic acids work together to prevent microbial growth and spore formation. Delivered as a convenient aqueous solution, this blend ensures easy handling and seamless incorporation into your final formulation.
This preservative blend offers high stability up to 80 °C and good compatibility with anionic and nonionic surfactants but is effective only within an acidic pH range. For optimal performance, it should be added to the aqueous phase during the early stages of formulation, with the final pH adjusted to below 5. For deeper technical insight into how organic acids preserve formulations, click here. Because the blend contains potassium sorbate, it may be prone to discoloration. This is a natural oxidation process involving the double bonds in sorbic acid and can be accelerated by various factors. The material should be discarded if a brown color begins to develop.
Approved in the EU for use at concentrations of up to 1.6% in leave-on products and up to 4% in rinse-off formulations, this preservative blend generally performs effectively at lower levels. As with most preservatives, it is highly recommended to let the finished product rest for 48 hours to ensure complete elimination of any microbial contaminants.
