Remel™ HC Agar

Cultivate and enumerate molds in cosmetic products using Thermo Scientific™ Remel™ HC Agar Base (Dehydrated) supplemented with polysorbate 80. HC Agar is prepared by addition of polysorbate 80 to HC Agar base. In 1986, Mead and O'Neill described HC Agar for enumerating molds in cosmetic products¹. Polysorbate 80 is used to neutralize residual amounts of preservatives and sequesters surfactants that may be present in the sample.

Cosmetics do not need to be sterile, but they must be adequately preserved. Microbial contamination to cosmetics is a substantial risk to product quality, regulatory compliance and consumer health². HC Agar Base, formulated by Mead and ONeill, is used for enumerating molds in cosmetic products¹. This medium differs from the traditionally used media for testing cosmetics products by addition of Polysorbate 80 and incubation time of 3 days, rather than 7 days, at 27°C ± 0.5°C to obtain a significant mold count³.

• Selective medium - Chloramphenicol inhibits bacteria, including Pseudomonas aeruginosa and Serratia marcescens, that are potential contaminants of cosmetic products.

The medium contains casein and meat peptones that supply essential amino acids, peptides, and nutrients necessary for microbial growth. Dextrose is the source of carbohydrate energy. Yeast extract supplies B-complex vitamins as well as serves as a growth enhancer. Essential ions are provided by ammonium chloride and magnesium sulfate. Sodium carbonate inactivates low levels of preservatives. Chloramphenicol inhibits bacteria, including Pseudomonas aeruginosa and Serratia marcescens.