Preservatives for Small Batch Cosmetics (1 month shelf life)

Even for small batches of cosmetic formulas intended for use within approximately one month, it is generally recommended to include a preservative. This is because microbial contamination can occur from various sources during mixing, packaging, and use, regardless of the batch size or intended usage period. Factors such as the cleanliness of the preparation environment, the type of packaging used, the ingredients in the formula (especially natural ingredients which can be food for microbes), and storage conditions all play a role in the potential for microbial growth.

Since it's difficult to guarantee complete sterility and prevent contamination in a home mixing environment, adding a preservative acts as a safeguard to prevent the growth of bacteria, mold, and yeast that could spoil the product or potentially cause skin irritation or infection.

A mild option like Mild Preserved Eco™ is often recommended for this purpose. Mild Preserved Eco™ is a gentle ingredient that helps prevent spoilage in cosmetic formulas. It is not classified as a traditional preservative by the FDA, which allows formulas using it to be claimed as "preservative-free". It can be used at a rate of 1.0-1.5% in general cosmetic formulas.