Preservation is a very complex issue and those of us formulating in the "Natural" realm face challenges as the choice of preservatives are more limited and the preservative options are not as efficacious. Preservation is not as simple as adding 1% of a preservative to your formulation. You best think of it from the perspective of a "preservation systems" approach:
(1) Follow strict GMP: Simple things like always wearing gloves when formulating, wiping down all of your equipment and vessels with alcohol immediately before use.
Chemist/Microbiologist formulating in the Organic & Naturals & Clean Beauty arena under ECOCert/Natural Products Assn/Whole Foods/National Organic Program/Clean At Sephora/Credo Clean guidelines focused skincare & haircare products.
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