What is preservation? When we speak as formulators about preservation, we are referring to the protection of our products from contamination by bacteria, yeast, or mold from the time the product is manufactured up until the time the product is completely used up by the consumer. A preservative is defined as a material that will prevent the growth of or react with and destroy microorganisms that might damage the product or create a health hazard by growing on or in the product. Unlike disinfectants and many antiseptics that must act quickly and powerfully, often against specific organisms, preservatives must act steadily and effectively against a wide range of microorganisms over a long period of time. Preservatives however are not a replacement for basic good housekeeping procedures. This does not mean that the types of products that we are concerned about here must all be manufactured under sterile conditions, but a reasonable level of cleanliness is dictated by "GMP's" (Good Manufacturing Procedures). In other words, the preservative is intended to keep a clean product free of incidental contamination, not kill the overwhelming number of microorganisms that can be introduced during manufacturing in an unclean plant. For more information, see “Principles of Preservation” in the TDF Library.