With few exceptions all foods lose quality and potential shelf life at some rate or
other following harvest slaughter or manufacture in a manner that is very
dependent on food type composition formulation (for manufactured foods),
packaging and storage conditions. Spoilage, or other changes that lead to loss of
shelf life, may occur at any of the many stages between the acquisition of raw
materials and the eventual consumption of a finished product.
The principal reactions that lead to spoilage, and that are consequently also the
Principal targets for effective preservation and control ,are well known, and
relatively few. They include some that are essentially physical, some that are
chemical. some that are enzymic and some that are microbiological (Huis in’t Veld,1996).
While most preservation techniques therefore aim to control all the forms of
spoilage that may occur, the overriding priority is always to minimize any growth
of micro-organisms.