The methods contributing to the prevention or retardation of microbial, enzymatic or oxidative spoilage and thus to the extension of shelf life. Index all methods for which information is available, even if a corresponding descriptor has already been used in *H. TREATMENT APPLIED*. Preservation descriptors refer to the finished food as a whole with these exceptions: (1) if the components of a multi-component food, such as cream pie, are preservation by different methods, index all methods; (2) if chemical preservatives are declared on the label, always index them even if it is known that the preservative was introduced through or is only present in a component or ingredient of the food; and (3) if the preservation method for an ingredient is declared on the label (such as brie cheese made from pasteurized milk) index it. Also use *INGREDIENT preservation by THERMAL PROCESSING* or *INGREDIENT preservation by IRRADIATION* when ingredients have been pasteurized, ultrapasteurized, sterilized or irradiated.