Commercial freezing extends the usable storage time for frozen foods since these comm. units freeze from 0F to -10F. The majority of moderately-priced residential freezers (refrigerator/freezer combos) freeze at 30F. Freezing at 0F or below allows for indefinite storage. In anything above 0F, frozen foods will continually break down (not counting freezer burn) until the 1. nutrients have all broken down and, 2. cell structures collapse from slow bacterial metabolization. Check the .gov site for guidelines listed by food-types (USDA and a few thousand food/cooking sites carry these guidelines). The longevity of most known foods can be found.
