The causes of the loss of adequate qualities may be physical damage, chemical reactions, insect and rodent infestation and microbial growth. Spoilage is said to be a state of a particular food in which it is offensive to consumers' senses, usually caused by metabolites of contaminant microorganisms.
*Preslaughter handling of livestock and post-slaughter handling of meat play an important part in deterioration of meat quality. The glycogen content of animal muscles is reduced when the animal is exposed to pre-slaughter stress which changes the pH of the meat, to higher or lower levels, depending on the production level of lactic acid.
Higher levels of pH (6.4-6.8) result in Dark, Firm and Dry (DFD) meat. Long term stress causes DFD meat which has a shorter shelf life.
*Bacteria associated with meat spoilage produce unattractive odors and flavors, discoloration, gas and slime. Meat and meat products provide excellent growth media for a variety of microflora (bacteria, yeasts and molds) some of which are pathogens. The intestinal tract and the skin of the animal are the main sources of these microorganisms.
*Non-bacterial contamination plays an important role in hygienic properties of meat. Non-bacterial contamination includes chemical residues such as antibiotics, pesticides, hormones, heavy metals, radioactive fallout etc. meat may also be contaminated by grit, stones, pieces of metal glass, various inks, hair, paints, rust flakes, grease, wrapper etc.
Spoilage of meat
