Meat preservation – principally concerned with the application of measures to delay meat spoilage which are caused by municipal chemical and physical changes.
Three general principles of meat preservation:
1. Prevention of microbial growth
- Exposing meat to high or low temperature
- Treatment of meat with substances e.g. salt, nitrite, other chemical preservatives which will kill microorganisms or delay microbial action.
2. Prevention of oxidation and/or rancidity
- Prevent too much exposure to light and air
- Addition of antioxidants like butylated hydroxyl toluene [BHT] or butylated hydroxyl anisole [BHA]
3. Prevention of enzymatic reaction by exposure to high or low temperature.
Methods of Meat Preservation:
1. Drying – removal of moisture from meat from its original water content [70%] to about 15%.
Two ways of drying:
- Natural – use of natural sunlight to reduce the moisture content of meat.
- Artificial – use of a chamber equipped with heating elements maintained at a temperature of 110°F – 120° F [43°C- 49°C] and relative humidity of 85% is used for drying.
2. Smoking – process of subjecting meat to the action of smoke and heat generated by burning hard wood and/or saw dust.
3. Salting – is a simple method of dehydration in which the salt causes the withdrawal of water from the tissue of both meat and spoilage organisms.
4. Curing – is the application of salt, sugar, nitrite [potassium or sodium nitrite] and other preservatives and adjuncts.
Three  ways of curing:
- Dry cure method – application of curing ingredients in dry form.
- Sweet pickle cure – ingredients are dissolved in water to make up the sweet pickle solution.
- Combination – could be done wither by combination injection with sweet pickle and soaking in curing brine or injection of pickle and application of dry cure.
5. Refrigeration – exposure of meat to the range of 36° to 50°F [2°C-10°C] to retard mold and bacterial growth for a limited period only.
6. Freezing – exposure of meat to a temperature range of 0°F to 32° F [-18°C-0°C] resulting to crystallization of the water in the tissues, thus, inactivating the enzymes and the bacteria present.
7. Canning – the hermetic or air tight sealing of food in cans or jars and heating under pressure [pressure cooker, retort, autoclave] to reach temperature above 100°C at specific period of time.
8. Freeze-drying- removal of moisture from the tissues by sublimation or the transformation of the moisture content into gas without passing the liquid state.
9. Irradiation – transfer of extremely large amount of energy to effect very rapid and selective biological and chemical changes in meat.