Meat or meat products can be fresh, frozen or chilled. However, a large part of meat products are air-shipped fresh or chilled. They must be kept under cold conditions at all times during the whole distribution process.
One of the major reasons is that micro-organisms and enzymatic activity can significantly affect meat quality and safety as temperature increases. Results from such attacks are: initial colour changes, unpleasant odour and bad taste. In the worst cases, there is a possibility of food poisoning. To counter these effects, it is necessary to keep the meat at low and constant temperatures.
The preservation of meat and meat products is usually limited to a short time, since most mechanisms responsible for deterioration increase with time. In the case of air-shipment, a few important factors that may affect the shelf life should be monitored. Amongst them are the initial microbial load, temperature, integrity of the packaging and the species of animal transported.
The initial microbial load is important when storage temperature cannot be maintained properly. A small increase of a few degrees in temperature may result in growth of different types of micro-organisms responsible for spoilage. The optimum growth temperature range for most micro-organisms is between 15°C and 40°C. This shows how temperature control can be an effective means for keeping micro-organism activity low.
Most meat and meat products have a critical temperature where quality and safety can be greatly compromised. This critical temperature is usually 5°C. So a temperature range between -1°C to 3°C should be maintained at all times.