Slaughter operations are not considered as complete until the carcass or meat leaves the premises for consignment to markets. Traditionally in many developing areas, meat is preferred warm, in the freshly slaughtered state; hence it is delivered to markets soon after inspection. By choice, therefore, slaughter premises have no need for cold storage and are thus not provided for in the design. Butchers hence tailor their supplies to the daily needs of the community and surpluses hardly occur.
Despite the fact that meat is sold fresh in these countries, cooling of carcasses is necessary before conveyance to markets. Freshly slaughtered carcasses, it must be remembered, are warm systems with temperatures close to ordinary body temperatures of 37°C (or 98.6°F) and subject to bacterial attack. They should be cooled rapidly under natural ventilation on the hoist in a well-spaced position until the surface is dry. Where refrigeration is available the cooling should reach a temperature of about 10°C (or 50°F). If it goes below this point, the carcass might “sweat” on the surface when conveyed outside, and this could cause bacterial growth. In the absence of refrigeration on the premises, commercial facilities can be used.
Refrigerated storage is absolutely necessary if shipment is to be delayed for a day or so. Sheep and goat carcasses are cooled to a temperature between -2° and +2°C (or approx. 28 to 35°F) for a period of 18 to 24 hours. Moving cold air causes rapid action, not only against surface spoilage but also deterioration in deep tissues. After cooling the carcasses must be consigned promptly in refrigerated vans.
Holding of meat for rationing purposes or against a lean season which is fast becoming a practice in some large urban centres in meat deficient countries calls for extended storage or freezing. Again rapid action is needed. The carcasses can be frozen whole or cut transversely along the last rib into two and packed in a way to allow free air movement around them. It should be noted that slow freezing in contrast to the rapid form causes formation of large ice crystals within spaces in the fibres. Upon thawing, the fibres sometimes rupture resulting in low quality meat.
Figure 4 presents a schematic breakdown of slaughter products. Apart from the carcass, other edible meat includes red offals (liver, kidney and heart), grey offals (stomach, intestine, lungs and spleen) and dark offals (head and feet). The red offals can be given the same cooling treatment as the carcass, but the others should be sold quickly. If storage is desired the grey and dark offals should be held in a separate chamber and spread out to allow for more effective cold action.
FIG.4 SCHEMATIC BREAKDOWN OF RUMINANT SLAUGHTER PRODUCTS
Items above the broken line constitute saleable meat. The scheme as a whole is highly generalized and may not represent the state of affairs in all areas. Some communities utilize red offals only for food apart from the carcass.
In others, as much meat as possible is salvaged from the animal including scrapings from hides and skins. The latter are sometimes shaved, cut up and brought to prolonged boiling to soften for use. Blood in most places is flushed into effluents and under normal conditions of slaughter does not constitute a by product, but waste.
The development of cold-storage in large municipalities should be made a matter of deliberate policy. This becomes necessary as the population increases and the demand for meat goes up. Refrigeration also improves meat marketing especially at the cold store level where consumer selection for quality offers additional cash advantages to the butcher.
Traditions do change; thus the concept that meat storage can always be provided for indirectly by the animal in the live form may not always be valid. Disease and drought for instance are known to cause reductions in populations of livestock where fit and healthy animals could be slaughtered and stored for future use.