Slaughtering and Processing of Livestock
Asia's livestock industry is growing. To compete with imported meat and meat products, the industry needs to have efficient slaughtering and processing systems.
This first step is to design a hygiene management system. This is needed even for very small plants. In fact, a good hygiene management system should be set up even before a plant begins its operations.
The hygiene management system should cover the whole process of slaughtering and meat processing, from when the animals enter the slaughterhouse to shipment of the final products. It should include all the equipment and how it is set up, and how that equipment is cleaned and maintained. It should cover water management. All the water being used on-site must be clean, and all the wastewater must meet government regulations with regard to BOD and other limits. Finally, the hygiene management system must include training for employees in plant operations.
Quality Control: The Haccp System
HACCP (Hazard Analysis Critical Control Point) was a system originally set up when food was being produced for astronauts in the United States space program. The system was made public in 1971, and has since been adopted by many countries around the world, including many in Asia.
HACCP is basically a preventative system, designed to correct problems before they affect the safety of food products. It has seven parts.
- - Carrying out hazard analysis and assessment;
- - Determining the critical control points (CCPs);
- - Establishing critical limits for CCPs;
- - Monitoring critical limits;
- - Correcting deviations from critical limits;
- - Establishing a sound record-keeping system;
- - Verifying that the HACCP system is working.
Cutting up the carcass is a critical step in the HACCP system. Handling the carcass gives an opportunity for introducing bacteria or other contaminants. Control procedures for handling raw meat and poultry are as critical to safety as the final cooking stage.
Detecting Pathogens by Dna Probes
Many microscopic pathogens can contaminate food and cause serious illness. Salmonella spp. and Campylobacter spp. are among the most common. If these are present, it is important to detect them as quickly as possible, so the source can soon be found and the problem corrected.
The use of DNA probes and primers offers a quick and reliable means of detection. However, each probe or primer can be used to detect only a specific pathogen. What is more useful are systems which detect a range of bacteria simultaneously. New whole genome projects have been elucidating the genome sequences of dangerous microorganisms. This is a very promising approach. It leads to the development of biochips, which will be able to detect simultaneously multiple food pathogens and sequences of toxic genes.
Development of Products from Deboned Meat
Modern processing makes it possible to transform the secondary parts of the carcass into products which resemble steaks and other solid meats. The first flaked and formed products were developed in the 1970s in USA. They sold for about half the cost of solid muscle products. Today, fast-food chains are offering a wide range of restructured red meats, seafood and poultry meat. One example of a successful product is the McDonald's Chicken McNuggets.
Meat can be restructured in three ways. It can be flaked and formed; it can be chunked and formed; and it can be sectioned and formed. Sometimes processing uses a combination of these three methods. The reason for restructuring meat is to transform low-value carcass parts into products with a higher market value. They can be formed into sticks or nuggets of any shape or size desired. Another advantage is that they can be precisely measured, so that each serving is exactly the same as the others. This makes it easier to calculate the nutritional value and the cooked yield. It also makes cost accounting easier for mass distribution.
The disadvantage is that restructured meat may have an off flavor. Particularly in flaked and formed meat, oxidation may sometimes make the meat rancid (although this can be prevented by adding nitrate, phosphates etc.). Restructured meat can also have color problems, with splotches of green and brown material among the red. Most flaked and formed products are designed to be sold as frozen foods.
If deboned beef is being prepared in a country where BSE occurs (see over page), meat should never be taken from near the spinal cord.
Intermediate Moisture Meat Products
One of the oldest methods of preserving meat is to reduce the water content to produce intermediate moisture meat (IMM) products. This prevents or limits the activity of microorganisms in the meat. All over the world, traditional societies preserve meat by drying it in the sun or in an oven to make IMM. The other way of processing meat into IMM is to add soluble ingredients such as salt or sugar with other humectants to reduce water activity.
Modern meat processing is looking for new ways of drying meat and suppressing microbial activity. It is also important to maintain a good reddish color in the final product. At the same time, the preservatives used must be safe for human health when eaten for many years.
Utilization of Meat by-Products
At one time, organ meats such as liver and kidney fetched a higher price in many Asian countries than steak. Nowadays, these parts of the carcass have fallen out of favor. Traditional markets for organ meats and other edible meat by-products are gradually disappearing, because of health concerns and poor economic returns.
Meat processors are looking for other ways to use by-products. Since more than 50% of animal by-products are not suitable as food, processors are developing new non-edible uses, including pet foods, pharmaceuticals, cosmetics and livestock feed. Often, it is the use of these by-products which determine whether a meat processing plant is profitable. They make up a large part of the carcass. For example, by-products such as organs, fat, skin, feet and bones make up around 66% of a cattle carcass.
It has been suggested that 7-12% of the income from slaughter comes from the sale of animal by-products. Since the cost of live animals often exceeds the selling price of the meat, it is the value of the by-products which must cover the cost of slaughter and generate a profit.
Today, many new techniques are available for using these parts of animals more efficiently, and making them into new, high-value products. It is important that the Asian meat industry keeps up to date. Competition from imports is increasing. If Asian livestock producers are to survive, they will need access to efficient slaughtering and processing plants which will give them a good price for their animals.
Index of Images
Figure 1 Inspecting Meat Prior to Processing It
