Meat as raw material, non-meat ingredients and basic techniques in further processing of meat
TYPES OF ANIMAL TISSUE SUITABLE FOR MEAT PROCESSING
Meat is defined as those animal tissues which are suitable for use as food. These are the main soft tissues of the carcass: muscle, mainly skeletal (30– 65 percent), fatty (10–45 percent) and connective tissues. Other animal tissues used as food, and also to some extent in meat processing, are the internal organs including the blood.
Muscle tissue
The structural unit of muscle is a specialized cell, the muscle fibre, which constitutes 72–92 percent of the muscle volume. The membrane surrounding the muscle fibre is called the sarcolemma and the intracellular substance the sarcoplasm. The muscle fibre is composed of many myofibrils, which consist of thick and thin filaments (myofilaments). The special arrangement of these and the bands of myofibrils give the fibre a striated appearance under a microscope (cross-striated muscle). The filaments consist almost entirely of the myofibular proteins actin (thin 20– 25 percent) and myosin (thick 50–55 percent) (Fig. 122). Although they make up only 7 percent of muscle weight, they are mainly responsible for a very important property of meat, its ability to retain water and bind added water (water-holding capacity, WHC). The water-holding capacity is of particular importance in meat processing.