MEAT

Structure  Meat is the flesh of animals reared for food. E.g. cows, goats, pigs.  Meat is composed of bundles of muscle fibres joined by strong connective tissues with fat scattered between.  The main protein in muscles is myosin and actin.  Connective tissues contain the protein collagen and elastin.

Types of Meat  Beef:Cow, cattle  Mutton:Goat, sheep  Pork:Pig  Veal:Calf  Venison: Deer

Offals edible internal organs of animals E.g.: brain, kidney, heart, liver, tripe, tongue Very good source of  iron and vitamin B12 (liver and kidney)  Vitamin A (liver)  Glycogen (liver)

Nutritive Value Protein: Myosin, globulin collagen (in connective tissue) Fats: particularly lamb, pork and beef, gives flavour, moisture and texture. Some fats are found between muscle fibre of lean parts of meat. This is known as marbling. marbling Vitamins: a good amount of B group vitamins Minerals: A good amount of iron and phosphorus. Cholesterol Water - 60%

Factors to consider when choosing meat Good characteristic colour No unpleasant smell Firm and elastic to touch, moist but not wet. Grain should be fine and even. Avoid too much bone, gristle or fat

What makes meat tough or tender? 1. Age  In young animals, the muscle fibres are short and finer. Meat is tender.  As the animal matures, the muscle fibre thickens and there is more connective tissues. Thus the meat from the older animals is tougher than the meat from young animals.  There is also more fat in older animals.

What makes meat tough or tender? 2. Part of the animal  Meat from the leg is usually tougher than meat from the ribs because the leg muscles work harder.  The more the animal works the muscle, and the tougher it will be.

What makes meat tough or tender? 3. Fat distribution When fat is evenly distributed throughout the muscle, the meat is usually more tender and of a better flavour than meat that has concentrated visible deposits of fats.

What makes meat tough or tender? 3. Fat distribution

Methods used to tenderize meat Mincing or grinding Cubing, slicing - Cut meat across the grains. Pounding with a meat pounder or the blunt edge of a cleaver Sprinkling with commercial tenderizer e.g. papain (papaya) Marinating e.g. Soya sauce, acids (lemon juice, vinegar, tomato) yoghurt, wine. Cooking slowly with water e.g. stewing, boiling. (Collagen in the connective tissue changes into gelatin which dissolves in the water. This causes the meat to come apart easily.)

Reasons for cooking meat To kill any harmful bacteria To make it tender and more digestible To make it look, taste and smell more appetizing To preserve food for later use To develop extractives for flavour

Effect of heat Dry heat  Protein starts to coagulate at 60°C  Red meat changes to brown  Fats melts and goes crisp making meat juicy  Meat shrinks as protein coagulates and shortens. - If meat is overcooked, juices are squeezed out onto surface, which might then dry out.  Connective tissues (containing collagen) becomes tougher.

Effect of heat Dry heat cooking (roasting, baking, grilling) is best for tender meat which has little or no collagen and elastin. The elastin will contract during cooking, squeezing out the meat juices causing the meat to be dry.

Effect of heat Moist Heat Protein starts to coagulates at 60°C when outer layer is sealed lightly. Red meat changes to grayish brown. Fat melts partly and seeps into the gravy. Meat shrinks a little. The longer the cooking, the greater the shrinkage. Juices tend to come out of the meat into the gravy, developing a rich flavour in the gravy, with slight loss of flavour of meat. Collagen in connective tissue is converted to gelatin. Overcooking results in the meat falling apart.

Effect of heat Moist heat method (boiling, stewing, frying) is recommended for cooking tough meat as it is a slow process.

Which is more difficult to digest? Meat Or Fish

Meat is more difficult to digest than fish. Fish has no elastin (the wall of muscle fibre, very tough, cannot be changed by cooking but can be broken down mechanically or removed) Fish consists of short, fine fibres, bound together by a small amount of fine connective tissue.

Ways to reduce fat content in meat Use more poultry, reduce consumption of red meat Avoid frying. Grill or bake instead Remove fat before cooking

Marbling of fats in beef