MEAT

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MEAT
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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.

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Types of Meat

• Beef Cow, cattle
• Mutton Goat, sheep
• Pork Pig
• Veal Calf
• Venison Deer

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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)

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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.
• Vitamins a good amount of B group vitamins
• Minerals A good amount of iron and phosphorus.
• Cholesterol
• Water - 60

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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

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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.

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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.

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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.

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What makes meat tough or tender?

• 3. Fat distribution

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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.)

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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

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Effect of heat

• Dry heat
• Protein starts to coagulate at 60C
• 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.

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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.

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Effect of heat

• Moist Heat
• Protein starts to coagulates at 60C 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.

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Effect of heat

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

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Which is more difficult to digest?

• Meat
• Or
• Fish

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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.

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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

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Marbling of fats in beef