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Red meat

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Red meats

Red meat products come primarily from cattle, swine, sheep,

goats, and, to a lesser extent, horses and other animals.

Red meats are named according to their source:

Beef is typically from cattle over a year of age;

veal is from calves 5 months of age or younger (veal carcassesare distinguished from beef by their grayish-pink color of the

lean);

pork is from swine;mutton is from mature sheep;

lamb is from young sheep;

chevon is from goats, but it is commonly called goat meat.

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Dressing percentage

Animals are transported to packing plants, where they areprocessed. During the initial processing stage, the animals are

made unconscious by using carbon dioxide gas or by stunning

(electrical or mechanical). The jugular vein and/or carotid artery isthen cut to drain the blood from the animal. After bleeding, the

hides are removed from cattle and sheep. Hogs are scalded to

remove the hair, but skin is usually left on the carcass. A few

packers skin hogs, as it is more energy efficient than leaving the

skin on.

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After the hide or hair is removed, the internal organs are

separated from the carcass. Those parts removed from the

carcass are some times referred to the drop, viscera, offal, or

by product. Typically these are the head, hide, hair, shanks

(lower parts of legs and feet), and internal organs.

Dressing percentage (sometimes referred to as yield) is therelation of hot or cold carcass weight to live weight. It is

calculated as follows:

Dressing percentage= hot or cold carcass weight × 100

Live weight

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Average dressing %Meat productsSpecies/class60Beef Cattle

60VealCalves

72Pork Hogs

50Mutton/lambSheep/lamb

Dressing percentage

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Wholesale cuts of beef, veal, pork, and lamb

LambPork VealBeef 

LegLeg/hamLeg/roundRoundLoinLoinSirloinSirloin

RibBlade shoulderLoinShort loin

ShoulderJowlRibRib

Neck Arm shoulderShoulderChuck 

Foreshank SpareribsForeshank Foreshank 

BreastSideBreastBrisket

Short plate

Flank 

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Retail cuts of beef 

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Retail cuts of lamb

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Composition

Meat composition can be defined either in physical or chemical

terms. Physical composition is observed visually and with

objective measurements; chemical composition is determined by

chemical analysis.

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The major physical components of meat are lean (muscle), fat,

bone (Fig. 3.5), and connective tissue. The proportions of fat, lean,

and bone change from birth to slaughter time. Connective tissue,

which to a large extent determines meat tenderness, exist in several

different forms and locations. For example, tendons are composed

of connective tissues (collagen), which attaches muscle to bone.

Other collagenous connective tissues hold muscle bundles together

and provide the covering to each muscle fiber. Myofibrils are

component parts of muscle fibers; muscle fibers combined together

comprise a muscle or muscle system. Within the myofibrils are twotypes of myofilaments – namelt thick (myosin) and thin (actin)

filaments.

Physical composition

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Since muscle or lean meat is the primary carcass component

consumed. Chemical composition is important because it largelydetermines the nutritive value of meat. Muscle consists of 

approximately 65-75 % water, 15-20 % protein, 2-12% fat, and

1 % minerals (ash). As the animal increase in weight, water andprotein percentages decrease and fat percentage increases.

Fat-soluble vitamins (A, D, E, and K) are contained in the fat

component of meat. Most B vitamins (water-soluble) are abundant

in muscle.

Chemical composition

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The major protein in muscle is actomyosin, a globulinconsisting of the two proteins actin and myosin. Most of the

other nitrogenous extracts in meats are relatively unimportant

nutritionally. However, these other extracts provide aroma andflavor in meat, which stimulate the flow of gastric juices.

Simple carbohydrates in muscle are less than 1%. Glucose and

glycogen are concentrated in the liver. They are not tooimportant nutritionally, but they do have an important effect on

meat quality, particularly muscle color and water holding

capacity.

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All products other than the carcass meat are designated as

byproducts, even though many of them are wholesome and highlynutritious items in the human diet.

Among these byproducts are sheep pelts, hides, fats, blood, bones,

and intestines.

Byproducts