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will improve the eating quality of the prime cuts.

When purchasing meat or selecting it from stores, therefore, marbling can be used as a visual
indicator of good flavour. Be aware that as marbling increases, flavour intensity increases
slightly, yet tenderness does not always improve.

3. Meat colour. Meat colouration is caused by a pigment called myoglobin-the primary oxygen-
carrying pigment of muscle tissues.

Animal muscle turns to meat after slaughtering. Meat is surrounded by a layer of connective
tissues, consisting almost entirely of protein collagen. Meat tissues are composed of three
main factors: water, protein (connective t issue) and fat. Carbohydrate also appears in meat
as it gives the browning effect of meat when cooked. Without this carbohydrate, the
desirable flavour and appearance of browned meat would not be achieved.

Meats are mainly referred as red or dark and white meat. Red or dark meat is mainly made
up of muscles with fibres that are ca lled slow fibres. These muscles are used for extended
periods of activity, such as standing or walking and need a consistent energy source. The
protein myoglobin stores oxygen in muscle cells, which use oxygen to extract the energy
needed for activity. Myoglobin is a richly pigmented protein. The more myoglobin there is in
the cells, the redder or darker, the meat is. Red meat is red because the muscle fibres that
make up the bulk of the meat contain a high content of myoglobin, a protein similar to
haemoglobin in red blood cells, acts as a store for oxygen within the muscle fibres.

White meat is made up of muscles with fibres that are called fast fibres. Fast fibre muscles
are used for quick bursts of activity, such as fleeing from danger. These muscles get energy
from glycogen, also stored in the muscles. White meat as in fish has a translucent glassy
quality when it is raw. Meats such as veal and pork are also categorised as white meat. Veal
meat is white because it is slaughtered after the calf has been milk fed. Pigs are not active
animals, so their bodies contain more fat than other animals. Pig muscles do contain
myoglobin, but the concentration is not as heavy as it is in beef.
Both veal and pork are white meats because there is less usage in the muscle and myoglobin
content is low-their muscles are less developed and do less work. Therefore, pigs and calf
have a lower concentration of myoglobin in their muscles than cows.
Chickens have a mixture of both dark and white meat. Chickens spend time walking around
and standing. Their thigh and leg muscles are used constantly, so the meat from these parts
is slightly darker than the breast. Chicken (breast), pork and veal are slightly pink or white,
before or after cooking.

Cows spend a lot of time standing, walking etc and so their muscles are constantly being
used. Therefore, beef has a fairly high concentration of myoglobin and is dark red.

Juiciness and tenderness are two very important factors when it comes to meat quality.
The more a muscle is used, the stronger and therefore tougher, the cut of meat will be.

Factors that also influence tenderness and juiciness are: the animal's age at slaughter, the
amount of fat and collagen (connective tissue) contained in particular cuts and to a small
degree, brining.
Meat colour can also be influenced by the speed with which a carcase goes through rigor
mortis, by the age of the animal (the older an animal is the more myoglobin will be held in
the muscles, hence the colour will be darker), pre-slaughter stress, electrical stimulation
(which produces a more even meat colour) and post-slaughter handling. Preslaughter stress
changes the acidity (pH) of muscle tissue and the colour of meat. Meat from a stressed
animal will have, due to increased acid content, a dark colour and will feel soft or mushy to