The Make Up of Meat
Put simply, meat is the muscle of an animal that has been processed for human consumption. Meat is rich in protein, minerals and vitamins and is composed primarily of three basic materials.
The percentage of these depends on many factors but the single biggest determining factor is the age of the animal. Generally speaking, the older the animal the less water and the more fat. The younger the animal, the more water and the less fat.
The three main materials of meat are:
WATER 43-65% | PROTEIN 12-30% | FAT 5-45%
Meat contains no carbohydrate – this is because any that present in the live animal in the form of glycogen would have been broken into lactic acid at the time of slaughter.
All muscles are composed of fibres, connective tissue, and fat.
Meat is composed of long thin cells called filaments. These filaments are bound together to form muscle fibres and fibres, in turn, are bound together by connective tissue to form bundles.
As a basic rule the more work a muscle does or the more weight a muscle has to support, the tougher it will be as a meat product. This is due to the filaments increasing which in turn increases the bundle causing the muscle as a whole to become larger, stronger and therefore not as tender as muscles that are called upon to do less.
Connective tissue is made up of elastin, reticulin, and collagen. These proteins surround and sheath muscles, forming tendons which hold muscle directly to bones. Just as with muscles, the older the connective tissue the larger and stronger it will be. This is best seen in the tendon that runs down each side of a bovine’s neck along into the loin. This large tendon aids greatly in helping to hold the cow’s head up so as not to leave this heavy job to muscles alone.
The quality and eating characteristics of a cut of meat are generally based on the quantity, type and distribution of connective tissue in a muscle. As a rule, use the following: grilling cuts contain less connective tissue and braising cuts contain more. The closer to the ground the muscle is located, the more work it will do and the more connective tissue will be present. The same rule applies closer to the head.
Fat serves three main purposes in the living animal and is a unique form of connective tissue in itself. Primarily insulating the body, fat protects the internal organs and store energy.
Fats fall into two classes: saturated fats that surround the internal organs like the kidneys and unsaturated fats such as intramuscular fats more commonly known as marbling.
The old saying that fat = flavour is true, believe it or not. As animals eat, their food is converted into energy. This energy is used immediately but it’s also stored for later use in the form of fat within the muscle bundles as intramuscular fats.
As the food an animal eats is stored as fats within the muscle, it’s safe to say that the quality, quantity, and type of food consumed will affect the flavour of a muscle.
This is why you may hear that pasture fed beef tastes earthy. It makes a lot of sense when you consider that pasture-raised animals ate grass that came directly from the earth.
Read more about the differences between grain fed and pasture fed beef here.