Meat tenderness

The most important aspect of meat quality is its eating quality or overall eating satisfaction, being a function of the combined effects of tenderness, juiciness, and flavour. Meat tenderness is the most difficultly predicted trait, but it is very important to meat quality and consumer acceptance. Tenderness is based on ease of chewing that is contributed by many factors. Among them, the fibrous nature of muscle contributes to chewing resistance

The fact that many myofibrils are arranged in register across the muscle fibers leads to more strength for muscle and decreases muscle tenderness.

Variation in beef tenderness may be attributed to breed (genetic status), carcass composition, and environmental factors (chronological age, time on feed, implants and ante-mortem stress). The three factors that determine meat tenderness are background toughness, the toughening phase and the tenderization phase. While the toughening and tenderization phases take place during the post-mortem storage period, background toughness exists at the time of slaughter and does not change during the storage period.

The tenderization process is estimated to begin soon after slaughter (perhaps as soon as 3 h, but it is highly variable among individual carcasses).

Current evidence suggests that proteolysis of key myofibrillar proteins is the cause of meat tenderization. These proteins are involved in:
*Inter-myofibril linkages (e.g., desmin and vinculin),
*Intra-myofibril linkages (e.g., titin, nebulin, and possiblytroponin-T),
*Linking myofibrils to sarcolemma by costameres (e.g. vinculin and dystrophin), and
*The attachment of muscle cells to the basal lamina (e.g. laminin and fibronectin).

The function of these proteins is to maintain the structural integrity of myofibrils.
Meat tenderness

Meat texture

The quality of meat is determined by a number of factors that affect palatability (tenderness, juiciness and flavor). Texture is one of the most important characteristics of meat. It is a feature that can be defined by certain homogeneous properties which are detected by human senses relating to vision, hearing, somesthesis and kinesthesis.

Meat juiciness plays a key role in meat texture, probably contributing to its variability. Juiciness means the amount of juice “liberated” during chewing the meat.

Properties of beef texture include both initial (first bite with incisors) and overall tenderness (after multiple chews) as well as more complex sensory attributes of chewing and mouthfeel with multiple descriptors such as fiber cohesiveness, adhesion, friability, chew count, mealiness, mushiness, softness, amount of residual connective tissue, rubberiness, and hardness.

The tenderness of cooked meat will be largely influenced by connective tissue and myofibrillar components. This is because during heating, a number of chemical changes associated with the muscle fibers and connective tissues occur.

The textural properties of meat are often adapted by food processing, where the aim is often to make the structure of meat, and food in general, more delicate and easier to chew.

The most common method to measure meat texture, the Warner–Bratzler shear force, uses a standardized blade, but has many other unstandardized aspects that limit absolute comparisons of results. Warner-Bratzler Fixtures measure the force required to cut through a piece of meat. The fixture consists of a steel frame supporting a triangular shear blade. This test measures the maximum force as a function of knife movement and the compression to shear (cut off) a sample of meat. The result of this measurement shows the hardness (toughness) of meat.
Meat texture