Review: The Role of Collagen in Meat Tenderness

Abstract

Meat tenderness is a major factor affecting the consumers’ assessment of meat quality. Collagen is an abundant connective tissue protein and is a contributing factor to variation in meat tenderness and texture. It is found in three specific regions in muscle and in various forms and types. Collagen molecules are bound together through intermolecular crosslinks that help provide structure and strength. These crosslinks are initially reducible, but over time are replaced by mature, thermally stable, and less soluble crosslinks. These mature crosslinks, rather than the total amount of collagen, are the key factors in collagen-related toughness. The proportion of mature to reducible crosslinks increases with age, resulting in older animals that often have less tender meat than younger animals. Collagen crosslinks are also affected by growth rate, nutrition, and genetics. Collagen plays major roles in cooked meat as well. As collagen fibrils are heated during cooking, they shrink, resulting in a fluid loss and less tender meat. They also act to hold muscle fibers together after shrinkage. Post-mortem degradation of collagen and the use of collagenases appear to play a role in providing the desired tenderness and texture by altering the connective tissue structure. Collagen is very important in maintaining acceptable texture; however, high amounts of crosslinks can greatly decrease tenderness and consumer acceptability.