Characteristics of intramuscular collagen in two sheep breeds

Abstract

The Texel breed, new to New Zealand, gives superior meat production, particularly from the more valuable hindquarter. This study examines the intramuscular collagen properties in Texel x Romney and Romney x Romney lambs. Collagen is responsible for the so-called background toughness in meat. High-quality meat cuts often contain low concentrations of collagen which is relatively soluble when heated. Therefore, the intramuscular collagen characteristics of the two groups were compared as one aspect of meat tenderness. The Texel-sired lambs grew more rapidly but the difference was not significant. Texel muscle weights were heavier at each of three slaughter ages (100, 150, and 215 days) for two hindquarter muscles, semimembranosus (P < 0.05) and biceps femoris (P < 0.01). The forequarter muscle (supraspinatus) was statistically unaffected by breed. As expected there was a marked decrease in collagen solubility with age for both muscles (P < 0.001), but little effect on concentration. Collagen concentration and solubility in the two hind muscles were unaffected by breed. Thus, between 100 to 215 days—a desirable and obtainable age range for the slaughter of lambs in New Zealand— intramuscular collagen properties, as determinants of meat quality, are unlikely to be affected by use of Texel sires. © 1994 Taylor & Francis Group, LLC.