Interrelationships between meat quality traits, texture measurements and physicochemical characteristics of M. rectus abdominis from Charolais heifers.

Ninety-nine Charolais heifers were used to study the variability of meat quality traits in relation to the physicochemical characteristics of M. rectus abdominis. The heifers of the same trade class were slaughtered at 33months of age (±4months) and 381kg carcass weight (±31kg). Muscle and bone development scores were evaluated before slaughter. Carcass weight, slaughter age and life average daily gain were recorded. Shear force measurements and meat quality traits were evaluated after 14days of aging. Some physicochemical characteristics were measured 24h post-slaughter. Tenderness was correlated with slaughter age (r=-0.31), bone development (r=-0.22) and life average daily gain (r=+0.37). Tenderness was significantly related to total collagen content (r=-0.24), lipid content (r=+0.27) and I myosin heavy chain proportion (r=+0.24). Juiciness was positively correlated with lipid content (r=+0.31) and I myosin heavy chain proportion (r=+0.20). Flavor intensity was correlated with lipid content (r=+0.26) and mean fiber area (r=+0.24). Shear force was correlated with total collagen, lipid and 27K proteasome sub-unit contents. Taking animal characteristics and muscle properties together in a multiple regression analysis increased the explained tenderness variability to 33%. The independent variables listed in order of importance were life average daily gain, total collagen content, bone development, lipid content, I myosin heavy chain isoform proportion, shear force of broiled meat and slaughter age.