Quality and Chemical Composition of the Longissimus Thoracis from Bovine Genetic Groups Selected for the Production of High-Quality Meat

The growing demand for high-quality beef has driven the selection of bovine genotypes offering superior marbling and tenderness. This study evaluated meat quality parameters in heifers from four Nellore-based genetic groups: ½ Aberdeen Angus × ½ Nellore (AN), ½ Japanese Brown × ½ Nellore (BN), ½ Japanese Brown × ¼ Aberdeen Angus × ¼ Nellore (TriBAN), and ½ Japanese Black × ¼ Aberdeen Angus × ¼ Nellore (TriJAN). Thirty-two heifers (eight/group) were finished in commercial feedlots. Samples of the longissimus thoracis muscle were analyzed for physical attributes (pH, cooking loss, shear force, marbling, water retention capacity, colour), chemical composition, and fatty acid profile. In addition, animal performance (daily gain, final weight) was determined. A completely randomized design was used with the application of ANOVA and Tukey's test (α=0.05). The AN group showed the greatest final weight and daily gain (p<0.01). There were no significant differences between groups for pH, cooking loss, shear force, marbling (moderate), water holding capacity or colour (p > 0.05). Most of the fatty acids showed no differences between treatments (p > 0.05), with the exception of arachidonic acid (C20:4 n-6), which was found in higher (p < 0.05) concentrations in samples from the TriBAN group than in the other genetic groups under evaluation. In conclusion, despite differences in productive performance, the genotypes all produced meat of consistent quality, including tenderness, marbling, and fatty acid profiles commonly associated with high-quality beef.