title: Effect of breed and nutrition on the productive traits of beef cattle in south-east Brazil: Part 3-Meat quality.
abstract: Significant differences in a number of economically important appearance and palatability traits were recorded between the Bos indicus and Bos taurus breeds. Muscles from the Charolais and Canchim animals were consistently and significantly lighter in colour than those from the zebu breeds, even after pH effects had been taken into account. Differences were shown to be directly related to variations in muscle myoglobin levels, but may have been complicated by observed textural differences. Muscles from the zebu animals were not noticeably coarser grained, having significantly larger fibre diameters and fibre bundle sizes. The inferiority of the Bos indicus breeds in terms of muscle tenderness was clearly demonstrated. Significantly higher shear force values were recorded in all muscles from the Nelore and Guzera breeds, except the Psoas major. These differences were also detected by taste panel evaluation. Major differences between breeds were demonstrated in the thermo-stability of extracted intra-muscular connective tissue elements, being highest in the zebu breeds, intermediate in the Canchim and lowest in the Charolais. These solubility characteristics were thought to be due to differences in the relative proportions of genetically different collagen types in the muscles and an association between coarseness of texture and toughness was shown.
authors: Tropical Products Institute, Industrial Development Department, Culham, Abingdon, Oxfordshire OX14 3DA, Great Britain.
authors: G A
authors: GA
authors: Norman