STUDY OF HYDROLYZED PROTEIN COMPOSITION, FREE AMINO ACID, AND TAURINE CONTENT IN DIFFERENT MUSCLES OF GALICIAN BLONDE BEEF

The aim of this study was to identify and quantify hydrolyzed and free amino acids including taurine in different muscles of the Blonde Galician breed. The main essential amino acids present in each of the muscles were lysine and leucine, with aspartic acid and glutamic being the most important in the non-essential fraction. The chemical score and the index of essential amino acids were calculated as correlation parameters of the biological value of the proteins, with the best values being obtained for the muscles longisimus dorsi and semitendinosus. An analysis was also carried out of the amino acid in the free fraction. Taurine was found to be the main free amino acid in all muscles, with the exception of the cardiac muscle, where histidine was the main one present. The muscles that presented higher amounts of taurine were the masseter muscle followed by semimenbranous, and biceps femori, where taurine represented 40, 35, and 31%, respectively, of the total content of the free fraction. PRACTICAL APPLICATIONS This study provides practical and useful information on the nutritional quality of muscles, which are widely consumed in Spain. Several of these muscles are highly appreciated by the consumers in restaurants such as, eye of round, sirloin, and masseter muscle. These results will be relevant for the cattle industry, because this data add information to the fatty acid profile description of samples studied in the same breed. It will be also useful for nutritionists in describing tables of the food composition.