Feeding Agro-Industrial By-Products to Light Lambs: Influence on Meat Characteristics, Lipid Oxidation, and Fatty Acid Profile

SIMPLE SUMMARY: Consumers demand safe and healthy animal products produced with minimal environmental impact. The use of agro-industrial by-products in animal feeding can alleviate pollution caused by their accumulation, but investigations into their effects on animal-product quality are required. We analyzed the influence of replacing 44% of conventional feeds in a high-cereal concentrate (CON) with agro-industrial by-products (BYP concentrate; distillers dried grains with solubles, dried citrus pulp, and exhausted olive cake) on meat quality of fattening light lambs. Two groups of lambs were fed each of the concentrates and barley straw ad libitum from 13.8 to about 26.0 kg of body weight. The pH, chemical composition, color, and texture parameters of the meat were not affected by the type of concentrate. Feeding the BYP concentrate significantly reduced lipid oxidation of meat after 6 days of refrigerated storage, which might be related to the greater content of polyphenols in this concentrate. Compared with CON-fed lambs, the meat from BYP-fed lambs had lower saturated and greater polyunsaturated fatty acid content. In summary, feeding the tested by-products did not change the composition of the meat but increased its shelf-life and improved its fatty acid profile. ABSTRACT: The aim of this study was to assess the effects of replacing 44% of conventional feeds in a high-cereal concentrate (CON) with by-products (BYP concentrate; 18% corn distillers dried grains with solubles, 18% dried citrus pulp, and 8% exhausted olive cake) on the meat characteristics and fatty acid (FA) profile of fattening light lambs. Two groups of 12 Lacaune lambs were fed concentrate and barley straw ad libitum from 13.8 to 26.0 kg of body weight. There were no differences (p ≥ 0.130) between groups in the pH, chemical composition, color, and texture parameters and in the estimated proportions of pigments in the longissimus dorsi. Feeding the BYP concentrate reduced the concentration of thiobarbituric acid reactive substances (TBARS) in the meat after 6 days of refrigerated storage (unmodified atmosphere), probably due to the greater polyphenol content in this concentrate. Compared with CON-fed lambs, the meat and the subcutaneous fat from BYP-fed lambs had lower saturated and greater polyunsaturated FA content as well as greater n-6/n-3 FA. In summary, feeding a blend of corn distiller dried grains with solubles, dried citrus pulp, and exhausted olive cake did not change the composition of the meat but improved its antioxidant status and FA profile.