Physicochemical Quality, Fatty Acid Composition, and Sensory Analysis of Nellore Steers Meat Fed with Inclusion of Condensed Tannin in the Diet.

This study was conducted to test the effect of dietary tannin on the fatty acid profile and sensory attributes of meat from Nellore steers. Thirty-two Nellore bull male were distributed in a completely randomized design and fed diets with condensed tannin extract as follows: 0, 10, 30, and 50 g/kg total DM basis. The physicochemical composition of the meat, lipid oxidation, fatty acid profile, flavor, tenderness, and overall acceptance were evaluated. There was a linear decrease (P ≤ 0.05) on lipid content, tenderness, cooking weight loss, myristic, palmitic, and oleic acids in meat as tannin increased in the diets. The total saturated and monounsaturated fatty acids, the atherogenicity index decreased. However, a linear increase (P ≤ 0.05) was observed for linoleic, linolenic, arachidonic, eicosapentaenoic, and docosapentaenoic acids. The physicochemical characteristic of the meat, such as moisture, ash, and protein contents, water retention capacity, final pH, Warner-Bratzler shear force, collagen, and color indexes (lightness, redness, yellowness, and chrome) did not change with dietary tannin. Also, CLA, n-6:n-3 ratio, Δ9 -desaturase, and elongase activity were not different among diets. In conclusion, condensed tannin linearly increases unsaturated fatty acids and decreases the atherogenicity index of meat; thus, it can be recommended at the highest level (50 g/kg DM) in the diet of Nellore steers.

PRACTICAL APPLICATION: Agriculture byproducts plays an important part in the diet of ruminant animals and consequently on food chain and has implications for the composition and quality of the livestock products (milk, meat, and eggs) that people consume. Feeding tannin to steers increases the amount of unsaturated fatty acids and meat tenderness, with a concomitant reduction on saturated fatty acids and the atherogenicity index in meat. Thus, we recommend adding tannin to steer diets to reduce the risk factors for cardiovascular diseases in red meat for human consumption.