Dietary influence on lipid composition and oxidation of fresh and processed meat products

Abstract

Two experiments were conducted to evaluate the effects of diet on fresh and processed meat quality in beef. In experiment 1, steers and heifers (n = 48) were assigned randomly to one of four treatment groups and fed individually. Treatments were as follows: steam-flaked corn diet with no modified distillers grains with solubles (MDGS) or glycerin (CON); CON with 35% MDGS (MDGS); CON with 10% glycerin (GLY); and CON with 35% MDGS and 10% glycerin (MDGS/GLY). When cattle reached a mean weight of 590 kg, they were humanely harvested at a commercial abattoir. Strip loins and shoulder clods were removed from the right side of each carcass. Treatment had no effect any specific fatty acid (P > 0.05), vacuum purge loss (P = 0.75), cooking loss (P = 0.40), Warner-Bratzler shear force values (P = 0.94), strip steak L*, a*, or b* values (P > 0.05) or ground beef L*, a*, or b* values (P > 0.05). CON and MDGS had higher values for consumer overall liking and texture liking of strip steaks (P < 0.05). Treatment did not affect flavor liking (P < 0.05). In experiment 2, shoulder clods and inside rounds from 24 forage-finished steers were ground in groups, divided into five 35 kg batches, and assigned randomly to one of five antioxidant treatments: control (CON); ground wild rice (WR); rosemary extract (ROSE); cherry seed powder (CHERRY); rosemary and pomegranate extract blend (X). Each antioxidant was added at 1% and mixed into a batch for 1 minute. Batches were formed into patties and objective and subject color scores, sensory evaluation, and TBARS were measured. L* and b* did not differ between treatment (P = 0.49 and 0.66, respectively), however inclusion of CHERRY did increase a* values (P = 0.01). Texture liking was decreased with X compared to the WR and CHERRY (P = 0.006. Toughness was decreased with WR (P = 0.03) as compared to X and juiciness increased with the addition of CHERRY (P = 0.003). Overall liking, flavor liking, and off flavor were unaffected by treatment (P = 0.09, 0.07, and 0.06, respectively). TBARS values were lower with the addition of ROSE, CHERRY, and X on d0 than CON (P = 0.0005). WR was also lower on d7 than CON (P <0.0001).