DIETARY EFFECTS ON BEEF COMPOSITION. 4. Processing and Palatability Attributes

Abstract

The influence of dietary regimen of 104 half-sib Angus steers allotted to 1 of 13 combinations of hay, corn silage and corn concentrate, and of slaughter weights of 284 vs. 340 kg and 409 vs. 454 kg (live weight) on processing qualities and palatability of beef was studied. Measurements included postmortem glycolytic activity, water-and fat-binding capacity, textural properties, cooking losses, flavor and juiciness of selected muscles. Results showed that feeding regimens had a greater effect than did slaughter weight on qualities studied. Corn silage in the early dietary regimen of cattle weighing 284 and 340 kg resulted in significantly lower pH values 15 and 45 min post-mortem), higher amounts of glycogen at slaughter and greater water-and fat-binding capacity as compared to hay. Similar effects of early diet were noted for 5 and 45-min pH and water-binding capacity in cattle fed to heavier weights (409 and 454 kg); however, in these animals the early-hay diet resulted in greater muscle glycogen deposition than the early-silage diet. Steaks from animals fed corn silage in the early period were determined to be more tender by both shear values and panel scores and were more juicy and flavorful than those from hay-fed animals. These differences in palatability due to early diet were still evident after the cattle had been fed to heavier (409 and 454 kg) weights. When steers weighing 409 and 454 kg were grouped together, the effects of feeding regimen during the intermediate period were considerably less pronounced than those of the early feeding period.

Nutritional Effects on Beef Collagen Characteristics and Palatability

“…Variation in beef palatability due to nutritional treatment has been reported by Jacobson andFenton (1956), Garrigus et al (1969), Dube et al (1971), Kropfet al (1975), Bowling et al (1977), Smith et al (1979 and Burson et al (1980). These authors noted a decrease in beef palatability due to a lower plane of nutrition.…”

Volatile Concentration and Flavor of Beef as Influenced by Diet

“…May et al (1989) in-10.0 1 9.0 dicated that carcasses from grass-fed steers had higher pH than carcasses from steers finished on concentrate for a minimum of 84 days. The higher pH in carcasses from grass-fed cattle was attributed to two factors: (1) grass-fed steers are thought to be more susceptible to pre-slaughter stress (Bowling et al, 1977), (2) grass-fed steers tend to have less glycogen in their muscle which results in a smaller decrease in pH during rigor (Dube et al, 1971). Data by other researchers, however, suggested that, as demonstrated in our study, diet did not influence pH.…”

Principle of Meat Aroma Flavors and Future Prospect

“…Conversely, no significant difference in flavors existed between the grass and grain diets-fed animals [73]. The less desirable flavors were also seen on meats from the hay diets-fed animals compared to corn silage diets [74], while Oltjen et al (1971) [75] showed the opposite results. It has been hypothesized that majority of flavor effects due to feeding of forages is mainly due to changes in fatty acid compositions.…”