Effects of winter stocker growth rate and finishing system on: III. Tissue proximate, fatty acid, vitamin, and cholesterol content

Nutrient analysis of the Beef Alternative Merchandising cuts

The objective of this study was to generate raw and cooked nutrient composition data to identify Quality Grade differences in proximate values for eight Beef Alternative Merchandising (BAM) cuts. The data generated will be used to update the nutrient data in the USDA National Nutrient Database for Standard Reference (SR). Beef Rib, Oven-Prepared, Beef Loin, Strip Loin, and Beef Loin, Top Sirloin Butt subprimals were collected from a total of 24 carcasses from four packing plants. The carcasses were a combination of USDA Yield Grades 2 (n=12) and 3 (n=12), USDA Quality Grades upper two-thirds Choice (n=8), low Choice (n=8), and Select (n=8), and two genders, steer (n=16) and heifer (n=8). After aging, subprimals were fabricated into the BAM cuts, dissected, and nutrient analysis was performed. Sample homogenates from each animal were homogenized and composited for analysis of the following: proximate analysis, long chain and trans-fatty acids, conjugated linoleic acid, total cholesterol, vitamin B-12, and selenium. This study identified seven BAM cuts from all three Quality Grades that qualify for USDA Lean; seven Select cuts that qualify for USDA Extra Lean; and three Select cuts that qualify for the American Heart Association's Heart Healthy Check.

Fatty acid composition and interrelationships among eight retail cuts of grass-feed beef

The aim of this research was to evaluate: 1) fatty acid (FA) profile of eight retail cuts (eye of round, ribeye, top round, striploin, tenderloin, top-sirloin, underblade, ground beef) from grass-fed steers, 2) the association between striploin (longissimus muscle) FA profile and that from the other retail cuts, and 3) the changes in FA profile associated with retail cut total FA content. All of the retail cuts, except underblade and ground beef, would be considered lean (<10 g) based on total FA content. Total saturated fatty acids were positively correlated to total FA content; whereas, negative correlations were observed with total FA content and total monounsaturated and polyunsaturated fatty acids. No correlation was observed between total FA and CLA cis-9, trans-11. Striploin trans-11 C18:1 and CLA cis-9, trans-11 proportions, and n-6:n-3 ratio were positive and highly correlated with those in the other retail cuts.

Effect of feeding treatment during the backgrounding phase of beef production from pasture on: I. Animal performance, carcass and meat quality

This research evaluated effects of feedlot backgrounding on 40, 70 or 100% alfalfa hay diets (40 hay, 70 hay; 100 hay, respectively) or pasture grazing (Pasture) before pasture finishing, on performance and beef characteristics of Angus heifers. Ninety six female calves were allocated to the four feeding strategies. Backgrounding took place during 114 days and subsequent pasture finishing over 132 days. Heifers of each strategy were slaughtered after 114 days (end of the feedlot period) and at end of the study when all remaining animals were finished on pasture. Effects of backgrounding were associated with rate of gain. Backgrounding strategies 40 hay and Pasture resulted in the best performance. Beef attributes were similar. At the end of the feedlot period, 100 hay was smaller and leaner, less tender and less juicy. At the end of the study, Pasture and 40 hay heifers had on average the largest back fat thickness and intramuscular fat measurements. No treatment effects were detected for Warner-Bratzler shear force, muscle pH, muscle color and sensory panel attributes.

Long chain n-3 polyunsaturated fatty acid concentration and color and lipid stability of muscle from heifers offered a ruminally protected fish oil supplement

Beef heifers (n = 48) were offered, daily, a 1.5 kg ration that contained 0, 69, 138, and 275 g of ruminally protected fish oil (RPFO) fortified with vitamin E (5000 IU/kg). The fatty acid profile of neutral (NL) and polar lipids (PL) of neck muscle was analyzed by GC-FID. Minced muscle was displayed in an 80% O(2):20% CO(2) atmosphere under simulated retail display conditions. Muscle α-tocopherol concentrations did not differ. For PL, the proportions of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) increased (P < 0.05, linearly and quadratically, respectively). For NL, the proportion of EPA was not affected but DHA increased linearly and quadratically (P < 0.05). Supplementation did not affect color stability of ground beef, but lipid oxidation was higher (P < 0.001) for 275 g of RPFO on day 10 of display. In conclusion, supplementation with RPFO increased muscle EPA and DHA with no effect on color stability while lipid oxidation was increased only at the highest level of supplementation, after prolonged display.