A 12-wk double-blind study was conducted to determine the effect of oral zinc supplementation upon serum total cholesterol, lipoprotein-cholesterol fractions, and serum triglycerides in white males. The subjects were randomly assigned to one of three treatment groups and consumed either a placebo tablet (n = 9), 50 mg Zn/d (n = 13), or 75 mg Zn/d (n = 9) as Zn gluconate. Serum total cholesterol, low-density-lipoprotein (LDL) cholesterol, very-low-density-lipoprotein (VLDL) cholesterol, and triglycerides were not affected by Zn supplements. However, serum high-density-lipoprotein (HDL)-cholesterol levels in subjects assigned to the 75 mg Zn/d group were significantly lower at weeks 6 and 12 than those for the placebo group and lower at weeks 6, 8, and 12 than at baseline; subjects assigned to the 50 mg Zn/d group had lower serum HDL-cholesterol levels at week 12 than did the placebo group and lower at week 12 than at base line.

Four methods of TBA analysis were used to study lipid oxidation in cooked longissimus and biceps femoris muscle from 10 antelope, deer, elk and beef animals. Pigment characteristics and total lipid were also evaluated to determine their effect on lipid oxidation. Differences (P < 0.05) existed among species for all TBA methods studied. Differences in pigmentation, percent lipid and phospholipids existed (P < 0.05) among methods of TBA analysis and among species. No one factor was consistently correlated with degree of lipid oxidation for any of the methods or species studied. Beef tended to be higher in percent fat and lower in total pigment and percent hemoglobin than tissue from the other species. Beef also tended to produce TBA numbers which were higher than those from antelope, deer or elk.

Twelve top round roasts from two Utility-grade cows were randomized and cooked by microwave, convection or conventional methods after epimysial tissue had been inserted into each roast. The freshly cooked and stored roasts were evaluated for rancidity using three TBA methods, and textural determinations were made on epimysial tissue. TBA numbers increased from day 0 through day 11. Shear values for epimysial tissue from S-year old animals cooked by microwave tended to be lower than those for tissues cooked by convection or conventional methods, but no differences in cooking method were observed for tissue from l-year old animals.

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