Cholesterol oxidation in frozen dark chicken meat:: influence of dietary fat source, and α-tocopherol and ascorbic acid supplementation

A factorial design assessed the effect of dietary fat source (beef tallow, fresh and oxidized sunflower oils, and linseed oil), and alpha -tocopheryl acetate (alpha -TA) and ascorbic acid (AA) supplementation (225 and 110 mg/kg feed, respectively) on the cholesterol oxidation product (COP) content and 2-thiobarbituric acid (TBA) values in raw and cooked dark chicken meat vacuum packaged and stored at -20 degreesC for 7 months. COP determination showed good linearity, recovery and precision. Dietary alpha -TA was highly effective in protecting raw or cooked meat from cholesterol and fatty acid oxidation, regardless of its degree of unsaturation. In contrast, AA supplementation was ineffective and even promoted oxidation in raw meat from broilers fed unsaturated fat diets that had not been supplemented with alpha -TA. Oxidation values (raw or cooked meat) from alpha -TA or alpha -TA+AA supplemented diets were not statistically different (P > 0.05). TEA and COP values were significantly correlated in raw samples (r = 0.6466, P = 0.0001). (C) 2000 Elsevier Science Ltd. All rights reserved.