Abstract:

A comparative investigation on the fatty acid composition of skeletal muscles of Maiya yak and common yellow cattle and an analysis on the relationship between fatty acid composition and myoglobin oxidation were conducted. The daily oxidation rates of myoglobin for Maiya yak and common yellow cattle were 1.54% and 5.03%, respectively, and the daily lipid oxidation rates (TBARS) of skeletal muscle were 0.088/d and 0.049/d. These data indicate that the oxidation rates of myoglobin and lipid in yellow cattle skeletal muscle were both significantly faster than those in Maiya yak skeletal muscle (P＜ 0.5). The analysis of fatty acid composition showed that the relative content of saturated fatty acids in Maiya yak skeletal muscle was 45.94%, significantly higher than that in yellow cattle skeletal muscle of 38.01% (P ＜ 0.5), while yellow cattle skeletal muscle displayed significantly higher content of polyunsaturated fatty acids than Maiya yak skeletal muscle (P ＜ 0.5). The difference in fatty acid composition might be one of the main reasons causing the difference in myoglobin oxidation between both beef skeletal muscles.

Key words: yak meat, myoglobin, fatty acid analysis, lipid oxidation