Analysis of Muscle Fatty Acid Characteristics of Tibetan Sheep of Different Ages
In order to investigate the fatty acid content and composition characteristics of Tibetan sheep muscle at different ages under natural grazing conditions,18 Tibetan sheep ewes(6 at each age)were selected from different ages(1.5,3.5,6.0 years).The fatty acid composition and content of longissimus dorsi muscle,foreleg muscle and hindleg muscle were determined by gas chromatograph.The results showed that there were significant differences in fatty acid composition and content in muscle of Tibetan sheep at different ages.In longissimus dorsi muscle,the content of myristic acid(C14∶0)in 3.5 years old group was significantly higher than those in other groups(P<0.05),while there was no significant difference in the contents of myristic acid(C17∶1),linoleic acid(C18∶2n6c)and arachidonic acid(C20∶4n6)among 3 age groups.In the foreleg muscle,the contents of myristic acid(C14∶1)and linoleic acid(C18∶2n6c)in 3.5 years old group were significantly higher than those in other groups(P<0.05).In hindleg muscle,stearic acid(C18∶0)content in 6.0 years old group was significantly higher than that in 1.5 years old group(P<0.05).The ratio of polyunsaturated fatty acids to saturated fatty acids(P/S)in the 3 muscle tissues ranged from 0.280 to 0.798,among which,the P/S in the foreleg muscle was significantly higher in the 3.5 years old group than in the other groups(P<0.05),and in the hindleg muscle,the P/S in 1.5 years old group was significantly higher than that in 3.5 years old group(P<0.05).Therefore,the composition and content of fatty acids in different muscle tissues of Tibetan sheep were more advantageous in the 1.5 years old group,that was the younger the Tibetan sheep were in adulthood,the better the meat quality had the edible value and the potential to produce high-grade mutton.Above results provided a reference for the nutritional value assessment and industrialization development and utilization of Tibetan sheep meat of different ages.