Research On The Nutrition Characteristic And The Impact Of Temperature On The Fatty Acids Of Yak And Yellow Cattle

There were two independent experiments were carried on,of which Yak and Yellow cattle were selected as trail animals.The fat samples from three organization of intramuscular, mesenteric fat and perirenal fat of Yak and Yellow cattle were taken for the study.Fat was extracted by using the methods of cold extraction,the fatty acids profile of each depot was analyzed separately by GC,in addition,the statistical procedures of SPSS16.0 were applied for data analysis.Two aspects such as fatty acids profiles of each organization and the perirenal fat fatty acids changes under different processing and treatments.Statistical analysis in variation of fatty asids profile among different organization between cattle breeds,variation in different sex between Yak and Yellow cattle and fatty acids changes under different temperature and power.Therefore,a comprehensive understanding different of the fatty acids content and profiles between Yak and Yellow Cattle and the fatty acids under different processing and treaments.(1) The content of saturated fatty acids(SFA) from intramuscular fat of Yak are 50.55%.Among the SFA of palmitic acid(C16:0) and stearic acid(C18:0) comprised the largest proportions of fatty acids in intramuscular fat of yak. And the content of unsaturated fatty acids(UFA) from intramuscular fat of Yak are 49.23%. The monounsaturated fatty acid (MUFA) of UFA was found to contain the highest percentage of oleic acid(C18:1) and the contain of polyunsaturated fatty acids are not high. The content of SFA in Yak is significantly lower than that of yellow cattle(P<0.01)and UFA is significantly higher than that of yellow cattle(P<0.01).At the same time, the P/S of nutritive index in intramuscular fat of Ma Qu Yak is significantly higher than that of yellow cattle(P<0.01)and n-6/ n-3PUFAs is significantly lower than that of yellow cattle(P<0.01).(2) The content of SFA in mesenteric adipose and perirenal fat from Yak is significantly lower than that of Yellow cattle.(P<0.01)In addition, among the SFA of palmitic acid(C16:0) and stearic acid(C18:0) comprised the largest proportions of fatty acids. The content of UFA in mesenteric adipose and perirenal fat from Yak is significantly higher than that of Yellow cattle(P<0.01).In addition, the monounsaturated fatty acid (MUFA) of UFA was found to contain the highest percentage of oleic acid(C18:1) and the contain of polyunsaturated fatty acids are not high. At the same time, the P/S of nutritive index in mesenteric adipose and perirenal fat of Yak is significantly higher than that of yellow cattle(P<0.01)and n-6/ n-3PUFAs is also significantly higher than that of yellow cattle(P<0.01).(3)The results show that the content of SFA in perirenal fat from Yak is proportional to temperature and significantly increased (P<0.05 or P<0.01)by heating.When the center temperature of perirenal fat is up to 90℃and 120℃,the SFA increased by 11.82% and 28.33%.And when the center temperature of perirenal fat is up to 150℃,the SFA inceresed by 40.94% and the content of SFA is 80%.The content of UFA in perirenal fat from yak is inversely proportional to temperature and significantly decreased(P<0.05 or P<0.01).The content of UFA is only 12.63% in total fatty acids.