To explore the fatty acid composition, functional active fatty acids and health index changes of yak ghee during storage by measuring the fatty acid status of yak ghee in Qinghai Tibet Plateau, four health indexes of atherosclerosis index (AI), thrombosis index (TI), health promoting index (HPI) and hypocholesterolemia/hypercholesterolemia ratio (HH) were used for the evaluation. Yak ghee from Haibei Tibetan Autonomous Prefecture of Qinghai province and Gannan Tibetan Autonomous Prefecture of Gansu province was stored at 4 ℃ for 0, 1, 2, 3, 4 and 5 months, and the fatty acids were analyzed by GC-MS. The results showed that palmitic acid, oleic acid and stearic acid were the dominant fatty acids in yak shortening during the storage period. The relative contents of polyunsaturated fatty acids (PUFA) in Haibei and Gannan shortening were 5.99%-4.62% and 7.77%-6.60%, and the monounsaturated fatty acids (MUFA) contents were 28.61%-26.42% and 29.51%-26.95% respectively. Compared with fresh shortening, Odd Carbon Fatty Acids (OCFA) in Gannan shortening decreased significantly (P<0.05) by 0.5%. Trans-10-C18∶1, docosapentenoic acid (DPA) and conjugated linoleic acid (CLA) were detected in Haibei and Gannan ghee, and they were still at high levels at the end of the storage which were (7.13±0.01)%, (0.12%±0.01)%, (4.04±0.01)% and (8.98±0.08)%, (0.10±0.00)% and (6.66±0.13)% respectively. With the extension of storage period, n-3 and n-6 fatty acids decreased significantly (P<0.05) accompanied with AI and TI significantly (P<0.05) increased, and HPI and HH significantly (P<0.05) decreased. However, fresh milk fat was still at a higher level compared with buffalo and Holstein. Meanwhile, the kinds and contents of fatty acids in yak ghee showed dynamic changes. By the end of the storage period, the relative contents of multiple functional fatty acids were still higher than those in Buffalo and Holstein milk fat. According to the evaluation of health index, the index of yak ghee was higher than that in Buffalo and other ruminant milk fat after 5 months of storage.
[1] BERNARD L, BONNET M, DELAVAUD C, et al.Milk fat globule in ruminant:Major and minor compounds, nutritional regulation and differences among species[J].European Journal of Lipid Science and Technology, 2018, 120(5):1700039.
[2] LIANG J J, ZHOU Q, KWAME AMAKYE W, et al.Biomarkers of dairy fat intake and risk of cardiovascular disease:A systematic review and meta analysis of prospective studies[J].Critical Reviews in Food Science and Nutrition, 2018, 58(7):1 122-1 130.
[3] BELURY M A.Dietary conjugated linoleic acid in health:Physiological effects and mechanisms of action[J].Annual Review of Nutrition, 2002, 22:505-531.
[4] O′CALLAGHAN T F, FAULKNER H, MCAULIFFE S, et al.Quality characteristics, chemical composition, and sensory properties of butter from cows on pasture versus indoor feeding systems[J].Journal of Dairy Science, 2016, 99(12):9 441-9 460.
[5] HANUŠ O, SAMKOVÁ E, KRÍŽOVÁ L, et al.Role of fatty acids in milk fat and the influence of selected factors on their variability—A review[J].Molecules (Basel, Switzerland), 2018, 23(7):1636.
[6] WIENER G, HAN J L, LONG R J, et al.Origins, Domestication and Distribution of Yak[M].Bangkok:RAP Publication, 2003:237-256.
[7] MÉNDEZ-CID F J, CENTENO J A, MARTÍNEZ S, et al.Changes in the chemical and physical characteristics of cow′s milk butter during storage:Effects of temperature and addition of salt[J].Journal of Food Composition and Analysis, 2017, 63:121-132.
[8] ERKAYA T, ÜRKEK B, DOĞRU Ü, et al.Probiotic butter:Stability, free fatty acid composition and some quality parameters during refrigerated storage[J].International Dairy Journal, 2015, 49:102-110.
[9] 杨静, 梁琪, 宋雪梅, 等.牦牛乳与荷斯坦牛乳硬质干酪的抗氧化特性比较[J].食品科学, 2020, 41(15):15-21.
YANG J, LIANG Q, SONG X M, et al.Comparison of antioxidant properties between yak milk and Holstein cow milk hard cheese[J].Food Science, 2020, 41(15):15-21.
[10] 巨玉佳, 梁琪, 张炎, 等.电子鼻联合GC-MS分析不同牦牛乳干酪中特征挥发性成分[J].食品与机械, 2014, 30(4):14-17.
JU Y J, LIANG Q, ZHANG Y, et al.Analysis of volatile components in yak milk cheese with GC-MS assisted by electronic nose technology[J].Food and Machinery, 2014, 30(4):14-17.
[11] ULBRICHT T L V, SOUTHGATE D A T.Coronary heart disease:Seven dietary factors[J].The Lancet, 1991, 338(8 773):985-992.
[12] TORKAMANI A E, JULIANO P, AJLOUNI S, et al.Impact of ultrasound treatment on lipid oxidation of Cheddar cheese whey[J].Ultrasonics Sonochemistry, 2014, 21(3):951-957.
[13] POTTIER J, FOCANT M, DEBIER C, et al.Effect of dietary vitamin E on rumen biohydrogenation pathways and milk fat depression in dairy cows fed high-fat diets[J].Journal of Dairy Science, 2006, 89(2):685-692.
[14] DROUIN G, GUILLOCHEAU E, CATHELINE D, et al.Impact of n-3 docosapentaenoic acid supplementation on fatty acid composition in rat differs depending upon tissues and is influenced by the presence of dairy lipids in the diet[J].Journal of Agricultural & Food Chemistry, 2018, 66(38):9 976-9 988.
[15] MÉNDEZ-CID F J, CENTENO J A, MARTÍNEZ S, et al.Changes in the chemical and physical characteristics of cow′s milk butter during storage:Effects of temperature and addition of salt[J].Journal of Food Composition and Analysis, 2017, 63:121-132.
[16] VLAEMINCK B, FIEVEZ V, CABRITA A R J, et al.Factors affecting odd- and branched-chain fatty acids in milk:A review[J].Animal Feed Science & Technology,2006, 131(3-4):389-417.
[17] KASUBUCHI M, HASEGAWA S, HIRAMATSU T, et al.Dietary gut microbial metabolites, short-chain fatty acids, and host metabolic regulation[J].Nutrients, 2015, 7(4):2 839-2 849.
[18] AMER B, NEBEL C, BERTRAM H C, et al.Novel method for quantification of individual free fatty acids in milk using an in-solution derivatisation approach and gas chromatography-mass spectrometry[J].International Dairy Journal, 2013, 32(2):199-203.
[19] COSSIGNANI L, GIUA L, URBANI E, et al.Fatty acid composition and CLA content in goat milk and cheese samples from Umbrian market[J].European Food Research & Technology, 2014, 239(6):905-911.
[20] AIGSTER A, SIMS C, STAPLES C, et al.Comparison of cheeses made from milk having normal and high oleic fatty acid compositions[J].Journal of Food Science, 2000, 65(5):920-924.
[21] ABID Y, AZABOU S, JRIDI M, et al.Storage stability of traditional Tunisian butter enriched with antioxidant extract from tomato processing by-products[J].Food Chemistry, 2017, 233:476-482.
[22] SIMOPOULOS A P.The importance of the omega-6/omega-3 fatty acid ratio in cardiovascular disease and other chronic diseases[J].Experimental Biology and Medicine, 2008, 233(6):674-688.
[23] DIEDRICH M, HENSCHEL K P.The natural occurrence of unusual fatty acids.Part 1.Odd numbered fatty acids[J].Molecular Nutrition & Food Research, 2010, 34(10):935-943.
[24] LANDS B.Measuring blood fatty acids as a surrogate indicator for coronary heart disease risk in population studies[J].World Review of Nutrition and Dietetics, 2009, 100:22-34.
[25] SIMOPOULOS A P.The importance of the ratio of omega-6/omega-3 essential fatty acids[J].Biomedicine & Pharmacotherapy, 2002, 56(8):365-379.
[26] JIANG Z Z, LIU Y N, ZHU Y, et al.Characteristic chromatographic fingerprint study of short-chain fatty acids in human milk, infant formula, pure milk and fermented milk by gas chromatography-mass spectrometry[J].International Journal of Food Sciences & Nutrition, 2016, 67(6):632-640.
[27] COLLOMB M, BüTIKOFER U, SIEBER R, et al.Conjugated linoleic acid and trans fatty acid composition of cows′ milk fat produced in lowlands and highlands[J].The Journal of Dairy Research, 2001, 68(3):519-523.
[28] ŠIMAT V, BOGDANOVIC′ T, POLJAK V, et al.Changes in fatty acid composition, atherogenic and thrombogenic health lipid indices and lipid stability of bogue (Boops boops Linnaeus, 1758) during storage on ice:Effect of fish farming activities[J].Journal of Food Composition and Analysis, 2015, 40:120-125.
[29] PENA-SERNA C, GOMEZ-RAMI B, ZAPATA-LOP N.Nutritional aspects of ghee based on lipid composition[J].Pakistan Journal of Nutrition, 2019, 18(12):1 107-1 114.
[30] CHEN S, BOBE G, ZIMMERMAN S, et al.Physical and sensory properties of dairy products from cows with various milk fatty acid compositions[J].Journal of Agricultural & Food Chemistry, 2004, 52(11):3 422-3 428.
