基于UPLC-Q-TOF-MS技术分析原料乳冷藏过程中脂类代谢组学  

Lipidomic Analysis of Raw Milk during Refrigerated Storage Using Ultra-high Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry

作　　者：李璞钰 剧柠[1] 罗玉龙 王媛媛[1] 苟萌 LI Puyu;JU Ning;LUO Yulong;WANG Yuanyuan;GOU Meng(College of Food and Wine,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学食品与葡萄酒学院,宁夏银川750021

出　　处：《食品科学》2021年第20期120-127,共8页Food Science

基　　金：国家自然科学基金地区科学基金项目(31760479);宁夏自治区重大专项(KJT-201701)。

摘　　要：为探究4℃冷藏过程中原料乳脂类物质的变化,以酸价及过氧化值为衡量标准判定原料乳的脂肪氧化情况;采用超高效液相色谱-四极杆串联飞行时间质谱技术对各冷藏阶段脂类代谢物的差异及变化进行分析。结果显示,冷藏过程中原料乳酸价及过氧化值持续升高,其中0~1 d升高速度最快。差异代谢物分析显示,乳代谢体系变化极为复杂,脂类代谢物种类及变化在所检测的6类显著性差异代谢物中最突出,从初始的9种增至24种。进一步分析脂类代谢物表达量时发现游离脂肪酸、磷脂表达量分别在冷藏3~4 d和冷藏6 d会发生较大波动。结合KEGG通路分析,发现游离脂肪酸参与的脂肪酸生物合成在各冷藏阶段变化显著(P<0.05);冷藏3 d时脂类代谢物通路数量最多,共计9条。因此,冷藏3 d可作为原料乳冷藏品质控制的关键节点。In order to explore the change of lipids in raw milk during cold storage at 4 ℃, acid value(AV) and peroxide value(PV) were measured to determine the degree of fat oxidation in raw milk. Ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used to analyze the differences and changes of lipid metabolites during cold storage. The results showed that both AV and PV continued to increase during 6 days of cold storage, and the rate of increase was the fastest from day 0 to day 1. The analysis of differential metabolites showed that the changes of the metabolic system in raw milk were very complicated, and the types and changes of lipid metabolites were the most prominent among the six significantly differential metabolites identified. The number of lipid metabolites increased from 9 to 24. Further analysis found that the expression levels of free fatty acids and phospholipids fluctuated greatly on day 3 to 4 and day 6, respectively. Based on these results combined with KEGG pathway analysis, it was found that fatty acid biosynthesis in which free fatty acids are involved changed significantly during cold storage(P <0.05). On day 3, the most lipid metabolism pathways(9) were identified. Therefore, the third day of cold storage could be seen as the key point for quality control of raw milk.

关 键 词：原料乳 冷藏 脂类代谢物 代谢组学 

分 类 号：TS252.2[轻工技术与工程—农产品加工及贮藏工程]