不同氧化条件下葵花籽油脂肪酸含量与低场核磁共振弛豫特性的相关性  

The Correlation between Fatty Acids and LF-NMR Relaxation Properties in Sunflower Oil during Different Oxidation Processes

作　　者：夏义苗 王欣[1] 陈利华[1] 毛锐[1] 黄远芬 刘宝林[1] Xia Yimiao;Wang Xin;Chen Lihua;Mao Rui;Huang Yuanfen;Liu Baolin(Institute of Food Safety and Quality,University of Shanghai for Science and Technology,Shanghai 200093;College of Food Science and Engineering,Henan University of Technology,Zhengzhou 450001)

机构地区：[1]上海理工大学食品质量与安全研究所,上海200093 [2]河南工业大学粮油食品学院,郑州450001

出　　处：《中国食品学报》2018年第7期286-294,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金青年科学基金项目(NS FC31201365);上海市科委重点攻关项目(11142200403);上海市教委科研创新项目(11YZ109)

摘　　要：为探讨油脂在不同氧化过程中脂肪酸含量与其相应低场核磁共振弛豫信号间的相关性,分别收集葵花籽油在不同氧化温度(105℃和180℃)条件下的脂肪酸组成和弛豫特性(T_(21),S_(21),T_(22),S_(22),T_(23),S_(23),T_(2w)),并应用主成分回归分析建立基于低场核磁共振弛豫特性的脂肪酸含量的预测模型,进行外部验证。结果表明:新鲜葵花籽油主要包含亚油酸(63.80%)、油酸(29.48%)、棕榈酸(5.73%)、亚麻酸(0.54%)和山嵛酸(0.43%);不同氧化过程中,亚油酸含量均显著降低,油酸和棕榈酸含量则均升高,亚麻酸和山嵛酸变化不明显,最终引起油样不饱和度整体下降;油样全氧化值呈增大趋势,且与其不饱和度和T2w呈一定相关性;对105℃和180℃氧化葵花籽油弛豫特性分别提取2和3个主成分,前者只有油酸预测良好(R2=0.93),外部验证结果欠佳(R2=0.54),后者棕榈酸、油酸和亚油酸预测模型相关系数均高达0.96以上,且验证可靠(R2>0.94),这说明低场核磁共振技术在深度氧化葵花籽油脂肪酸组成检测方面具有一定的应用潜力。The fatty acid composition and LF-NMR relaxation properties（T21, S21, T22, S22, T23, S23, T2w） of sunflower oil during different oxidation processes（105 ℃ and 180 ℃） were collected and studied separately to analyze the correlationship between them. Then the regression model based on LF-NMR relaxation properties was built to forecast the certain fatty acid composition in sunflower oil. At last, blind samples were applied to validate the satisfactory of the proposed model built before. The results indicated that the fresh sunflower oil was mainly composed of linoleic acid（63.80%）, oleic acid（29.48%）, palmitic acid（5.73%）, linolenic acid（0.54%） and behenic acid（0.43%）. The content of linoleic acid reduced significantly while oleic acid and palmitic acid raised, additionally, linolenic acid and behenic acid fluctuated during different oxidation processes. As a result, the unsaturation degree（MUFA/SFA and PUFA/SFA） of oils decreased along with the extension of oxidation time. Moreover, the total oxidation value（TV） increased overall and was related to the unsaturation degree and T2 wto some extent. 2 and 3 principal components were obtained separately fromLF-NMR relaxation properties for 105 ℃ and 180 ℃ correspondingly. During 105 ℃, only the oleic acid prediction model was conducted successfully（R2=0.93）, whereas it failed to validation（R2=0.54）. In the case of 180 ℃,both prediction model（R2〉0.96） for palmitic acid, oleic acid and linoleic acid and their verification（R2〉0.94） were accurate. Therefore, it was remarkable that the LF-NMR technology possessed certain potential in detecting the major fatty acids content of sunflower oil undergoing advanced oxidation process.

关 键 词：葵花籽油 氧化 低场核磁共振 脂肪酸 弛豫特性 

分 类 号：TS225.15[轻工技术与工程—粮食、油脂及植物蛋白工程]