Abstract: A comparative analysis of fatty acid contents between ultra-high temperature (UHT) milk and reconstituted milk was carried out using 1H nuclear magnetic resonance (1H NMR) spectroscopy. The results showed that the relative contents of linolenic acid, linoleic acid, oleic acid and saturated fatty acid in UHT milk and reconstituted milk were (0.98 ± 0.11)% and (0.90 ± 0.04)%, (1.15 ± 0.36)% and (1.11 ± 0.36)%, (27.30 ± 0.56)% and (26.78 ± 0.78)%, and (43.26 ± 1.56)% and (43.81 ± 2.34)%, respectively. Orthogonal partial least squares discriminant (OPLS-DA) analysis and independent sample t test were performed on the 1H NMR spectrum peaks and fatty acid contents of the two milks. It was found that the relative content of linolenic acid was significantly different (P < 0.05) between the two milks. Nutritional assessment showed that UHT milk was more suitable than reconstituted milk for people with hyperlipidemia and/or high cholesterol, while the nutritional value of other fatty acids was similar between both milks.

Key words: ultra-high temperature milk, reconstituted milk, processing technology, fatty acid, 1H nuclear magnetic resonance

摘要： 以超高温灭菌乳和复原乳为研究对象，利用1H核磁共振（nuclear magnetic resonance，1H NMR）技术对2 种乳中脂肪酸含量进行分析。结果表明：超高温灭菌乳和复原乳中亚麻酸相对含量分别为（0.98±0.11）%、（0.90±0.04）%，亚油酸相对含量分别为（1.15±0.36）%、（1.11±0.36）%，油酸相对含量分别为（27.30±0.56）%、（26.78±0.78）%，饱和脂肪酸相对含量分别为（43.26±1.56）%、（43.81±2.34）%；对2 种牛乳脂肪酸的1H NMR谱峰和脂肪酸含量进行正交偏最小二乘法判别分析和独立样本t检验，发现亚麻酸相对含量在2 种牛乳间具有显著性差异（P＜0.05），并根据结果对2 种乳进行营养学评价，对高血脂、高胆固醇等人群而言，超高温灭菌乳比复原乳更合适，2 种乳中其他脂肪酸的营养价值相近。

关键词: 超高温灭菌乳, 复原乳, 加工工艺, 脂肪酸, 核磁共振氢谱