棉籽油脂肪酸组成分析与评价

以收集于我国棉花主产区的82 份棉籽为实验材料，用全自动索氏浸提装置提取棉籽油，采用气相色谱-质谱联用仪和气相色谱仪对棉籽油脂肪酸组成进行定性和定量分析，探讨不同产地棉籽油脂肪酸组成的差异，并用主成分分析法对棉籽油的特征脂肪酸进行筛选。结果表明，棉籽仁出油率在18.84%～30.28%之间，平均出油率为24.95%。棉籽油中含有13 种脂肪酸，主要以亚油酸（51.99%～60.88%）、棕榈酸（18.30%～25.68%）和油酸（12.28%～18.50%）为主，其中不饱和脂肪酸占73.62%，多不饱和脂肪酸为亚油酸、亚麻酸占57.44%。除十七烷酸外，不同产地的棉籽油脂肪酸含量差异显著，并呈现明显的地域性。豆蔻酸、棕榈酸、棕榈油酸、硬脂酸、油酸、锦葵酸、亚油酸、苹婆酸、二氢苹婆酸和花生酸是棉籽油的特征脂肪酸。

Analysis and Evaluation of Fatty Acid Composition in Cottonseed Oil

A total of 82 cottonseed samples from several of the main cotton cultivating regions in China were used as experimental materials for the study. Cottonseed oil was extracted by an automatic Soxhelt extractor and the qualitative and quantitative analysis of fatty acid composition in the oil were done by gas chromatography-mass spectrometry (GC-MS) and gas chromatography (GC), respectively. The difference in the fatty acid composition of cottonseed oil from various regions was examined and principal component analysis (PCA) was applied to screen the characteristic fatty acids in cottonseed oil. The results showed that the average oil yield of cottonseed kernels was 24.95%, ranging from 18.84% to 30.28%. Thirteen fatty acids were identified and the main compounds were linoleic acid (51.99%–60.88%), palmitic acid (18.30%–25.68%), and oleic acid (12.28%–18.50%). Unsaturated fatty acids and essential fatty acids (linoleic acid and linolenic acid) accounted for 73.62% and 57.44% of the total fatty acids, respectively. Obvious differences in the contents of each fatty acid was found among different regions except heptadecanoic acid and it showed obvious regionality. Myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, malvalic acid, linoleic aicd, sterculic acid, dihydrosterculic acid and arachidic acid were the characteristic fatty acids in cottonseed oil.