提取方法对紫云英籽油脂肪酸组成及氧化稳定性的影响

分别采用微波-超声协同提取法(MUAE)、超声辅助法(UAE)和溶剂提取法(SE)提取紫云英籽油,通过测定紫云英籽油的出油率、理化特性、脂肪酸组成和氧化稳定性对3种提取方法进行比较。结果表明:溶剂提取法的籽油出油率最高,为32.01%。3种方法提取的籽油的颜色、密度、折光率、苯并(α)芘差异不明显,但酸值、过氧化值和碘值存在差异,其中溶剂提取法的酸价和过氧化值最高,超声辅助法的碘值最高。3种方法提取的籽油,在饱和脂肪酸和不饱和脂肪酸的总量上无明显差异,但对脂肪酸组分含量有影响,其中溶剂提取法的油酸和亚油酸含量最高,超声辅助法的亚麻酸含量最高。3种方法提取的籽油氧化均遵循一级化学反应,溶剂提取法的籽油氧化稳定性最好,超声辅助法的氧化稳定性最差。综合评定紫云英籽油油品及其脂肪酸成分,用超声辅助法提取并低温储存油品较好。

The effect of Extraction Method on Fatty Acid Composition and Oxidative Stability of Astragalus sinicus Seed Oil

Microwave-ultrasound synergistic extraction (MUAE), ultrasound-assisted extraction (UAE) and solvent extraction (SE) were used to extract astragalus sinicus seed oil. The oil yield, physicochemical properties, fatty acid composition and oxidation stability of astragalus sinicus seed oil were determined and compared. The results showed that the highest oil yield was 32.01% by solvent extraction. The color, density, refractive index and benzo (a) pyrene of seed oil extracted by the three methods had no significant difference, but the acid value, peroxide value and iodine value were different. The acid value and peroxide value of solvent extraction method were the highest, and the iodine value of ultrasound-assisted method was the highest. There was no significant difference in the total content of saturated fatty acid and unsaturated fatty acid among the three methods, but the content of fatty acid components was affected. The content of oleic acid and linoleic acid in solvent extraction method was the highest, and the content of linolenic acid in ultrasound-assisted method was the highest. The oxidation of seed oil extracted by three methods followed the first-order chemical reaction. The oxidation stability of seed oil extracted by solvent method was the best, and that of ultrasonic-assisted method was the worst. The oil and fatty acid composition of astragalus sinicus seed oil were comprehensively evaluated. It was better to extract by ultrasound-assisted method and store the oil at low temperature.