3种制油工艺对油茶籽油品质的影响Effects of three oil production processes on the quality of camellia seed oils

为优选出功能营养与氧化稳定性兼顾的油茶籽油制备工艺，以油茶籽仁为原料，采用超临界CO2萃取法、湿法和热榨法制备油茶籽油，并测定其基本理化指标、活性成分含量、脂肪酸组成和氧化稳定性，以评价3种制油工艺对油茶籽油品质的影响。结果表明：湿法制备的油茶籽油的酸值（KOH）和过氧化值较超临界CO2萃取法和热榨法低，分别为0.63 mg/g和0.14 g/100 g；湿法制备的油茶籽油的生育酚含量最高；超临界CO2萃取法制备的油茶籽油的角鲨烯、β-谷甾醇、类胡萝卜素和多酚含量均最高，其中角鲨烯、β-谷甾醇、类胡萝卜素含量分别为热榨法的1.36、1.74倍和1.38倍；热榨法制备的油茶籽油中饱和脂肪酸含量低于湿法与超临界CO2萃取法，但脂肪酸组成无显著差异；湿法制备的油茶籽油的氧化诱导时间最长，运用外推法计算出25 ℃下其氧化诱导时间为1 037 h。综上，湿法制备的油茶籽油氧化稳定性最佳，超临界CO2萃取法制备的油茶籽油活性成分保留率总体最高，适合功能性油脂生产，热榨法满足油茶籽油传统风味需求，可根据产品需求选择合适的制油工艺。 To select an optimal preparation process of camellia seed oils that balances functional nutrients and oxidative stability, with camellia seed kernel as the material, camellia seed oils were extracted by supercritical CO2 extraction, wet extraction, and hot pressing. Their basic physicochemical indicators, active component content, fatty acid composition, and oxidative stability were determined to evaluate the effects of the three oil production processes on the quality of camellia seed oils. The results showed that the acid value and peroxide value of camellia seed oil prepared by wet extraction were lower than those obtained by supercritical CO2 extraction and hot pressing, at 0.63 mgKOH/g and 0.14 g/100 g, respectively. The camellia seed oil prepared by wet extraction had the highest tocopherol content. The camellia seed oil prepared by supercritical CO2 extraction had the highest contents of squalene, β-sitosterol, carotenoids, and polyphenols. Specifically, the contents of squalene, β-sitosterol, and carotenoids in the oil obtained by supercritical CO2 extraction were 1.36, 1.74 times, and 1.38 times those in the oil obtained by hot pressing, respectively. The saturated fatty acid content in camellia seed oil prepared by hot pressing was lower than that in the oils obtained by wet extraction and supercritical CO2 extraction, but there was no significant difference in fatty acid composition. The camellia seed oil prepared by wet extraction had the longest oxidation induction time. Using the extrapolation method, its oxidation induction time at 25 ℃ was calculated to be 1 037 h. In conclusion, camellia seed oil prepared by wet extraction exhibits the best stability, camellia seed oil prepared by supercritical CO2 extraction generally has the highest retention rate of active components, and the oil prepared by hot pressing meets the demand for traditional flavor of camellia seed oil. The appropriate oil production process can be selected according to product requirements.