微波预处理对山苍子油脂肪酸组成、活性成分 及挥发性风味的影响Effect of microwave pretreatment on fatty acid composition, active components and volatile flavor of Litsea cubeba oil

旨在为山苍子油的高效加工和深度开发利用提供参考，以未经微波预处理的山苍子果为对照，对山苍子果进行微波预处理，考察微波预处理时间对压榨山苍子油得率、脂肪酸组成、活性成分和DPPH自由基清除率的影响，并对比分析挥发性风味成分的差异。结果表明：微波预处理能有效提高山苍子油得率，且对山苍子油的脂肪酸组成无影响；山苍子油总酚含量在10.48～13.06 mg/g之间，与对照组相比，微波预处理组山苍子油的总酚含量上升了3.25%～24.62%；微波预处理组山苍子油的角鲨烯、α-生育酚和β-谷甾醇含量均显著高于对照组，其中角鲨烯含量随微波预处理时间的延长而增加，而α-生育酚和β-谷甾醇含量先增加后下降；微波预处理组山苍子油的DPPH自由基清除率均高于对照组，且随着微波预处理时间的延长呈现先升高后降低的趋势；山苍子油中共鉴定出23种挥发性化合物，包括萜烯类11种、醛类4种、醇类3种、酮类1种、其他4种，与对照组相比，微波预处理组柠檬烯含量增加，月桂烯和柠檬醛含量降低；随着微波预处理时间的延长，山苍子油整体风味由浓郁的柠檬香转变为柑橘柠檬香。综上，适度微波预处理可以提高山苍子油的品质。To provide reference for the efficient processing and deep development utilization of Litsea cubeba oil, with Litsea cubeba fruit without microwave pretreatment as control, the Litsea cubeba fruit was pretreated with microware, and the effects of microwave pretreatment time on the oil yield, fatty acid composition, active components and DPPH free radical scavenging rate of pressed Litsea cubeba oil were studied, and the differences of volatile flavor components were compared and analyzed.The results showed that microwave pretreatment could effectively improve the yield of Litsea cubeba oil, and had no effect on the fatty acid composition. The total phenol contents of Litsea cubeba oil ranged from 10.48 mg/g to 13.06 mg/g. Compared with the control group, the total phenol contents of Litsea cubeba oil in microwave pretreatment group increased by 3.25%-24.62%.The contents of squalene, α-tocopherol and β-sitosterol in the microwave pretreatment group were significantly higher than those in the control group, and the content of squalene increased with the prolonging of microwave pretreatment time, while the content of α-tocopherol and β-sitosterol first increased and then decreased. The DPPH free radical scavenging rate of Litsea cubeba oil in microwave pretreatment group was higher than that in control group, and the DPPH free radical scavenging rate increased first and then decreased with the prolonging of microwave pretreatment time. A total of 23 volatile compounds were identified in Litsea cubeba oil, including 11 terpenes, 4 aldehydes, 3 alcohols, 1 ketone and 4 others. Compared with the control group, the content of limonene increased in microwave pretreatment group, and the contents of myrcene and citral decreased. With the prolonging of microwave pretreatment time, the overall flavor of Litsea cubeba oil changed from rich lemon aroma to citrus lemon aroma. In conclusion, moderate microwave pretreatment can improve the quality of Litsea cubeba oil.