月桂叶油树脂的提取及呈香物质分析

采用正交试验法优化月桂叶油树脂超临界CO2萃取工艺条件，用气相色谱-质谱（gas chromatography-mass spectrometry，GC-MS）联用技术和电子鼻技术分析鉴定超临界萃取、水蒸气蒸馏以及乙醇萃取所得油树脂差异。结果表明：超临界CO2萃取的最佳条件为萃取压力22 MPa、萃取温度50 ℃、萃取时间2 h，此条件下月桂叶油树脂得率平均为2.12%。经GC-MS分析，超临界CO2萃取所得油树脂鉴定出致香成分66 种，主要成分为乙酸松油脂（20.38%）、1,8-桉油醇（19.88%）、木香烃内酯（5.61%）、丁香酚甲醚（3.41%）、芳樟醇（2.57%）等；水蒸气蒸馏所得油树脂鉴定出的致香成分为42 种，其中主要成分为1,8-桉油醇（20.99%）、乙酸松油脂（19.34%）、丁香酚甲醚（2.56%）、去氢夙毛菊内酯（2.36%）、α-松油醇（2.17%）等；乙醇萃取所得油树脂鉴定出的致香成分为24 种，主要成分为1,8-桉油醇（15.33%）、4-蒈烯（10.75%）、乙酸松油脂（10.22%）、去氢夙毛菊内酯（10.09%）、木香烃内酯（2.62%）等。由电子鼻主成分分析与雷达图谱可以看出，不同的提取工艺所得到的月桂叶油树脂致香成分差异较大。

Extraction and Aroma Composition of Laurel Leaf Oleoresin

An orthogonal array design was used to optimize the process conditions for supercritical CO2 extraction of laurel leaf oleoresin. Gas chromatography-mass spectrometry (GC-MS) and electronic nose (E-nose) were used to identify the differences in aroma composition among laurel leaf oleoresins extracted with supercritical CO2, steam distillation and ethanol. The optimal conditions for supercritical CO2 extraction were determined as follows: extraction pressure, 22 MPa; temperature, 50 ℃, and time, 2 h. Under these conditions, the average yield of laurel leaf oleoresin was 2.12%. GC-MS analysis revealed that a total of 66 aroma compounds were identified from supercritical CO2-extracted laurel leaf oleoresin, mainly including terpinyl acetate (20.38%), 1,8-cineole (19.88%), costunolide (5.61%), methyleugenol (3.41%), and linalool (2.57%), 42 volatile aroma compounds were identified from laurel leaf oleoresin extracted by steam distillation, consisting mainly of 1,8-cineole (20.99%), terpinyl acetate (19.34%), methyleugenol (2.56%), dehydrosaussurealactone (2.36%), and α-terpineol (2.17%), and ethanol-laurel leaf oleoresin were found to contain 24 aroma components, mainly 1,8-cineole (15.33%), 4-carene (10.75%), terpinyl acetate (10.22%), dehydrosaussurealactone (10.09%), and costunolide (2.62%). The principal component analysis (PCA) and radar plots of E-nose data revealed that laurel leaf oleoresins extracted by demonstrated considerable differences in aroma composition.