【作者】 汪学德； 李晓栋； 刘日兵；

【Author】 WANG Xuede;LI xiaodong;LUI ribin;School of Food Science and Technology,Henan University of Technology;

【机构】 河南工业大学粮油食品学院；

【摘要】 传统水代法和热榨法可制得具有浓郁的香味及氧化稳定性好的特色芝麻油脂,但出油率均低于80.00%。水代法萃取时间长,制得的油脂色泽深,芝麻渣中水分干燥和后处理困难,环境污染指数高。低温超临界、亚临界萃取法芝麻油的出油率高,所得芝麻油色泽浅,芝麻木酚素（芝麻素、芝麻林素）含量较高。亚临界萃取法芝麻油提取率远高于超临界,提高萃取温度、延长萃取时间、增加萃取次数及增加料液比,有利于芝麻油的提取。亚临界丁烷萃取芝麻油的适宜条件为:料液比1∶4/g·mL^-1,萃取5次,萃取温度50℃,萃取时间30min,压力0.8 MPa,此条件下芝麻油提取率可达95.60%。较高温亚临界萃取对芝麻油和木酚素的选择性一致。低温亚临界萃取对芝麻素和芝麻林素有更好的选择性,萃取10 min时芝麻油中芝麻素和芝麻林素含量达到最高,提取率分别为92.12%、95.62%,所得芝麻油氧化诱导时间长,氧化稳定性好。电镜观察了芝麻籽粒萃取前后的形态,萃取前籽粒大小不一、厚薄不匀,呈不规整形态。5次萃取后芝麻籽粒变成尺寸大小更接近、多孔的形态,说明亚临界条件下的流体有较好的破碎、孔化作用,提高了固-液接触面积和提取率。更多还原

【Abstract】 Traditional aqueous extraction and hot pressing methods can produce featured sesame oil with strong aroma and oxidation stability. but their oil yield rates are lower than 80%. For the aqueous extraction method, the extraction time is very long, the color of sesame oil is much dark,and it is more trouble to dry the moisture out of or to dispose of the sesame dregs, so causing environmental pollution index is high. By means of supercritical or subcritical extraction at low temperature, the sesame oil yield efficiency is higher, and oil color is light, also sesame lignans（sesamin and sesamolin） content is higher. Comparing with the supercritical extraction, the sesame oil yield of subcritical extraction is much higher, and to raise extraction temperature, prolong extraction time and increase extraction times as well as reduce the ratio of solid to liquid, it is conducive to the extraction of sesame oil. The suitable conditions of subcritical butane extraction for sesame oil are: material liquid ratio 1:4/g·mL^-1 extraction 5 times, extraction temperature at 50℃, extraction time 30 min, extraction pressure at 0.8 MPa. Under these extraction conditions,the sesame oil extraction rate can reach at 95.60%. Using subcritical extraction at higher temperature to extract sesame oil and sesame lignans, it has consistent selectivity; while, at lower temperature the subcritical extraction has better selectivity to sesamin and sesamolin. Oil yield as well as contents of sesamin and sesamolin in the extracted oil will be significantly decreased along with extraction time prolonging. The contents of sesamin and sesamolin in the extracted sesame oil reach at the highest level when extraction time is 10 min, the extraction rates were 92.12% and 95.62% respectively. Sesame oil extracted is of long oxidation induction time with good oxidation stability. Observing through electron microscopy, the morphology of sesame seed before to be extracted, it appears no uniform grain size, uneven thickness and irregular shape; After being subcritical extracted times, it emerges approximate grain size, porous morphology. This fact indicates that, under the conditions of subcritical extraction, the fluid has better functions of fragmentation and penetrations, it increases the solid-liquid contacting area and improves extraction yield.更多还原