A novel strategy for preparing lignan-rich sesame oil from cold-pressed sesame seed cake by combining enzyme-assisted treatment and subcritical fluid extraction

Sesame cake is a by-product of cold-pressed sesame oil production. The residual oils and lignans in it have potential nutritional and economic value. If they can be extracted, the value of sesame cake is enhanced. In this study, enzyme-assisted treatment and subcritical fluid extraction were combined to recover lignan-rich oil from sesame cake, and the oils' qualities were comprehensively analyzed. The results showed that ME2, a multienzyme mixture of cellulase, pectinase, xylanase and beta-glucosidase, was effective in hydrolyzing cellular structure while also catalyzing the conversion of sesaminol triglucoside to sesaminol better than any of the enzyme combinations tested. Of the three subcritical fluids tested, dimethyl ether (DME) showed the best selectivity for bioactive compounds. ME2 and DME significantly increased the lignan and phenol content and oxidative stability of sesame oil. Using ME2 and DME to recover lignan-rich oil from sesame cake can enhance the economic value of cold-pressed sesame cake.