Enzymatic Extraction of Wheat Germ Oil

In this study enzymatic extraction of oil from wheat germ (WG) was investigated. Four enzymes (Viscozyme L, Multifect CX 13L, Multifect CX GC and Alcalase 2.4L FG) were screened for their efficacy to release oil from WG. Alcalase 2.4L FG treatment of WG improved oil extraction yield as compared to a control (aqueous extraction without enzyme). Alcalase 2.4L FG, which resulted in significantly higher oil yield than the other three enzymes, was chosen for optimization of the enzymatic oil extraction process by using Response Surface Methodology (RSM). Three processing parameters, liquid/solid ratio, extraction time and enzyme concentration, were investigated as the independent variables. Based on the experimental results, the highest oil yield, 66.5% (w/w), was obtained under the following conditions; liquid/solid ratio 16.5, enzyme concentration 1.1% and extraction time 19.25 h. A cubic model with R (2) of 0.91 was developed to describe the enzymatic extraction process. Although the cubic model predicted WG oil extraction yields well within the processing conditions studied in this study it was not effective beyond the experimental range. Further research focusing on high liquid/solid ratio, 16-20, and extraction time in 18-24 h and 0.5-5 h ranges is necessary to improve the model developed in this study.