Abstract:

A YJYⅡ-type cold press machine was modified and used for extraction of wheat germ oil from full-fat wheat. Pressure chamber temperature was controlled by taking measures such as cooling water injecting into the axis direction, etc. Response surface methodology based on a four-variable, five-level quadratic rotation-orthogonal combination design was employed to investigate the pairwise interaction effects of water content of the material, pressure chamber temperature and extraction pressure on vitamin E content of wheat germ oil. Results showed that the optimal values of the above parameters were determined as follows: water content of the material 7%, pressure chamber temperature 75 ℃ and extraction pressure 3.6 MPa. The product obtained under such conditions contained 268.7 mg of vitamin E /100 g and 925 mg of phospholipids of /100 g, with an extraction yield of 32%.

Key words: wheat germ oil, cooling water, strip row, cold-pressed extraction, vitamin E, phospholipids