Abstract:

In order to facilitate the development and utilization of waste beer yeast resource, trehalose was extracted from waste beer yeast by microwave extraction processing. The optimal extraction processing parameters were explored by single factor and orthogonal polynomial regression experiments. Results indicated that a regression model for trehalose extraction was Y=3.672+0.00142Z12 － 0.0297Z1+0.00187Z3 (where, Z1, microwave treatment time; Z2, liquid-solid ratio; Z3, microwave power). The optimal extraction conditions were liquid-solid ratio of 40:1, microwave power of 500 W, microwave treatment time of 25 min, and microwave treatment temperature of 80 ℃. Under the optimal extraction conditions, the extraction rate of trehalose could reach up to 5.07%. Compared with microwave-assisted and ultrasound-assisted methods, microwave treatment has less yield of trehalose; however, microwave extraction time was only 1/9 of microwave-assisted extraction method, and 1/15 of ultrasound-assisted extraction method.

Key words: microwave, waste beer yeast cell, trehalose, orthogonal polynomial, regression model