Micronizing treatment of wheat germ and optimization of extraction technology for wheat germ protein

Defatted wheat germ was micronized by comibmed method of hammer mill and colloid mill in order to increase the extraction rate of protein, followed by steps of alkali extraction and ultrafilter concentration, respectively. A quadratic mathematical model was developed statistically by means of Box-Behnken central composite design (CCD) and response surface methodology (RSM). Consequently, the optimized processing parameters were determined, including particle sizes of 23 μm, pH value of 9.5 and temperature of 51℃. The extraction rate can reach 68.6% under optimized conditions. The results show that micronization a helpful treatment to improve the extraction rate of defatted wheat germ protein.