Optimization of extraction process of crude protein from grape seeds by RSM

Grape seed is a potential source of edible protein, so effective extraction of protein component from grape seed seems to be very important. However, so far, such information is unavailable. In this study, the conditions for protein extraction from the grape seeds were optimized by the single factor test and the response surface methodology (RSM). A box-behnken design (BBD) was used for experimental design and analysis of the results to obtain the optimal extraction conditions. Solvent/meal ratio, extraction temperature, pH and extraction time were found to have a significant effect on the protein yield. From the single factor test, the optimal range of extraction conditions was obtained. Based on the RSM analysis, optimum extraction parameters were obtained as following: solvent/meal ratio 22.5/1 (v/w), extraction temperature 35°C, pH 9.8, and extraction time 29 min. Under the optimized conditions, the experimental values were in good agreement with those predicted by the model. These results help design the process of optimal protein extraction from grape seeds for future use in food industry.