Studies on Optimization of Peanut Protein Isolate Production by Alkaline Extraction and Acid Precipitation

Peanut protein isolate was prepared through alkali extraction and acid precipitation. The extraction process was optimized by single factor and orthogonal experiments,and the most suitable process conditions for extracting peanut protein isolate were determined as follows: extraction temperature 60℃,ratio of material and liquid 1∶9,pH 9.0 and extraction time 90 min,pH 4.5 was preferable for the precipitation of peanut protein isolate. 42.5% protein was extracted from peanut protein isolate and the purity of the isolated protein was 95.65%.