Cereal Chem 50:395 - 403.  |  VIEW ARTICLE
Effect of Processing pH on the Properties of Peanut Protein Isolates and Oil.

K. C. Rhee, C. M. Cater, and K. F. Mattil. Copyright 1973 by the American Association of Cereal Chemists, Inc. 

Peanut protein isolates and oil were prepared from raw peanuts using an aqueous system at several different pH values for protein extraction and precipitation. Some of their physical and chemical properties, as well as the extent of their recoveries, were determined in order to compare the effects of pH during preparation of isolates on the quality and yield of the products. The maximum recoveries of both protein and oil from raw peanuts were obtained at pH 8.0, and extraction pH values higher than 8.0 considerably reduced the protein solubility of the isolates with no significant increases in the recovery of the proteins. Higher pH values also increased the loss of oil through saponification. All four isolates remained stable when heated; no protein coagulation occurred even if isolates were heated at 95 C. for 30 min. Solution viscosities were quite low at all protein concentrations as compared to other vegetable proteins, and the pH of extraction and precipitation of the isolate significantly influenced viscosity characteristics.