PROTEIN‐STARCH EXTRACTION AND NUTRITIVE VALUE OF THE BLACK‐EYED PEA (Vigna sinensis) AND ITS PROTEIN CONCENTRATES

Two processes were developed for the preparation of protein concentrates with a concommitant recuperation of the starch fraction from the Black‐eyed pea ( Vigna sinensis ). The first was a one‐stage extraction process using a 4:100 peeled meal:soivent ratio, a pH of 9.0, and 25°C, and the second a two‐stage process of 1 hr per stage using a peeled meal:solvent ratio of 12:100, pH of the suspension 6.8, and 25°C. Protein extraction efficiencies of 87 and 86% for the one and two‐stage processes, respectively, were not improved by increasing either extraction time or temperature (up to 50°C). The starch recuperation was 84% in the former and 76% in the latter. Both protein concentrates (66–70% protein) obtained by isoelectric point precipitation proved to have a higher methionine and cystine content and a higher PER value than the original peeled meal Preliminary results indicate the suitability of the protein concentrates for use in the formulation of pasta products, sausages and tacos.