Pea and lentil protein extraction and functionality

These studies have demonstrated that peas and lentils can be used as protein sources for flours, concentrates and isolates. Less research attention has been devoted to lentil protein extraction, probably because of the greater cost of lentils as compared to peas. Pin-milling and air classification is well adapted to extracting pea flours to produce pea protein concentrates. Apparently, air-classification can be applied successfully to starch rich legumes, but will not give satisfactory results with lipid rich legumes. Wet processes, including alkaline and salt and acid solubilization, together with isoelectric precipitation or ultrafiltration, have been developed. The pea and lentil protein extracts of these processes exhibit comparable and complementary functionality to homologous soybean products. Air-classified pea protein concentrates are different from soy protein concentrates because of residual starch which can be useful for particular functional applications. Pea isolates appear to exhibit better foaming properties and more solubility than soy isolates, but pea isolates have to be more concentrated than soy isolates to produce viscous dispersions. The economic feasibility of pea and lentil protein extracts is related directly to protein content of the flour, unique functionality of the extracts, marketability of the by-products of extraction and the cost of peas or lentils. Presented at the 78th American Oil Chemists' Society Annual Meeting, May 17–21, 1987, New Orleans, LA.