Biochemical composition, bioactivity, processing, and food applications of winged bean (Psophocarpus tetragonolobus): A review

Abstract

The winged bean, Psophocarpus tetragonolobus (L.) D.C., is called the four-angled bean or Goa bean, which is an underutilized, non-conventional, and multipurpose tropical legume cultivated in Southeast Asia and Papua New Guinea. The objective of this article was to reveal a comprehensive view on the nutritional properties, biochemical compositions, health benefits, processing, and food applications of winged beans. The average moisture, carbohydrate, protein, fat, crude fiber, and ash content of 138 genotypes of winged bean seeds were found as 9.09 ± 1.73%, 26.81 ± 6.88%, 34.98 ± 4.63%, 18.01 ± 2.27%, 10.24 ± 5.49%, and 4.16 ± 0.41%, respectively. Leaves of winged beans are good sources of vitamins such as vitamin C (14.5–128 mg/100 g), thiamine, riboflavin, niacin, vitamin B₆, folate, vitamin A (5240–20,800 IU), and vitamin E. The seed of winged beans is rich in calcium, iron, phosphorus, zinc, and copper. The anti-nutritional factors, namely, trypsin inhibitor, chymotrypsin inhibitor, phytic acid, saponin, tannin, oxalate, and flatulence saccharides of winged bean, were reported to be in the range of 40–99.5 TIU/mg of protein, 86.4–109.6 CIU/mg of protein, 4.09%–9.96%, 0.6%, 0.77%–0.97%, 0.5%, and 0.04%–0.18%, respectively. This bean can prevent diabetes, cancer, and asthma, boost immunity, and promote women's and men's reproductive health. Winged are transformed into consumable form by processing methods such as soaking, cooking, sprouting, fermentation, roasting, and so forth. This bean is processed into traditional products (curries, soup, pickles, etc.) and contemporary products (milk, tofu, tempeh, etc.). Future research should focus on promoting its utilization as an alternative to soybeans toward meeting global food and nutritional security.