Introducing panda bean (Vigna umbellata (Thunb.) Ohwi et Ohashi) protein isolate as an alternative source of legume protein: Physicochemical, functional and nutritional characteristics

Panda bean protein isolate (PDPI), a legume-protein with Chinese characteristics, was investigated as an alternative potential food protein source. The physicochemical characteristics, functional properties and amino-acid composition of PDPI were determined and compared with soybean (SPI) and pea protein isolate (PPI). Results showed that PDPI was rich in phaseolin (mainly 7S vicilin), and its molecular weight was lower than that of SPI and PPI which were rich in legumin and vicilin. In comparison to SPI and PPI, PDPI showed the lowest solubility, surface-charge and surface-tension at pH 3.0, 7.0 and 9.0, but it exhibited comparable or even superior functionalities, especially in emulsifying and foaming abilities, gelling behaviour, rheological and textural properties. Moreover, the amino-acid composition and protein efficiency ratio of PDPI were excellent. The knowledge gained in the study is expected to provide reliable scientific science data for the potential application of PDPI in the food industry.