Comparisons of functional properties of protein isolate and protein concentrate in Plukenetia volubilis L.seeds

Plukenetia volubilis L.protein isolate ( PPI) and protein concentrate ( PPC) were prepared using the alkaline extraction and acid precipitation method and the impurity separating technology respectively. Solubility, oil and water holding capacities, foaming property and viscosity of PPI and PPC were studied.Results revealed that oil and water holding capacities and foaming property of PPC were better than PPI, while PPI had higher solubility and viscosity.Solubility of both PPI and PPC decreased with increasing pH from 2 to 4, but increased with pH value from4 to 12.Viscosities of PPI and PPC decreased with elevating temperature. Oil- holding capacities of PPI and PPC reached the maximum at 50℃ with the values of 154.37% and 294.70% respectively.