Effects pH and NaCl on the Protein Solubility, Emulsifying and Foaming Properties of Germinated and Ungerminated Melon (Colocynthis citrullus) Seed Flour

摘要

Defatted flour was prepared from germinated and ungerminated melon seeds. Protein solubility, foaming and emulsification capacities were measured over the pH range of 2.0 to 11.0 and NaCl concentrations of O. I M to I.O. M. Below and above pH 4, protein solubility increased reaching maximum values of 60% and 70% for ungerminated and germinated flour respectively at pH 10.5. The emulsification capacity versus pH profile and the foaming capacity versus pH profile showed close resemblance to the protein solubility versus pH curve suggesting that those properties depended on solubilized protein. Protein solubility of ungerminated and germinated flour was reduced at higher salt concentrations of 0.6M and0.8M respectively, which also altered the emulsifying and foaming properties. The germinated flour showed higher protein solubility, foaming and emulsification capacities than the ungerminated flour at all pH and NaCl levels, may be due to protein modification occurring during germination.