Study on electrostatic complexation between soy protein isolate and sugar beet pectin

Electrostatic complexation between soy protein isolate (SPI) and sugar beet pectin (SBP) were induced by in situ acidification using glucono-δ-lactone (GDL) .The formation of electrostatic complexes and their structural evolution were monitored at different SPI /SBP ratios by measuring light scattering intensity and turbidity of the mixtures during acidification using dynamic light scattering and UV/Vis spectrophotometer respectively.The results showed that SPI and SBP could form molecular complexes of different structures and stabilities, depending on pH and SPI/SBP ratio.Those complexes included intramolecular soluble complex, intermolecular soluble complex, and intermolecular insoluble complex.The investigation enabled the establishment of a detailed phase diagram for the electrostatic complexation of SPI and SBP.