Rheological properties of modified soy protein isolates emulsions

, PUPPO, M.C; SORGENTINI, D.A; AÑON, MARÍA CRISTINA

JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY (JAOCS)

SPRINGER

Lugar: Berlin; Año: 2003 vol. 80 p. 605 - 611

0003-021X

The feasibility of replacing common emulsifierswith soy protein isolates (SPI) in low-calorie salad dressings wasevaluated. Structural modifications of SPI were obtained by thermal-acidic treatment with or without neutralization (TH1.6N andTH1.6, respectively). Modification of flow properties of TH1.6and TH1.6N emulsions by thermal treatment and different protein concentrations was evaluated through shear stress vs. shearrate measurements in a rotational viscometer. TH1.6N isolatesgenerated emulsions with higher shear stress and apparent viscosity than those prepared with TH1.6. Heated TH1.6N emulsions at 10% protein gave the highest values of shear stress andplastic flow behavior. These emulsions had high consistency, viscosity, and elasticity. TH1.6N isolates had lower emulsifyingcapacity than TH1.6, probably due to the higher protein aggregation produced during neutralization, which prevented protein unfolding. These isolates would be suitable for the preparation ofstable emulsions with adequate consistency and elasticity