Characterization of non-linear rheological behavior of SPI-FG dispersions using LAOS tests and FT rheology
- Authors: Bi, Chonghao , Li, Dong , Wang, Li-jun , Wang, Yong , Adhikari, Benu
- Date: 2013
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 92, no. 2 (2013), p. 1151-1158
- Full Text: false
- Reviewed:
- Description: The effect of flaxseed gum (FG) on the rheological and nonlinear stress response behaviors of mixed soy protein isolate (SPI)-flaxseed gum (FG) dispersions were studied. Results showed that the viscosity of the SPI-FG mixed dispersions increased significantly with increase in the FG concentration. Both the shear stress and the apparent viscosity values as a function of shear rate were fitted well using Power law model as expected. The frequency dependence of G′, G′′ and tan δ of soy protein isolate decreased as the FG concentration increased. The large amplitude oscillatory shear (LAOS) test and Fourier transform (FT) rheology analysis showed that the addition of flaxseed gum strongly affected the structure of the SPI-FG mixed dispersion system as shown by deformation of the nonlinear stress response curve and significantly altered magnitude of higher harmonic curve. The addition of FG increased the instantaneous strain softening effect of the SPI-FG mixed dispersion system. © 2012 Elsevier Ltd.
- Description: 2003011034
Viscoelastic properties and fractal analysis of acid-induced SPI gels at different ionic strength
- Authors: Bi, Chonghao , Li, Dong , Wang, Li-jun , Adhikari, Benu
- Date: 2013
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 92, no. 1 (January 2013), p. 98-105
- Full Text: false
- Reviewed:
- Description: The viscoelastic property and scaling behavior of acid (glucono-delta-lactone)-induced soy protein isolate (SPI) gels were investigated at various ionic strengths (0-800 mM) and five protein concentrations ranging between 4% and 8% (w/w). The infinite storage modulus (G '(infinity)) and the gelation start time (t(g))which indicate the progress of gelation process exhibited strong ionic strength dependence. The storage modulus and critical strain were found to exhibit a power-law relationship with protein concentration. Rheological analysis and confocal laser scanning microscopy (CLSM) analysis were applied to estimate the fractal dimensions (D-f) of the gels and the values were found to vary between 2.319 and 2.729. The comparison of the rheological methods and the CLSM image analysis method showed that the Shih, Shih, Kim, Liu, and Aksay (1990) model was better suited in estimating the D-f value of acid-induced SPI gel system. (C) 2012 Elsevier Ltd. All rights reserved.
- Description: C1