Influence of incorporation of peanut protein isolate on pasting, rheological and textural properties of rice starch.

This study investigated the influence of peanut protein isolate (PPI) incorporation in rice starch blends (RS-PPI) in terms of their rheological, textural, and microstructural properties. Among all fitted models in steady-state rheology, the Power-law model had the best fit. Incorporation of PPI improved storage modulus (G′) and loss modulus (G″) but decreased the limiting strain of the linear visco-elastic region. In the frequency sweep study, G′ and G″ increased with PPI addition for the samples containing high starch ratios, whereas the opposite trend was observed for the samples containing low starch ratios. The stress relaxation curves fitted reasonably well with the Peleg model (R2 > 0.995), and the initial and equilibrium force obtained followed the same trend as hardness values obtained from the TPA study. Initially, PPI addition to RS formed an interactive gel network showing honeycomb-like features, but further addition of PPI led to a formation of a non-homogeneous network. [Display omitted] • Pasting, rheological and textural properties of RS-PPI blends were studied. • RS-PPI blends exhibited shear thinning behavior and Power-law model showed the best fit. • Addition of PPI decreased the pasting properties of RS-PPI blends. • The Peleg model fitted the stress relaxation data reasonably well. • RS-PPI composite gels exhibited honeycomb-like features and segregation of protein and starch occurred at higher PPI ratio. [ABSTRACT FROM AUTHOR]