Exploring characteristics of waxy wheat starches cross-linked at low levels: Insights from pasting, rheological, and textural properties

Abstract

The objective of this work was to understand the cross-linked waxy wheat starch (WWS) characteristics from thermal properties, pasting properties, and paste rheological behaviors, textural properties, morphology, and freeze-thaw stability. WWS, waxy maize starch (WMS), and waxy tapioca starch (WTS) were cross-linked using sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP) with a ratio of 99:1 (w/w) at levels of 0.01%, 0.05%, and 0.1%. WWS had lower gelatinization temperatures and enthalpy change than WMS and WTS, and cross linking had no or little impact on them. With increasing cross-linking levels from 0.01% to 0.1%, the peak viscosity decreased for the WWS, but increased for WMS and WTS, indicating that WWS was more sensitive to STMP/STPP. Cross-linking led to a substantial increase in final viscosity for all waxy starches. WWS cross-linked at 0.05% had the highest final viscosity among three waxy starches cross-linked at all three levels, which was consistent with the highest firmness, consistency, and cohesiveness of the paste and the morphology of swollen granules. Paste from WWS at 0.1% cross-linking showed almost no thixotropy, while all cross-linked WMS and WTS pastes exhibited high thixotropy. WWS had lower syneresis than WMS and WTS before and after cross linking, indicating a better cold storage stability.