Modification of Starches with Different Amylose/Amylopectin Ratios Using the Dual Approach with Hydroxypropylation and Subsequent Acid-Thinning: II. Impacts on Gelatinization and Solution Properties

Abstract

Starches with different amylose (AM)/amylopectin (AP) ratios (waxy potato: WxPS; regular potato: PS; high AM corn: HACS) are hydroxypropylated (HP, two levels) and subsequently acid-thinned (AT) to produce dual-modified samples. The physicochemical characteristics and techno-functional properties of the solutions are investigated, and the data are evaluated statistically (analysis of variance). Differential scanning calorimetry gelatinization experiments reveal a reduction of the transition temperatures particularly due to HP. The subsequent AT decreases the specific enthalpy significantly. HACS samples have lower solubility (S) compared to their potato-based counterparts (WxPS and PS), but HP enhances the starch's S. The S of the AP of the HACS samples is comparatively high, and HP particularly facilitates the additional solubilization of AM. Dual-modified samples show characteristics of S similar to the corresponding HP samples. Or particular note, the HP-modified WxPS and PS, respectively, tend to cause molecular degradation of the polymers dissolved. The hot paste viscosity is impacted significantly by all varied factors.