Effect of heat-moisture treatment on the thermal, structural and morphological properties of Quinoa starch
Raphael Lucas Jacinto Almeida, Newton Carlos Santos, João Vítor Fonseca Feitoza, Gabriel Monteiro da Silva, Cecília Elisa de Sousa Muniz, Raphael da Silva Eduardo, Victor Herbert de Alcântara Ribeiro, Virgínia Mirtes de Alcântara Silva, Mércia Melo de Almeida Mota
Abstract
The aim of this study was to investigate the effects of heat-moisture treatment (HMT) on the thermal, structural and morphological properties of quinoa starch native to Brazil (QSB). To assess the influence of HMT, the QSB with 20% moisture was heated (110 °C) at different times (1 h (HMT1), 2 h (HMT2) and 3 h (HMT3)) in an electric oven. Process temperature during HMT influenced gelatinization temperatures and enthalpy, making the starch more resistant to thermal processes. Different intensities were observed in the FTIR, however no new functional groups were noticed. XRD indicated a type A semi-crystalline material, with relative crystallinity ranging from 19.36 to 23.75%. Through SEM, irregular shapes with characteristics similar to the polygonal shape and with the appearance of cracks were observed, with a diameter that varied from 134.04 to 187.23 µm. To conclude, the biggest changes were observed after 3 h of the process (HTM3), being the most adequate time to modify the QSB.