The action mechanism of annealing temperatures after rapid cooling of mung bean starch-based drinking straws

Abstract

To reveal the impact of annealing temperature on the condensed structure of mung bean starch-based drinking straws, the rapidly cooled drinking straws were annealed at different temperatures. The structural and functional characteristics of annealed drinking straws were analyzed. The results revealed that the interactions between hydrogen bonds in the drinking straws weakened as annealing temperature increased from 70 °C to 90 °C. However, the interactions increased as annealing temperature continued to increase to 130 °C. The relative crystallinity, fracture strength in bending, elastic modulus in bending, and gelatinization enthalpy decreased initially and then increased as annealing temperatures increased. This research confirmed that the influence of annealing temperature on the condensed matter structure of drinking straws was a complex process. The outcomes would provide new ideas for improving the properties of macromolecule-based materials such as starch, cellulose and proteins.