High pressure/temperature pasting and gelling of starch related to multilevel structure-analyzed with RVA 4800.

ABSTRACT

This paper evaluated the relationship between multi-scale structure and high-pressure gelation properties of nine types of starches with different amylose (AM) content and crystalline polymorphic structure by RVA 4800. Higher average chain lengths of long amylopectin (AP) chains (DP > 36) and AM content, and lower relative content of short AP chains (DP ≤ 36) contributed to the higher peak temperature and peak time at 95-140 °C, and lower peak viscosity, through viscosity, and final viscosity at 95-110 °C. Rheological and texture parameters including storage modulus, loss modulus, hardness, and gumminess, had no significant correlation with starch structural parameters at 95-120 °C, but were instead controlled by AM molecular structure at 130-140 °C. AM content was mainly responsible for the rheological behaviors of starch gels at 130-140 °C, and short and intermediate AM chains were mainly associated with the texture of starch gels at the temperature ranges.