Mechanisms of retarding the deterioration of pasted starch by curdlan during frozen storage

Abstract

This study analyzed the structural and property alterations of starch in frozen cooked noodles (FCNs) and developed a starch-curdlan model system to clarify curdlan's mechanism in slowing pasted starch deterioration during frozen storage. The results showed that the addition of 0.5% curdlan mitigated the increase in pasting viscosity and gelatinization temperature of starch in FCNs. This may be related to curdlan's ability to reduce amylose dissolution caused by ice crystals during frozen storage and hinder the rearrangement of amylopectin. As frozen storage time increases, the G′ of starch decreases and the G″ increases, which may be attributed to the increase in relative crystallinity and short-range ordering of starch. However, the addition of curdlan mitigates this trend. Moreover, incorporating 0.5% curdlan slows the increase in relative crystallinity (52.61%) and the decrease in the full width at half maximum (FWHM) (3.63%) of starch, thereby improving its microstructure. This study comprehensively elucidates the mechanism by which curdlan improves the quality of FCNs from the perspective of starch.