Effect of the critical melting treatment on the short/long-term retrogradation behaviour of maize starch

Abstract

The shortand long-term retrogradation properties in normal maize starch (N-S) by critical melting treatment (CMT; including TO (onset temperature) melting (OM), TP (peak temperature) melting (PM), and TC (conclusion temperature) melting (CM)) were studied. Results indicated that CMT promoted short-term (1 day) and long-term (7 days) retrogradation of N-S in the following order: PM > CM > OM. After storage for 7 days, following the PM treatment, the gel hardness, the retrogradation degree, and relative crystallinity increased to 4.67 N, 13.191%, 8.58% from 2.87 N, 9.972%, and 6.20%, respectively. PM treatment resulted in harder starch granules, promoting the rearrangement of the starch crystalline structure during cold storage. This was confirmed by the increased storage modulus, decreased iodine blue value, reduced gap in the gel network, and compact aggregate formation. Results indicated that CMT can promote the retrogradation properties of N-S.