Storage time of 2 and 4 weeks was selected for observing retrogradation of starch, since all samples exhibited very low amylose content. Values of ∆Hret of starch gels after storage for 2 and 4 weeks are summarized in Table 2. ∆Hret for all starches increased with increasing storage duration. ∆Hret for the 20 waxy starches varied from 0.9 J/g (WR12) to 6.4 J/g (BW) and 5.1 J/g (TKW5) to 10.1 J/g (BW) after 2 and 4 weeks of storage, respectively.
Sasaki and Matsuki (1998) indicated that longer chains of amylopectin formed more stable crystallites and more regions of crystallinity during storage. Thus, the difference between retrogradation values of 2 weeks and 4 weeks could have been influenced by amylopectin branched chains, and the effect of amylopectin short chains on recrystallization perfection during storage