Starch Gelatinisation and Retrogradation

Both amylose and amylopectin take part in the retrogradation process, and network structure formation and up to four different steps of ordering have been postulated [30]. The first one, which takes place within a few hours, has been ascribed to gelation 

The fourth step involves the phase separation of water (syneresis) due to excessive retrogradation of the starch chains [30-33]. 

These two peaks are denoted as Gr and Mit and are correlated with the G and Mi peaks in the gelatinisation phenomenon. Gr and Mir are mainly due to amylopectin, which after the gelatinisation process, can rebuild its structure under appropriate time-temperature conditions giving rise to new thermal transitions close to the original ones [34]. Gr and Mir are detectable both in normal starches and in waxy (high amylopectin content) starches (in this case Gr and Mir are more pronounced) [34,35]. 

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