Devitrification of the amorphous fractions of starch during gelatinisation

► Gelatinisation of waxy maize starch (WMS) in excess glycerol was investigated. ► A method was developed to reveal a “rigid amorphous” fraction in starch. ► Rigid amorphous fraction remained glassy in the presence of excess glycerol. ► Glass transitions of amorphous fractions (mobile and rigid) took place in two steps. ► Holding WMS in excess glycerol at 100 °C for 10 days did not gelatinise the whole WMS.