Thermo-reversibility of short-chain glucan aggregates (SCGA) derived from various starches

Thermo-reversibility of short-chain glucan aggregates (SCGA) prepared from eight kinds of starches was investigated. All native SCGA showed the double helical melting transition between 70 and 105 °C. Upon immediate cooling after heating, the SCGA was recrystallized at 50 °C. The double helical melting temperature and enthalpy of all recrystallized SCGA were increased compared to native SCGA, indicating improved thermal stability of recrystallized SCGA. The morphology of recrystallized SCGA was similar to native SCGA with discrete particle shape and decreased the continuous phase cluster. Additionally, the crystallinity, thermal properties, and in-vitro digestibility of recrystallized SCGA were greatly affected by the heating temperature. Boiling (100 °C) showed higher relative crystallinity but lower double helical melting and resistant starch content compared to autoclaving (121 °C), suggesting that the remaining crystal seeds affected the re-assembly of short-chain glucans during the recrystallization. The physicochemical properties of SCGA would be controlled through its thermo-reversibility and heating temperature.