Molecular Structure of Banana Starch

Starch isolated from green banana fruit was hydrolyzed with pullulanase and β‐amylase and the hydrolyzates fractionated on Sephadex G‐50 and G‐100. Debranching of the starch and it β‐limit dextrin with pullulanase revealed that banana amylopectin had populations of d̄.p̄. 45 and d̄.p̄ 15 chains in a molar ratio of 1:6. The average chain length of the debranched starch and the debranched β‐limit dextrin was 26 and 10, respectively. The amylose content was 16%. Amylose prepared by selective leaching and by thymol complexation had β‐amylolysis limits ≥ 92%.