Structure of Starch from Mango Seed

Starch was isolated from fresh mango seed kernels. The effect of glucoamylase‐α‐amylase on the granule ultrastructure was evaluated by scanning electron microscope. Amylose and amylopectin were isolated and their molecular structures were studied, using enzymic methods, HPTLC, and gel permeation chromatography. The structure of amylopectin was similar to amylopectin of other starches. The shortest branch chain had 6 glucose units. Amylose had a ß‐amylolysis limit of 77%. In order to improve solution stability during debranching with pullulanase and chromatography, amylose was partially acetylated. The debranchin of the unmodified and modified amyloses produced a 15–25% decline in the limiting viscositiy number and a slight shift in the molecular size distribution. These results are consistent with the concept that a fraction of the amylose molecules have limited branching and that these branched chains contain a significant number of glucose units.