Porous starch was produced by digestion of freeze-dried potato starch with alfa-amylase from Bacillus sp. The surface structure of the granules became perforated and in the interior of the granules a capsule-like cavity was formed, i.e. the hydrolyzed starch can be used as an encapsulant. The structure change of the granules was observed with confocal laser scanning microscopy and scanning electron microscopy. The degree of starch hydrolysis could be correlated with the Avrami equation. The activation energy of starch hydrolysis by alfa-amylase was 83 kJ/mol.
- starch granule