ABSTRACT
At room temperature, starch granules will contain some water (for potato starch, up to 0.5 g/g starch when dispersed in water), with the amount depending on the relative humidity at which they are stored and the type of starch. On heating, granules will take up water, resulting in a volume increase by 30-40%. Some of the amylose may leach from the granules. At higher temperatures, melting of the semicrystalline region will take place although entanglement of the amylopectin chains will persist. With increasing temperature, much stronger swelling of the granule will take place to several times their original size. Moreover, phase separation of the amylose and amylopectin will occur, resulting in leaching out of virtually all amylose. At still higher temperatures, the swollen granules are broken up into far smaller fragments, the extent of which depends on temperature and the application of shear
forces. At T below 100°C and without appreciable shear forces, the granules will maintain their integrity.
