BREAKDOWN OF CRYSTAL-STRUCTURE IN POTATO STARCH DURING GELATINIZATION

Using a synchrotron source, in. situ small-and wide-angle X-ray studie s of the gelatinization of 40% potato starch slurries were carried out . By determining how the crystallinity index changes with temperature, it is possible to follow the destruction of the crystals. Fitting the (100) peak of the starch structure has shown that the crystals change only slightly in dimension over the temperature range studied. The la rge-scale swelling which occurs during gelatinization is associated wi th amorphous regions of the starch granule structure. (C) 1997 John Wi ley & Sons, Inc.