BUCKWHEAT STARCH (Fagopyrum esculentum): AQUEOUS EXTRACTION, MODIFICATION BY HMT AND CHARACTERIZATION

Buckwheat (Fagopyrum esculentum) is a pseudoceral. It grains are nutritionally rich and boast great technological potential for use in the food industry in infant and backed food as well as ingredient of functional products. Flour is considered as an alternative to celiacs because it does not contain gluten. It is an option for the growing appeal for a healthy diet, as well as containing starch as a major component. Starches in native form have restricted use in the industry. So modifications are made to increase their application. These modifications can be chemical or physical. Physical modification is preferable and accepted by consumers. Heat-moisture treatment (HMT) consists of heating starch above gelatinization point with insufficient moisture (<35%). The main objective was extract buckwheat starch, modify by HMT and assess its physico-chemical, thermal and morphological properties. The starch granules from buckwheat have spherical or polygonal shape, with an average size around 1 - 7.5 mu m. Morphology of buckwheat starch granules was not altered. The XRD technique showed no signifficative differences between main peaks in diffractograms however the relative crystallinity decrease. DSC analysis allowed to observe that according HMT the enthalpy decrease and gelatinization occurs in higher temperatures.