Chemical and physicochemical properties of dried wet masa and dry masa flour

Commercial 'masas' and dry 'masa' flours (DMFs) were evaluated for chemical composition, water retention capacity (WRC), gelatinization, retrogradation and X-ray diffraction. Both masas and DMF had similar chemical compositions. The masas had higher soluble carbohydrate contents and lower WRCs than DMF. In the same way, DMFs had lower gelatinization temperatures and enthalpies of gelatinization than masas. These results were confirmed by X-ray diffraction analysis showing a lower degree of crystallinity in DMFs than in masas. The melting temperature in retrogradated samples of both masas and DMFs had a tendency to increase as storage time increased. This increment was more apparent with the enthalpy of melting. These results were probably associated with crystal perfection during starch retrogradation, ie recrystallization of gelatinized starch occurred as a time-dependent process. (C) 2003 Society of Chemical Industry.