Waxy maize starch amylolysis catalyzed by -amylase from Bacillus licheniformis was studied in terms of the quantitative evolution of the hydrolysis reaction, as well as in terms of morphological and crystallinity characteristics of partially hydrolyzed starch granules. The two methods used to determine reaction kinetics showed a change of reaction rate at approximately 6 h of reaction, delimiting two hydrolysis stages which have previously been attributed to the hydrolysis of starch regions with different crystallinity.Besides, for the mentioned hydrolysis time, the use of two different methods for CI calculation showed a maximum of crystallinity in residual starch granules. Scanning microscopy images illustrated the pattern of -amylase action over starch granules, with the most interesting feature being the generation of clear layered hydrolyzed/non-hydrolyzed interior structures, which suggested different susceptibility to enzyme attack of alternating growth rings. Image analysis allowed finding very good estimations of the growth rings thicknesses which agreed with values found in the literature.All three type of analysis performed herein (kinetic data, SEM and XRD analysis), contributed to the validation of the hypothesis that under the assay conditions chosen, in the initial hours of reaction amylolysis effectively proceeds preferentially and at a higher rate in the less ordered regions of starch. Moreover, results showedthat if reaction is stopped at 6 h of hydrolysis, micrometric starchgranules with increased crystallinity obtained by a pure enzymaticprotocol can be easily produced