Physicochemical changes of starch during malting process of sorghum grain

The objective of this study was to evaluate the physicochemical changes that occur in sorghum starch during malting to determine its potential in the beer industry. The results showed that the physicochemical properties of amorphous amylose and amylopectin of starch over time are modified during the germination while its crystalline structure is not affected. During the different stages of malting the SEM images showed the progress of the enzymatic attack in the starch granule. Germination and the increase in reducing sugars supported amorphous starch degradation. The X-ray diffraction pattern confirmed that during malting, the crystalline structure in starch remained without changes. The pasting profile showed high values for peak and final viscosity, once the sorghum was soaked and decreasing over the malting process. These changes are associated with starch degradation and amylopectin debranching, increasing the reducing sugars.