Comparative studies on properties of amylases extracted from kilned and unkilned malted sorghum and corn

This study investigated the activities of a-amylase, β-amylase and glucoamylase extracted from kilned and unkilned sorghum and corn. Dry grains of sorghum and corn were obtained, steeped and allowed to undergo malting at room temperature for 48 h. Part of the malted starch was kilned by taken into an oven at 50°C for 24 h while the other part was derootted by hand before further processing. a-amylase, β-amylase and glucoamylase were extracted from the kilned and unkilned malted cereals and assayed. Results obtained showed that sorghum is richer in amylases than corn. The activities of the three enzymes were higher in unkilned malt than kilned malt which indicates an appreciable loss in enzymes activities during kilning. The cereals are also rich in glucoamylase compared to the other two enzymes. All the enzymes have appreciable glucose yield on maltose substrate. These results demonstrated that sorghum and corn are good sources of amylases which are the basic enzymes required for hydrolysis of starch to glucose in many industrial processes most especially in brewing. Key words: Amylase, sorghum, corn, kilned malt, unkilned malt.