Malting Performance of a Millet Variety (Pennisetum maiwa) Grown at the Same Site During Different Growing Seasons

Abstract

The malting performance of a millet variety (Pennisetum maiwa) grown at the same site under similar conditions (similar fertilizer applications and nitrogen contents) during two seasons was studied. Although the millet samples were grown during different seasons, when the harvested samples were malted for 6 days both samples followed similar patterns of proteolysis and modification, producing similar levels of diastatic enzyme activity (measured as diastatic power). When the malted millet samples were mashed using the standard mashing method at 65�C, hot water extract recovery was suboptimal, but the release of total soluble nitrogen and free amino nitrogen (FAN) was adequate. However, when the malted millet samples were mashed using the decantation mashing method developed for extracting malt from cereals with a high gelatinization temperature (e.g., sorghum or maize), extract recovery, soluble nitrogen production, and FAN release were adequate for both millet samples. These results showed that millet malt can be extracted in a manner similar to sorghum, which is a well-established cereal used in brewing continental-type lager beers and ales. Millet, therefore, could fulfill a role similar to sorghum as a raw material for brewing. Most important, the marginal differences found in the parameters analyzed for malt produced from the same millet variety grown under similar conditions during different growing seasons suggest that the physiology of P. maiwa is reasonably consistent, which might lead to millet producing malt of consistent quality and character. Verification of this will require more investigation.