Evaluation of the potential use of millet as a substitute for barely in beer brewing

Abstract

In this project, fermentation was utilized to determine the alcohol content in millet at its optimum germination temperature basing on the hypothesis that starch containing substances yield ethanol and carbon dioxide after their sugar constituents undergo anaerobic decomposition by microorganisms. The main objective of this project was to determine whether millet has the required amount of alcohol that makes it a close substitute of barley in beer brewing industry. The project was carried out on a laboratory scale by soaking different masses of millet (intervals of 100g) in water for 24 hours and later the water was drained allowing the grain to germinate and the process stopped by drying. The germinated millet was crushed and the flour was mixed with water and boiled to form a dark brown porridge and after cooled to a temperature of 40°C and yeast was added to the solution which was fermented for three days without testing for yeast effectiveness and the product distilled and tested. The Lucas test showed that the product contained a primary alcohol, the iodoform test showed that the alcohol contained a methyl group attached on the carbon atom containing the functional group and the boiling point measurement indicated that the product was ethanol however more sophisticated method such as spectroscopic method can also be employed however this research relied more on the boiling point. Within the limited laboratory facilities, 23ml of the ethanol was obtained from 100g of millet on average and with sophisticated equipment a larger percentage of alcohol could be obtained. Due to the lower germination time, higher nutrition value and high yield of ethanol per mass made millet better substitute for barley in beer brewing.