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.