Grain alcohol or fermented alcohol, also known as rectified spirit, uses yeast to ferment grain materials containing starch and carbohydrate to produce. Its chemical term is ethanol.
What is grain alcohol?
What is grain alcohol made from?
Its production process includes saccharification, fermentation, filtration, sterilization, etc. Grains used as raw material can be sorghum, corn, rice, batata, potatoes, rye or wheat, though you can also use fruits or even just sugar.
How is grain alcohol made?
In the brewing process, starch absorbs water and swells and heats to gelatinize to form a starch with a loose structure, which is decomposed into low-molecular monosaccharides under the action of amylase. Monosaccharides are decomposed under the catalysis of decarboxylase and dehydrogenase, and gradually decompose to form carbon dioxide and alcohol. Brewing with starch as raw material requires two main processes, one is the starch saccharification process, and the other is the alcohol fermentation process.
1. The saccharified starch of starch is hydrolyzed into monosaccharides under the action of the catalyst amylase. Amylase is derived from microorganisms in koji, and the reaction process is shown in the figure:
2. Alcohol-fermented starch is converted into glucose under the action of amylase, and glucose is converted into alcohol under the action of alcoholic enzyme, which is secreted by yeast. Most distiller's yeast also contains yeast (except gluten yeast). The reaction process is as follows:
This reaction formula was first proposed by French chemist Guy Lussac in 1810. Later, scientists studied and measured that theoretically 51.149 alcohol can be produced per 1009 glucose (the actual output is lower than the theoretical one). In 1857, another French chemist, Louis Pasteur, discovered that alcohol fermentation was carried out in the absence of oxygen. For this reason, he made the famous thesis that "fermentation is life activity without air".