what is beer made of
How Beer is Made. Beer is made from four basic ingredients: Barley, water, hops and yeast. The basic idea is to extract the sugars from grains (usually barley) so that the yeast can turn it into alcohol and CO2, creating beer.t this point the brewing is complete and the fermentation begins. The beer is stored for a couple of weeks at room temperature (in the case of ales) or many many weeks at cold temperatures (in the case of lagers) while the yeast works its fermentation magic.