Beer consist for the biggest part of water. Though, water is not everywhere the same, the hardness and acidity of water can influence the taste of beer. Because of differences depending on the place and the way the water is purified the water can differ significantly. Nowadays, thanks to modern water treatments it is possible to adjust water according to own needs. Back in the days beers where more regionally located, because of the uniqueness and quality of the water in that area.
Most beers are brewed with help of barley. Barley contains many enzymes which are essential in beer brewing. Often brewers also make use of other raw materials like corn, rice, oats, rye and of course wheat. This could be because of a cheaper price, as is the case with rice and corn or because the material contains special characteristics. For example oats forms a better filter bed, which makes the filter process more efficient and wheat produces a fruity wheat flavor and a nice layer of foam.
Barley is being converted into malt, which happens in a malt house where the natural grow process of the barley is being manipulated. To start the germination process of the barley, water and oxygen are essential. The barley are rotationally being soaked and dried to adopt oxygen. Slowly the barley seed starts to produce small roots. During the grow enzymes are being created by the barley to feed the little seed with sugar. At this moment the germination process of the seed is stopped by kilning the barley. The malt undergoes all kind of changes in color, smell and taste. This is why differences in malt appear. Some sorts of malt are being roasted to give them certain flavors. Last, the little roots of the germs are being removed and the malt is ready to go to the brewery.