More than 90% of beer is water. Small wonder then that the breweries place high requirements on the quality of the water used. Breweries generally get their water from a well or spring, or they use tap water. There are many salts and minerals in the water, the quantity and variety of which affect the ultimate flavour of the beer.
The minerals in the water will also influence the head formation.
Malt is the sugar to be fermented that comes from the grain. Barley is generally used, although sometimes wheat and occasionally oats or spelt. Inferior raw materials for malts are maize and rice. Japanese Saké is made from rice (some people classify saké as a beer). Grain cannot ferment by itself. When the grain is left in water, allowed to germinate and then dried, fermentable sugar is released. This procedure is called malting. Barley malt is by far the most important sugar-containing raw material for producing beer. Only malted barley can be used in the brewing process. Wheat on the other hand can be used in both the malted and unmalted form for beer production. Wheat is used in the so-called wheat beers, including white beer and lambic.
In addition to the malted grain, sugar is often also added to help the fermentation.