A major ingredient of most beers is malted barley.
Barley, a member of the grass family, is the fifth-largest cultivated cereal crop in the world and there are three varieties: 2-row, 4-row and 6-row, referring to the arrangement of the kernels around the shaft of the plant. 2-row is the main one used in brewing.
The malting process starts with the barley being steeped in water until it has absorbed almost half of it’s weight in water. The barley is then drained and partially germinated making the seed’s resources (starches) available for the brewer. If germination continued a plant would grow. The malster therefore gauges the germination carefully and stops the process by drying.
Malted barley is the main source of sugars (mainly maltose) that are fermented to produce the alcohol in beer and the basic light-coloured malts such as pale ale malt make up the bulk of the mix of malts in recipes.
There is a great variety of malts which involves the malt being kilned or roasted at different temperatures, moisture levels and durations to develop a range of colours and flavours. This gives the brewer options to create a range of interesting beer styles.