The grains that are going to be used in a batch of beer are cracked in a process called Milling. This milling the grains makes it easier for them to absorb the water that they are mixed with and which extracts sugars from the malt.
Mashing converts the starches released during the malting stage, into sugars that can be fermented. The milled grain is dropped into hot water in a large vessel known as a mash tun. In this vessel, the grain and water are mixed together and heated to the correct temperature where enzymes in the barley malt convert the starches to sugars. The resulting sugar rich water is then strained out of the grans in a process known as lautering.
The liquid is known as wort and is moved into the brew kettle where it is boiled with hops and sometimes other ingredients such as herbs or sugars. The boiling process serves to terminate enzymatic processes, precipitate proteins, isomerize hop resins, and concentrate and sterilize the wort and lasts for 60 minutes or more. Hops added early in the boil give bitterness to balance the sweetness from the malt. Hops added close to the end of the boil add flavor and hops added right at the end or after the boil add aroma.
After the boil, the wort is quickly cooled and goes into a fermentation tank where the yeast is added or ‘pitched’ and fermentation begins.
After one to three weeks, the fresh beer is run off into conditioning tanks where they stay for a week to several months depending on the style. Adding hops during conditioning is called dry-hopping. Finally when the beer is ready, it may or may not be filtered depending on the brewery’s preference and then it is carbonated and moved to a holding tank until bottling or serving.