PERSPECTIVE :Here is, in a nutshell, what brewing is all about. The following is Appendix II from Martyn Cornell's excellent book Beer: the Story of the Pint.
Beer: The Story of the Pint is the chronicle of britain's favourite drink, a river that stretches back from the sacred hallucinogenic beers of the Stone Age farmers, the double beer that cheered the Tudors and Stuarts, the porter of the eighteeth-century London, the Victorian IPAs, and forward to today's designer lagers.
The brewer's mission
The brewer's mission is to take his raw material, grain (normally barley, sometimes wheat, very occasionally oats or rye), and convert the starch in the grain into sugar. Then he turns the sugar into alcohol, with the help of yeast. This makes his job more difficult, and more technically challenging, than the task of the wineŽmaker, who has only to crush the grapes to ler the yeast on the grape skins attack the sugars in the grape juice. The job of turning grain starches into sugars is known as malting. The grain is soaked, which tricks it into starting to sprout. As it sprouts, enzymes in each barleycorn or wheat seed turn the starch inside the grain into sugar that the grain will use as fuel to power its growth. The maltster's art lies in halting that growth with heat, at just the point where the enzyme activity is at its height but not too much starch has been used up by the growing grain. How hot the maltster makes the grain, and how long he roasts it, will have a major effect on the flavour and colour of the final beer.The semi-sprouted, dried grain, now known as malt, is roughly ground by the brewer and mixed with hot water to form a porridge. This process, known as mashing, starts up the enzymes in the grain again, and more starch is converted into sugar. The malt sugar dissolves in the hot water, and this hot, sweet liquid, known as wort, is then drained off.
Modern brewers will then boil the wort with hops, to add a bitter flavour and a preservative effect to the final beer; in the millennia before hops, brewers might add other herbal flavourings. Then comes the final stage: introducing yeast to the wort. The yeast, a single-cell organism, feeds by turning the sugar into alcohol and carbon dioxide. Once the yeast has finished its job, and converted all the sugar it can (normally after six or seven days), the liquid, which is by now. beer, can be racked into casks. It is then stored for a while - the time varies, depending on what type of beer it is - before being drunk.
The brewery at Queen's College, Oxford, pictured in 1927. The brewer, J.F. Hunt, who was about to retire after 56 years, is seen by the mash run holding the mashing rake or mash fork.
Next he is seen by the copper, holding the handle of the sixteenth-century lead-and-wood pump that lifts the wort from the underback.
Finally he is down in the cellar topping up still-fermenring casks from a coopered filling can.
Martyn Cornell, Beer: The Story of the Pint. The History of Britain's Most Popular Drink, Headline Book Publishing (2003), 320 pages.