Malt




	History Barley is regarded as the oldest cultivated cereal, with its origins somewhere between 10,000 and 5,000 B.C. There are examples of Sumerian barley dated at c.2000 B.C. in the British Museum. During the middle ages, right up to the end of the nineteenth century, safe drinking water was scarce, and a safe way of drinking was to brew beer. Most of this beer was brewed at home, and so there would almost certainly have been a maltings in every village. The use of barley as the main cereal used for brewing, was due to the passing of an Act by Edward II in 1315 that, "beer should be made from grain other than wheat" as so much wheat was being malted for brewing, that there was a serious risk of famine in the country. Grain Structure A barley grain is basically made up of two parts: the outer, or 'aleurone' layer which contains proteins, surrounding the centre of the grain known as the endosperm. The endosperm consists mainly of starch, and it is this which is converted into sugars, a process started during malting, and completed in the mash tun. back to top Malting Process The malting process can be divided into three basic stages: steeping, germination, and kilning. The malting process described below is that of traditional floor-malting. Steeping The barley grains are placed into large tanks, known as cisterns or steeps, containing water. The grains soak up the water, until they have absorbed enough to begin germination. The point at which the grain is deemed ready to be removed from the steep is determined by the maltster's experience and judgement. Germination After steeping, the barley is laid out on a floor at depth of about 5 inches, and allowed to germinate. Germination causes heat to be created, and carbon dioxide as a by-product of respiration. The grains are maintained between 15'C and 20'C. The evolved heat of the germination must be dissipated, and this is done by turning the barley twice a day. This also helps disentangle the growing shoots, and so avoid the bed of grains becoming a solid mass. It is during germination that enzymes are created, and the process of converting the starchy endosperm begins. The enzymes break down proteins in the aleurone layer, so leaving the starch exposed. It is this exposed starch which is converted into sugars during mashing. The maltster judges when to stop the germination process, and the barley, now known as Green Malt, goes on to its final stage: kilning. Kilning The kilning stage dries the green malt thereby completely halting germination, and provides colour to the grain. The varying colours and flavours of malt are created by differing temperatures and lengths of kilning. back to top Malt Types There are three type of brewer's grains: kilned (fully-malted), crystallised, and roast grains. The following list is some of the types of malt available but many more are used. Lager Malt Kilned at a low temperature, so giving a very pale colour. Colour: 3 EBC Pale Malt Kilned at a low temperature for a longer period than Lager Malt, it is pale in colour and is the primary ingredient of British beers. Colour: 5 EBC Amber Malt Produced by lightly roasting Mild Ale or Chocolate Malt, which reduces the harsh flavours of higher-coloured roasted grains. Amber malt has a pleasant dry, biscuity flavour, and can provide a rounded flavour without having too much effect on the colour or sweetness of a beer. Colour: 40 - 60 EBC back to top Crystal Malt This is the most widely used coloured malt in Britain. As well as providing colour to a beer, crystal malt contributes greatly to a beer's flavour, offering flavours such as nutty, malty, caramel, biscuity, and toffee. Crystal malt contains a high amount of dextrins and other non-fermentable sugars, and so aids in giving a beer an amount of body. There are also indications that crystal malt contributes to head retention, and can increase a beer's shelf life by as much as 50%. Crystal malt is produced from green malt, and is described as a 'crystallised' malt. The starch in crystal malt has already been converted to sugars, and so does need to be mashed during brewing - it can just as easily be added to the boil. It is usual, though, to place it in the mash tun with the rest of the grist. Colour: 75 - 300 EBC Chocolate Malt Produced by roasting malt that has been kilned to lager malt colour, at a high temperature (230'C). Used for stouts, porters, and other dark beers. 1000 - 1200 EBC Roasted Barley Roasted barley is produced by roasting raw, unmalted barley at very high temperatures for about 2 1/2 hours, until it is burnt. During the final part of the roasting, the grains are very close to combustion, and close supervision by the maltster is required. Roasted barley is primarily used in the brewing of stouts. It readily contributes to head formation and retention. Colour: 1200 - 1500 EBC back to top