Brewing beer is a process of converting grain starch into sugars and then fermenting the wort. Barley grains are soaked in water for a short period of time, just enough to germinate. The process is stopped by drying the grains, which are then broken to reveal the germinated seed inside. This is known as malt, and it is the term used by brewers to refer to germinated and dried barley.
Starch is a large molecule carbohydrate used in brewing beer, and it is necessary for any alcoholic beverage as it provides sugar for yeast to ferment. Plants produce glucose, a sugar, during photosynthesis, but they need to store it until needed. To do this, they bind several glucose molecules into fewer, larger molecules, which reduces the amount of water entering the cell and makes its storage much less demanding. This largest molecule is called starch. The basic ingredients of beer are water and a source of fermentable starch, such as malted barley.
Most beer is fermented with brewer's yeast and seasoned with hops. Less commonly used sources of starch include millet, sorghum and cassava. Secondary sources (supplements), such as corn (corn), rice, or sugar, can also be used, sometimes to reduce costs or to add a feature, such as adding wheat to help retain beer foam. To make beer, grain starch breaks down into sugars to create wort, which is then fermented into beer. The most common source of starch is ground cereal or semolina; the proportion of starch or cereal ingredients in a beer recipe can be called ground, peak grain, or simply puree ingredients.
In brewing, starch from malted barley (and sometimes from other sources) is degraded in mash. The sugars formed in mash by starch degradation are fermentable by brewer's yeast, while some of the larger carbohydrates are not. By altering the temperature, pH and time of the mash or performing a staggered puree, a brewer can potentially alter the yield of his extract, the fermentability of the must and influence other variables. To better understand how these things can be achieved, it is useful to know as much as possible about starch. Grains (barley, wheat, rice, corn, oats, rye etc.) must undergo a malting process before they can be used to make beer (others don't).The malting process simulates grain germination which metabolizes the grain's natural sugars (called maltose), which is what yeast feeds on during fermentation.
To do this, the seed is soaked in water until the plant starts to grow. Just before it emerges from the seed it is put in an oven and dried. The drying method can make different colors and flavors of malt. Most cultivated barley strains (known as local varieties) worked better as spring crops than winter crops and until the 1960s most malting in Europe was done with double-row spring barley. Wild barley probably originated in and around the Fertile Crescent and most varieties of Hordeum vulgare spontaneum are still found there. Sour beers such as lambicas are fermented entirely in wood while other beers are aged in barrels that were previously used to mature wines or spirits.
Filters that use a powdered medium are considerably more complicated to operate but can filter much more beer before regeneration. When hops are boiled alpha acid undergoes some chemical changes that allow it to make beer bitter. Although it is used in different proportions depending on the style being brewed ALL beer is made of grains hops yeast and water. It is produced by malting grain which creates enzymes that convert grain starches into fermentable sugars in the process. Barley growers have kept good breeding records for the past century or two so the pedigrees of many of these cultivars are well known. The sheets are placed in a filter frame disinfected (with boiling water for example) and then used to filter beer. During the 20th century barley breeders continued to use their knowledge of classical genetics to facilitate breeding in a tedious and laborious process. These are alpha- and beta-amylase which among them are capable of hydrolyzing much of the starch present in sugars not more than three glucose units in length.
