Beer production. Grain and hot water are mixed in a barrel. The sweet porridge made of malt and water is called mash. It is very important to correctly determine the temperature during mixing in order to dissolve the necessary amount of sugar, to feed yeast for the future beer. During this process, the temperature and grain grinding grit determines the density and body of beer we will make, also whether beer will be sweet or dry, full bodied or watery, clear or cloudy. After dissolving sweet matter and lautering the grain (removing the fluid), the resulting product is called wort. It has to be boiled. Then, hops are added (and other flavourings, if used) and wort is transferred to the fermentation tanks. There, with the addition of yeast, fermentation takes place and the resulting beer is left for fermentation until it is in proper condition before bottling. Some types of beer are further matured in bottles.
Water. Making a good beer requires good water, and even small changes in the composition of water can lead to large differences in taste. For example, soft water gives softness and transparent body to beer and is particularly suited for lighter types of beer, such as pilsner or helles. Meanwhile, hard water gives a feeling of dryness, which emphasizes the bitterness of hops and malt, therefore it is perfect for IPA and stout beer. The most famous “beer cities” (such as Pilsen in the Czech Republic, with soft water, Bourton-on-Trent in England, with hard water, or Bend in the state of Oregon, which has fresh mountain water) are located in the vicinity of excellent water sources. In the city of Pilsen water naturally has been very soft and low in alkali, therefore local brewers have perfected the assimilation of the lightest local malt and bitterness of Saaz hops. Meanwhile, in the city of Dortmund water is richer in salts, especially calcium and bicarbonate ions, therefore allowing brewers to brew lager of richer taste.
Nowadays all breweries process water used for beer in one way or another. Some have special treatment facilities, others add different salts and/or minerals to water in order to balance the composition of water and make it more appropriate for the production of different beers. It will be different for top-fermented ale and for lower fermentation lager. If water is not specially prepared, then brewers are doomed to adapt to local environmental conditions and produce only one type of beer.
Grain/malt. Another important step in ensuring the quality of beer is taking care of malt quality. Water and grain provides the basis for beer, and final accents are later added by hops and yeast.
Malt is sprouted and roasted grain. The most common raw material for it is malting barley. Most preferred beer barley varieties are those rich in starch. During mixing, starch is converted to various forms of sugar: maltose, maltotriose, glucose, and others. These sweet wort substances feed the yeast during fermentation and produce carbon dioxide and alcohol. Malt also gives beer body and colour, therefore brewers make varieties by mixing different types of cereals and roasting malt to obtain different flavours. The more roasted malt, the darker the beer. Different malts provide different qualities to beer – oat gives the body strength, wheat gives excellent texture, rye adds depth and gives aftertaste of nuts, and rice and corn are used to improve the taste. Unmalted raw materials can also be used in the production of beer (up to 30% in Lithuania). Natural malt in small amounts can be used for taste, flavour or colour.
Hops. The character of beer is finally shaped with hops (as well as yeast). Hops grow all around the world, and each variety provides a different taste to beer – from citrus, tropical, herbal spice to the ground, grass, pine or floral aroma. From the same malt, using different hops one can make a completely different type of beer, for example, porter or Black India Pale Ale, tripel or the Belgian India Pale Ale. Hops work on beer just like spices on food – sometimes excellent beers are created by using a single type of hops, and sometimes their mixes and combinations are used for flavour and aroma (in the same way as spices). Incorrectly chosen hops may destroy the balance of flavour or aroma.
Hops are used in the brewing industry for two main purposes: to provide bitterness and aroma. Hop cones contain specific yellowish powder between their leaves – the so-called lupulin glands, which accumulate bitter substances, also known as alpha acids, and essential oils, used to provide a specific aroma. Alpha acids begin to dissolve in water only during the cooking process, and the longer hops boil in beer, the more bitterness they convey to the drink. Therefore, in order to make bitter beer, hops have to be added at the beginning, and boil for a long time.
Hops for beer aroma are added at the end of boiling or poured to a hot wort at the end of boiling. It is because the aromatic oils in dried hop cones are lost during cooking. Aromatic hops tend to have a higher concentration of aromatic oils and a smaller amount of alphas, but recently hybrid varieties became popular when hops have high content of the both substances. These hops are traditionally added to more expressive and bitter flavours of beer such as IPA. There is also cold hopping – when hops are added to the boiled and cooled wort, or even to the fermented beer for secondary fermentation. Then hops produce extra strong aroma and flavour.
Yeast. You cannot make beer without yeast. Yeast is used for the production of beer to convert the sugar in the wort to alcohol and carbonic acid. Also, to provide additional smell and taste characteristics to beer and convert malt and hops in the wort into flavourful homogenous beer. There is a big variety of yeast – some have neutral taste, others have fruity aftertaste, yet others are used for an unexpected taste or acidity, and some species are derived by the breweries and are consider as their property, and some yeast even describe the beer type.
Beer yeast is divided into the bottom fermentation, otherwise – lager yeast, and top fermentation – ale yeast. Top fermentation yeast includes wild yeast used in the production of lambic and similar types of beer. Ale yeast has a higher fermentation temperature, in the environment of 15-23° C they create sharper and more complex ester flavours. Lager yeast usually “work” at 7-15° C, creating more transparent beer with less expressive esters.
Yeast is added after cooling down the boiled beer to the temperature appropriate for fermentation. Immediately after entering beer, yeast comes alive and starts to multiply – going through the so-called lag-phase. Another phase is the growth cycle. Until wort has enough oxygen and nutrients, yeast growth and proliferation is active. When all the oxygen is used in the wort, the fermentation cycle begins. Yeast converts sugars in the liquid into alcohol, CO2, flavour and aromatic substances. On average, this process takes 3-7 days until yeast absorbs sugars and the total alcohol content does not exceed the alcohol tolerance of yeast. The last cycle is sedimentation, which begins at the end of fermentation. Yeast clump together, forming the particles visible to the naked eye, then deposit at the bottom of the fermentation vessel, and settles down. Depending on the type of yeast, the sedimentation process can take from several days to several weeks.