Stages of brewing. Features of the technological process of brewing
Many beer lovers often do not know how this drink is made. The magazine The Beer Connoisseur has produced a magazine that briefly describes main stages of beer production..
Brewing malt. Photo: Financial Tribune
Malt
Brewing begins with barley, wheat, oats or rye sprouted in the malt shop. The grain is then dried in a dryer and sometimes roasted, a process usually carried out in a separate room from the brewery. In the brewery building, malt is passed through a crusher to open the shell of the grains. This helps extract more starch during the mashing process. Large breweries also use soaking before crushing.
The combination of different grains in the brewing process is often referred to as grain balance.
Mashing
The first step in the brewing process is mashing, in which crushed malt (grain) is placed in mash kettle. Mashing is the process of mixing grains with water and heating the resulting mixture to a temperature of 40 to 80 ºC. When mashed, the natural enzymes found in malt break down starches, turning them into sugars, which then become alcohol. This process takes an average of one to two hours. The temperature of the mash can be gradually increased, or the mash can be left at a certain temperature at the discretion of the brewer. At different temperatures, different enzymes are activated, which affects the extraction of proteins and fermentable sugars. Proteins play a less important role, but are important for the formation of foam in the finished beer. Steam is used for heating in most breweries.
Infusion and decoction method of mashing
Water is mixed with grains in one of two ways: infusion or decoction. When mashing infusion the way the grain is heated in one container (mash tun); when mashing decoction In this way, part of the mash is removed from the mash kettle and boiled in a separate container, and then returned back to the original mixture. Some brewers repeat this process two times (double mash) and even three times (triple mash).
The resulting liquid in the mashing process, consisting of sugars and water, is called must.
(Note: Brewing beer from malt extract uses concentrated malt syrup or powder consisting of crushed grain, which is mixed with hot water to make the wort. This method is most often used for home brewing beer, which allows you to skip the steps necessary to separate brewer's grains from the wort).
Pumping
Straining or filtering the wort is the process of separating the wort from the grains as efficiently as possible. It is typically done in a separate decanting vat, although the mash filtration process is currently available to both large and small breweries.
The bottom of the decanting tub has round or longitudinal holes, as well as holes for draining. The solids from the mash remain at the bottom and form a wort filter.
The pumping process consists of three stages: mash-out, recirculation and rinsing. Mash out heating the wort to 76 ºC, which stops the enzymatic reactions and retains the fermentable sugars in the wort, and also makes the wort less viscous, facilitating further work.
Then carried out recycling wort and a filter layer is formed, with the help of which particles of grain are naturally separated from the wort, which makes the wort more transparent.
As soon as the wort is cleared, the remaining spent grains, consisting of the husks and particles formed during the mashing process, must be washed. Washing grains is carried out with warm water in order to get as many sugars as possible from the grains for the wort.
After washing, the grains are usually used in feed for livestock and pigs or used in the production of bread.
Boiling
Having received the wort, it is sterilized by boiling in a cauldron. In this case, the activity of enzymes is suspended, and the liquid evaporates. During the boil, which typically lasts 60 to 120 minutes, hops are added.
Photo: +Russ Hopping
The flavor, aroma, and bitterness that hops impart to a beer depends on the stage at which it is added. Hops can be added at the very beginning of the boil to give more bitterness: the more time it is boiled, the more bitter the drink will be. In the middle of the boil, hops are added for a brighter taste, and at the end - for taste and aroma.
Hops can also be added after the boil by swirling (flavor/aroma), fermentation (dry hopping for aroma), or maturation (dry hopping for aroma).
Vortex mixing
At the end of the boil, vortex mixing is carried out, which makes the wort even more transparent by removing proteins and hop particles that settle at the bottom. These particles are called sediment. A brew kettle can be used for vortex mixing, but many breweries have a special container for this.
Hop separator is a vortex mixing tank that has a separate chamber with hops to filter the sediment. This allows you to give the wort a brighter hop aroma. The hop separator is often used when whole hop cones are added to the boil. A standard whirlpool is best used to separate the lees that form when pelleted hops are used.
Fermentation
The wort is pumped into the fermentation tank, and yeast is added (added) to it. This stage is called main fermentation- sugars are converted into alcohol and carbon dioxide. The result is an ale, or lager, from the yeast used. (In the production of hybrid beers, one of these two types of yeast is also used).
After adding yeast at the correct temperature, the beer is usually kept at 15 to 20 ºC (ale) or 10 ºC (lager). During the conversion of sugar into alcohol by yeast, heat is generated, and this process must be strictly controlled. A higher temperature when using yeast for ale leads to a more active formation of aromatic organic compounds - esters.
Maturation
During the aging process, ales and lagers mature and acquire their final flavor, and the amount of fermentation by-products is reduced. Dry hopping can also be carried out at this stage to achieve a more pronounced aroma. More complexity can be added to the taste through other methods, including barrel aging.
Cold storage of beer for 30 days, known as lagering, defines the main differences between lager compared to ale: greater transparency and a different taste.
For the production of lagers, the method is also used secondary fermentation, which is called the German word "Kreusening". After the fermented "young" beer is pumped into cold storage tanks, actively fermented beer with added yeast is added to it. This extra dose of yeast activates the production of carbon dioxide and helps to eliminate the undesirable effects of the main fermentation - diacetyl (or butter taste) and other compounds.
The aging process can last from one to six weeks, and sometimes longer. Depending on the style, the brewer may filter out the remaining yeast or other particles in the beer and then place it in the maturation tank. To make the beer more transparent and increase the shelf life, pasteurization can be carried out.
Fort Point Brewery. Photo: Matthew Ankeny Bottling and carbonation
Once the fermentation process is complete, the beer must be kegged or bottled and carbonated, either naturally or by force. With forced carbonation, CO 2 is injected into a high-pressure tank to carbonate the drink. Forced carbonation is used more often, as it allows you to speed up the process and makes the beer even more transparent.
During the fermentation stage, kreuzening can also be used for carbonation. In addition, aging in bottles or the addition of a small amount of sugar and yeast when bottling is also used for this.
Experiments
Experimentation is the soul of brewing, and every aspect of the process can be changed - ingredients, mashing and fermentation temperatures, as well as their duration.
Indicators
Key metrics, measured with liquid gravity meters, help brewers control the fermentation process.
- Density- the ratio of water to other substances contained in water, including sugar
- Initial density(OG) - gravity of the wort before adding yeast
- Final density(FG) - density after completion of the fermentation process
- ABV- initial gravity and final gravity - the main variables for calculating the volumetric alcohol content (ABV)
The classical technology of beer production includes the following main stages: obtaining malt from barley, wort preparation, wort fermentation, aging (fermentation) of beer, processing and bottling of beer. This is a long and complex process that lasts 60-100 days and largely depends on the qualifications of the brewer. Despite the fact that the raw materials are the same components, the quality of beer produced by different enterprises is different.
Getting malt. IN In brewing, malt plays the role of a source not only of active enzymes, but also of that complex of organic (primarily water-soluble sugars) and mineral substances, which makes it possible, with the participation of these enzymes, to obtain beer wort suitable for fermentation. The more simple sugars necessary for fermentation accumulate in the malt, the more active the fermentation process will go and the more alcohol will accumulate.
Barley used to make malt is soaked in special vats of water at a temperature of 12-17°C. In the grain, as moisture increases, cellular enzymes are activated and the biochemical processes catalyzed by them are accelerated. This leads to a sharp increase in the intensity of respiratory processes and an acceleration of the hydrolysis of polysaccharides to simple sugars necessary for these biochemical processes. Soaking is suspended when grain moisture reaches 42-45% in the production of light malt and 45-47% in dark.
Losses of sugars on respiration processes during the soaking period reach 1.5%, while amylolytic and proteolytic processes acquire the greatest activity.
For germination, the soaked grain is sent to malting houses of various designs (boxes or drums). The malting process is carried out at a temperature of 15-19°C and good grain aeration for 5-8 days. At the same time, the endosperm of the grain softens by the end of malting and is easily triturated due to the hydrolysis of starch by amylases, and hemicelluloses by cytase (a complex of enzymes). Soluble sugars accumulate in the germinated grain - maltose, glucose, fructose and other sugars, which give the malt a sweetish taste. During the hydrolysis of phytin by the enzyme phytase, inositol and calcium-magnesium salt of phosphoric acid are formed. The presence of inositol in the wort stimulates the vital activity of the yeast, and phosphoric acid determines the acidity of the malt and wort.
Due to the activation of proteolytic processes (proteinases, peptidases and amidases), complex complexes of nitrogenous compounds are hydrolyzed with the formation of soluble proteins, peptones, amino acids, and ammonia.
In the process of grain germination, along with hydrolysis, the processes of synthesis of physiologically active compounds also occur. Thus, malted barley accumulates B vitamins, tocopherols, and ascorbic acid. The content of riboflavin especially increases (up to 210 mg per 100 g of dry matter). Subsequently, during the chemical interaction of hydrolysis products with active compounds, new aromatic and flavoring substances characteristic of sprouted and dried grain are formed. Therefore, beer cannot be obtained from raw (green) malt.
To give the necessary properties and good keeping quality, the malt is dried at various temperature conditions to a residual moisture content of 2-3.5%. Various temperature regimes and drying duration allow to obtain malt with different quality indicators and corresponding technological properties. The type of beer produced (light, semi-dark, dark) will, in turn, depend on the quality of the initial malt.
For the development of domestic varieties of beer, the following types of malt are obtained: light, dark, caramel and burnt.
Pale malt obtained by drying germinated barley for 16 hours with a gradual increase in temperature from 25-30 to 75-80°C. Depending on the quality, light malt is divided into three classes: high quality, first and second. In finished form, it has a light color, sweetish taste, malty aroma, loose mealy endosperm and high saccharifying ability. Use it for most beers.
For getting dark malt germinated grain is dried for 24-48 hours at a higher temperature, reaching 105°C at the end of the process. Dark malt is not divided into classes. In addition to the brown-yellow color, dark malt differs from light malt in the brittleness of the endosperm and a lower saccharifying capacity. Use it for dark beers.
Caramel malt, depending on the quality, is divided into two classes: first and second. In color, it can be from light yellow to brownish with a glossy sheen. For its production, dry or green malt with a high content of sugars is used, which is roasted at a temperature of 120-170 ° C. Since caramelization of sugars occurs at such a high temperature, as well as Maillard processes, the appearance of the grain on the cut is a sintered brown mass. Charring of grain is not allowed for this type of malt.
Roasted malt- These are dark brown grains, without black color. It is prepared from green malt by preliminary moistening and subsequent roasting at a temperature of 210-260°C. As a result, a taste and smell reminiscent of coffee are formed, without a burnt and bitter taste. The type of grain on the cut is a dark brown, but not black mass.
In the process of drying and roasting malt, intensive chemical processes occur with the formation of specific aromatic and coloring substances. The pentoses accumulated as a result of hydrolysis are converted into furfural and other aldehydes and aromatic substances that cause the smell of malt (rye crust). The colored components of malt are products of the destruction of sugars as a result of caramelization and melanoidin formation, which proceed most intensively at temperatures above 80°C. Melanoidins, which have surfactant properties, are good foaming agents, and therefore dark beers produce more foam.
After drying, the malt is freed from sprouts, since they give it hygroscopicity and a bitter taste due to the presence of the hordenine alkaloid. The need for this operation is also connected with the fact that amino acids accumulate in the sprouts, which, getting into the wort, are the source of the formation of fusel oils during fermentation. Malt acquires its final readiness for use only after 3-5 weeks of aging (ripening) in warehouses.
The finished malt is polished, freed from the remnants of sprouts and impurities, passed through magnetic apparatus, and then fed to malt crushers. The rate of starch saccharification, the level of wort extract, and the duration of filtration depend on the degree of crushing of malt.
Wort preparation. Crushed malt, and optionally unmalted materials, are mixed with hot water in a ratio of 1:4. The resulting mixture is slowly stirred while heating to a temperature of 50–52°C for 10–30 min. 15-20% of malt solutes pass directly into solution without enzymatic treatment. At the same time, enzymatic hydrolysis of water-insoluble nitrogenous substances and phytin occurs. Then the mixture is transferred to the mash vats, where, under the action of malt enzymes, further hydrolysis and the transformation of water-insoluble substances of the raw material into water-soluble ones, forming the extract of the future wort, take place. To ensure the maximum transition of substances into solution, the mash is slowly heated with constant stirring to 70-72 ° C (infusion method).
In another (decoction) method, 1/3 of the mash is pumped into a boiler, where it is boiled for 15-30 minutes, after which it is combined and mixed with the rest of the mash. Repeating this operation 2-3 times, bring the temperature of the entire mash to the required value. At the same time, the duration of the entire mash preparation process is 3-3.5 hours. This mashing of malt is necessary for further enzymatic hydrolysis of starch. The sequence of starch transformations during hydrolysis under the action of a- and |3-amylases is as follows:
♦ starch-amylodextrins-erythrodextrins-acro-dextrins;
♦ maltodextrins—maltose—glucose.
Along with the complete saccharification of starch to glucose in the mash, protein proteolysis is completed, the products of which play an important role in the formation of the organoleptic properties and stability of beer during storage.
The sugared mash is then sent to filtration to separate the liquid portion of the wort from the solid phase of the mash. In this case, the filter layer is formed by the solid phase of the mash itself - beer grains (non-hydrolysable components, cell membranes, proteins coagulated when heated), settling on the grids of filter vats, filter presses used to filter beer wort. It is also possible to separate brewer's grains with the help of self-unloading centrifuges.
The filtered wort and the grains of water obtained after washing are transferred to a wort kettle for boiling with hops, evaporation to the desired concentration and sterilization. At high temperatures, enzymes are completely inactivated and coagulates part of the soluble proteins, while the bitter and aromatic substances of hops dissolve in the wort. At the same time, large flakes of coagulated protein, settling, capture particles of turbidity and thereby clarify the wort.
Hop a-acid (humulone), which, when boiled, turns into isohumulone (highly soluble in water), is mainly the source of the peculiar bitterness characteristic of beer. Solubility (3-acids is negligible, and soft sch-resin is hydrolyzed to form (3-resin) and isobutylaldehyde and acetic acid are eliminated, which are involved in the formation of the specific aroma and taste of both wort and beer. Hop consumption rate, depending on the type of beer and its formulations, ranges from 22 to 45 g/da l.
The hopped wort, brought to the desired density, is passed through the hop maker, cooled to 4-6 ° C, and then freed from coagulated proteins using separators. During these operations, the must is finally clarified and saturated with oxygen, which is necessary for the development of yeast.
Wort fermentation takes place in open or closed, wooden or metal containers with special bottom and top fermenting yeast races. For special varieties of porter, at the end of fermentation, weakly fermenting yeast of the genus Brettanomycetes is introduced, which gives the beer a special specific aroma. On the surface of the wort, 15-20 hours after the addition of yeast, a strip of white foam appears (zabela stage), and then the entire surface of the fermenting wort is covered with fine-meshed foam with gradually increasing curls. Having reached a maximum, the curls fall off, the foam thickens and turns brown. The settled foam (deca) must be removed from the surface of the wort because of the bitter taste. At the end of fermentation, the bottom yeast settles to the bottom. The clarified liquid is called green or young beer. It, along with the ethyl alcohol and carbon dioxide accumulated as a result of fermentation, also accumulates a number of by-products involved in creating the taste and aroma of beer. The main fermentation process is completed in 7-9 days. At this point, about 1.5% of sugars remain unfermented in the beer.
Exposure (fermentation) of beer contributes to the final formation of consumer advantages of beer. For post-fermentation, young beer is pumped into hermetically sealed metal tanks, the inner surface of which is coated with a special food varnish. Depending on the variety, the beer is kept at a temperature of 0–3°C for 11–100 days. As a result of after-fermentation of residual sugar, the strength of beer slightly increases, it is additionally saturated with carbon dioxide and clarified. The interaction of various primary and secondary products of the main and side fermentation processes leads to the formation of new substances that determine the characteristic taste and aroma of mature beer, as well as its varietal features.
Processing and bottling of beer. After laboratory and organoleptic control, confirming the quality of the produced beer, it is processed and bottled. To give transparency, beer is filtered through pressed plates of various filter masses, and the best of them are diatomaceous earth (kieselguhr) filters. In the process of clarification, beer loses a significant part of carbon dioxide, therefore, additional introduction of carbon dioxide before bottling is allowed, followed by aging for 4-12 hours for its assimilation.
Beer is a refreshing, carbon dioxide-rich, frothy drink obtained by fermenting beer wort with special races of brewer's yeast.
Beer wort is prepared from crushed grain products: mainly barley or wheat malt, barley, wheat, corn and other grains, water, sugar and hop products.
Beer happens:
light - beer with a color of 0.4-2.5 c / unit (no more than 14 units of EBC);
semi-dark - with color 2.5-4.0 c / unit (15-40 EBC); h dark - with color 4.0-8.0 centners / unit (40-160 EBC units);
c / unit - cm 3 solutions of iodine with a concentration of 0.1 mol / dm 3 per 100 cm 3 of water.
** EBU - European Brewing Convention.
non-alcoholic - with a mass fraction of alcohol not more than 0.4%;
strong - with a mass fraction of alcohol 1.0-6.0%;
original - light beer with an extended fermentation period and an increased rate of hops;
pasteurized - with increased biological stability obtained by heat treatment;
special - prepared with the use of flavoring or aromatic additives.
The main raw materials for the production of beer are barley malt, hops and water. The taste, nutritional and other consumer properties of beer depend on their quality and preparation.
Beer production includes a number of successive interrelated technological stages, characterized by strictly regulated parameters. The correctness of all processes largely determines the quality of beer.
Malt is obtained by germinating cereals under artificial conditions at a certain temperature and humidity.
According to the method of preparation, the following types of malt are distinguished: light, dark, caramel and burnt. According to its quality indicators, it must meet the requirements of the standard - GOST 29249-92.
For the production of malt, barley is used that meets the requirements of GOST 5060-86 - "Barley for brewing". This type of raw material entering the plant must be accompanied by a quality certificate.
Nice to drink a glass of cold beer on a hot day. But does everyone know that beer brewing is a rather time-consuming technological process. We can even safely say that one of the most difficult. To get the highest quality beer, you need to provide for a lot of all kinds of nuances, calculate the amount and choose the right ingredients. It depends on such meticulous work whether the resulting drink will become a favorite for beer admirers or will remain standing on store shelves, acquiring a layer of dust.
I bring to your attention to consider some stages of the preparation of beer. Let's say the most important ones, which are used by almost all brewers.
Initially, of course, I would like to note from what raw materials this miracle drink is made. Basically, there are four main components that you can’t do without.
The first is malt. This is a product that is obtained from germinated cereals. Malt is also used in the preparation of kvass and bakery products. But in the preparation of beer, mainly only barley is used. Initially, its seeds are soaked, they are allowed to swell, because as a result of this, a very important chemical reaction begins, when starch is split into malt sugar, which is so necessary for fermentation.
The second very important element is water. The taste of beer also depends on the amount of salts it contains, so brewers take these indicators into account. A slight deviation in either direction can spoil the beer, so technologies are used that allow very accurate determination of the amount of salt in water.
The third element was also given to us by nature. This is hop. It is he who gives the beer a slightly bitter taste and aroma. Thanks to its presence, the beer foams so well. It is impossible to replace hops with anything in brewing without causing harm. Interestingly, hop cones are used only from female plants.
For excellent fermentation, of course, yeast is necessary. At the moment, Saccharomycetaceae beer yeast is used, which was specially created for the preparation of beer.
There are two distinct fermentation technologies that brewers use:
- top fermentation;
- bottom fermentation.
As you understand, this leads to the preparation of different types of beer.
And yet, what is the order of actions of brewers in the preparation of this drink and what is the industrial technology for the production of beer at factories?
The main stages of beer production
1. Preparation of the wort. Barley malt is initially crushed, but not turned into a homogeneous mass, some particles are allowed to remain rather large. The ratio of large and small particles of barley malt also leads to the emergence of new beers. After crushing, barley malt is poured with water and mixed well, "mashed". This process is called congestion. It is at this point that starch begins to break down into malt sugar. To speed up this process, the mash is heated, but do not exceed 76°C.
Now is the time to filter this wort and place it in a special sieve, in which the grated malt will stay for some time. All this is necessary so that the solid particles settle down, and clean wort can be collected, which will be used in the next stage.
2. Brewing the wort. The prepared pure wort is first heated, brought to a boil and then hops are added, the amount of which is determined depending on the type of beer. This process takes approximately 3 hours. During this period, all microorganisms die, enzymes are destroyed, after which no chemical reactions are anymore possible. At the end of the boil, the wort is filtered again and allowed to settle a little, so that even the smallest particles that could not be filtered earlier fall down. Some breweries use centrifuges to speed up the clarification and filtration process.
3. An important stage is fermentation. Pure filtered wort is poured into fermentation tanks. After it cools down, yeast is added. Here, the temperature is very closely monitored, since the taste of the product also depends on it at this moment. For top fermentation, the temperature is 18-22°C, for bottom fermentation - up to 5-10°C.
After about a day, a rather thick layer of foam forms on the surface, which indicates that the fermentation process is proceeding successfully, and the sugar is converted into carbon dioxide and alcohol. At this point, the brewers carefully monitor the temperature so that it is stable and does not rise in any way. And also monitor the level of carbon dioxide. As needed, it is diverted through special pipes. Fermentation is complete when all the sugar has been processed by the yeast.
4. Ripening. As a result of the first three stages, young beer is born, which must “ripen”. It is placed in special containers for a long four months. At this time, the temperature and pressure in these containers are closely monitored.
5. Filtration. The settled and matured beer is again filtered to finally say goodbye to the smallest unnecessary particles and become absolutely ready for bottling.
6. Bottling. It seemed, at first glance, the easiest step. Take and pour into containers. But beer is a perishable product, so the container must be absolutely clean and sterile. Failure to comply with these rules will lead to a deterioration in taste and product spoilage. Before bottling, the beer is pasteurized, which makes it possible to slightly increase its shelf life.
And only after all these processes, the desired and delicious drink hits the shelves of stores, where real beer fans are already looking forward to it. This is such a difficult technology for the production of beer at all factories.
You will most likely be interested in this
Characteristics of raw materials
Basic technological operations
Assortment and physico-chemical characteristics of beer varieties
Principal technological scheme of production
Hardware-technological scheme of beer production
Part 2 Biochemical transformations at various stages of beer production
Mashing and filtering transformations
Factors affecting:
a) the process of boiling wort with hops
b) processes during cooling and oxidation
Transformations during fermentation of beer wort and after-fermentation of beer
Part 1 Beer production technology
CHARACTERISTICS OF RAW MATERIALS FOR OBTAINING BEER
Malt and unmalted raw materials. The main raw material for the production of beer is barley brewing malt (light dark and special varieties), the characteristics of which are given in Table. 21.2. The main varietal features of beer (color, taste, smell, aroma) largely depend on the quality of malt and the ratio of its types in the recipe. The standard for beer allows the use of unmalted barley, rice chaff of wheat, defatted cornmeal. The main requirements for the quality of malt substitutes are purity and compliance with the requirements for food raw materials. The use of unmalted raw materials is economically beneficial and technologically justified. Therefore, when preparing 10...11% light beer, it is necessary to use at least 20% of unmalted raw materials without the use of enzyme preparations. When using more than 20% of unmalted barley, the use of enzyme preparations is mandatory.
In the production of beer "Zhigulevskoye" it is allowed to use raw sugar in an amount of up to 6% of the mass of the mashed grain products.
Water. The quality of water, its ionic composition have a great influence on the formation of the organoleptic characteristics of beer. Process water must meet all requirements for drinking water. It should be transparent, colorless, pleasant in taste, odorless, with a total hardness of 2...4 mg·eq/l and a pH of 6.8...7.3.
Water is considered optimal for beer production if the ratio of the concentration of calcium ions to the total alkalinity of water (alkalinity index) is at least 1, and the ratio of calcium and magnesium ions is 1:1...3:1.
Water hardness and its salt composition are regulated using various methods of water treatment: reagent, ion-exchange, electrodialysis and membrane based on the principle of reverse osmosis.
To remove an unpleasant odor, water is deodorized by passing through a column filled with activated carbon.
Hops and hop products. Hops are the traditional and most expensive raw material for brewing. It gives beer a specific bitter taste and aroma, promotes the removal of certain proteins from the wort, serves as an antiseptic, suppressing the vital activity of contaminating microflora, and increases the foam resistance of beer. There are two main types of hops: bitter and aromatic. In brewing, predominantly female aromatic hop inflorescences are used - hop cones containing lupulin. The composition of the latter includes aromatic and bitter substances.
Bitter hop substances include α- and β-acids, soft α-, β- and hard resins. The content of α-acids, depending on the hop variety, can reach 16%. The most valuable derivatives of α-acids for brewing - iso compounds provide about 90% of the bitterness of beer.
Aromatic substances are mainly represented by essential oil, the content of which ranges from 0.3 to 2%. An important component of hops is tannins, the amount of which reaches 3%.
According to the purpose, hops are divided into two groups: fine varieties with a content of bitter substances of about 15% and α-acids from 3 to 5%, used for the production of beer according to the classical technology, and coarse varieties with a content of bitter substances of more than 20%, intended for the manufacture powders, granules and extracts Dried hop cones, ground, pelleted or briquetted hops, as well as various hop extracts are used in brewing.
Hops and hop products should be stored in a dry, dark and cooled room with a temperature of 0 to 2 °C and a relative humidity of no more than 70%.
enzyme preparations. Used when using more than 20% of unmalted raw materials in an amount from 0.001 to 0.075% by weight of the processed raw materials.
Amylolytic (Amilosubtilin G10x, Amylo-rizin Px, etc.), proteolytic (Protosubtilin G10x), cytolytic (Cytorosemin P10x, Celloconingin P10x, etc.) enzyme preparations, as well as their mixtures in the form of multienzyme compositions, are used.
Amylolytic preparations are used for mashing with an increased amount of unmalted raw materials and low quality of the initial wort. They significantly increase the yield of the extract and improve the quality of the wort.
Protosubtilin G10x is used with increased amounts of unmalted raw materials and to improve the quality of wort from low-quality malts, as well as to eliminate colloidal turbidity in beer. Cytolytic preparations increase the yield of the extract due to the hydrolysis of non-starch polysaccharides, mainly hemicellulose. At the same time, the quality of the wort and the persistence of the beer are improved.
The most promising means is the use of multi-enzyme compositions (MEK), which allow maintaining the high quality of Zhiguli beer when using up to 60% unmalted raw materials.
Malting is the beginning of the process of converting barley nutrients into a form that is favorable for yeast cell growth and fermentation. The carbohydrates contained in barley grain are insoluble in water, and therefore barley needs additional processing. Malting involves steeping, germinating the barley, then drying the freshly germinated ("green") malt and removing the sprouts.
The preparation of malt is carried out in special rooms called malt houses. Most breweries do not have their own malthouses to produce malt, but use the services of suppliers. The malt is stored at the plant in special silos.
2. Crushing
First of all, the malt is sent to the malt crusher for grinding. This ensures maximum dissolution of its extract in water and a good filtration rate, degree of clarification. As a result of crushing, a mixture of husks, large and small grains, flour is obtained. According to the method of crushing, the following types are distinguished: dry crushing, dry crushing with conditioning, lock conditioning (the shell is moistened, softened, flour is obtained from the internal parts).
3. Mashing
Mashing is the process of transferring all the valuable substances of the grain into an extractive solution and preparing beer wort. In the process of mashing under the influence of temperature and at several temperature pauses, the particles of malt grinding are dissolved (they go into solution as a result of the activity of active enzymes) and starch is converted into simpler types of sugars. At the end of this stage, the wort acquires a sweet taste. The remaining insoluble constituents will later be separated in a lauter vat as brewer's grains.
The art of the brewer is precisely to find the optimum temperatures; temperature is a special beer recipe that is kept secret. In fact, beer is invented at this stage.
4. Filtering
The finished mash after mashing is pumped into a special filter vat, where the initial wort is filtered. This is necessary because in addition to the wort extract, the mash contains the shell and the inner part of the malt, the so-called grains. It is a by-product that must be separated from the wort. If the wort is not clear enough, it is run through the filter again. The clearer the wort, the better the beer will be.
5. Boiling
At this stage, the mass enters the wort kettle, where it is boiled with the addition of hops in one or more stages - “wort hopping”. As a rule, hops, which were added at an early stage of boiling, give the beer a specific taste - bitterness. The addition of hops at the end of the boil adds flavor and softens the bitterness. Boiling can last from 60 to 120 minutes. Hops give the beer a specific taste and aroma, increase its storage stability.
The amount and type of hops added depends on the type of beer being brewed. Hops are considered to be the "soul of beer". At the same production stage, the wort is brought to a certain gravity, which is expressed as a percentage on the label and is called the “extractive gravity of the initial wort”.
6. Clarification and cooling of hopped wort
The resulting hot wort is pumped into a special apparatus - a hydrocyclone, with a volume of one brew, for clarification by settling fine suspended particles of hops and protein. The principle of operation of the device is as follows: the jet of the flow of beer wort is directed tangentially, so the wort rotates inside the device. Under the action of hydrodynamic forces, suspended particles are collected in the form of a cone in the center of the bottom of the apparatus. After settling of the solids, the wort becomes clear and is removed from the sediment, first from the upper levels of the hydrocyclone, and then from the lower levels as transparency increases.
7. Fermentation
Sterile compressed air is first injected into the chilled wort stream through a special aeration and yeast dosing unit, and then brewer's yeast is dosed. Air is necessary for yeast to multiply intensively during the first 12-24 hours of beer wort fermentation. The wort is sent to one of the cylindrical-conical tanks (CCT) - the main fermentation apparatus.
Fermentation lasts from 6 to 8 days - for different varieties of our beer - at a temperature of 9-18°C. At this time, all the sugars contained in the wort are fermented, forming alcohol, carbon dioxide and a certain amount of other substances: glycerin, acetaldehyde, acetic, succinic, citric and lactic acids. Higher alcohols are formed as by-products of fermentation from amino acids, which affect the aroma and taste of beer.
All products of alcoholic fermentation formed in the wort are involved in the formation of the specific taste and aroma (bouquet) of beer.
At the end of the fermentation process, "young beer" is cooled to a temperature of 3°C. In this case, settled yeast is removed from the bottom of the CCT. This is a first generation yeast. They can be used for re-fermentation. How many times they will be used depends both on the quality of the yeast and on the cleanliness and accuracy of production, since they are able to adsorb various substances, even heavy metals. Different races of yeast determine the character of the future beer, and, as a rule, each brewery uses its own pure race.
8. Ripening
Then the beer that has passed the stage of fermentation is sent to the next stage - after-fermentation and maturation. For final maturation, “young beer” is kept at a temperature of 0‑2°C. During this period, it is saturated with carbon dioxide, there is a slow fermentation of the extract remaining in it, clarification and the formation of a bouquet and fullness of taste. After chemical analysis, confirming the readiness of the product, and tasting, the beer is sent for filtration (clarification).
9. Filtering
Since the compounds that cause haze in beer are complex and have a wide range of particle sizes, filtration using diatomaceous earth as an auxiliary material is considered to be the best method for their removal. Diatomaceous earth is a sedimentary rock that creates a porous surface through which beer passes, while particles of substances that affect haze remain.
Lastly, the beer goes through a fine purification stage, during which the smallest particles are removed. If necessary, the beer is additionally saturated with carbon dioxide through a carbonizer and sent to a storage tank - forfas, from which the beer is served for bottling.
10. Bottling
From forfas beer enters the bottling line. Our company has installed filling lines for various types of packaging: glass bottles, aluminum cans, kegs (for delivery to bars and restaurants), PET packaging. The bottling process differs depending on the type of container, but in general it includes: beer pasteurization, container preparation (washing and sterilization), bottling, labeling, packing into boxes and pallets.
Pasteurization is necessary to ensure a longer shelf life of the beer, in order to avoid changes in the taste and quality of the beer as a result of microbial activity. In this process, the beer is heated to the required temperature for a short period of time.
Beer is poured into bottles that have undergone careful processing (rejection of containers with cracks or other defects), washed inside and out, rinsed, checked for cleanliness in the laboratory. During filling into a container, regardless of its type, it is filled with carbon dioxide for a counter-pressure effect. This effect allows the beer to slowly flow into the bottle under the influence of gravity, preventing foaming, carbon dioxide leakage, oxygen ingress into the beer, and also contributes to uniform filling of the container. Then the bottles are corked, labeled, wrapped in thermal packaging, put on pallets and sent to the finished product warehouse.
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