Brew Commercial Beer

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Have you ever wondered what it takes to start and run a brewery? Commercial beer is brewed in approved, regulated breweries. Brewers must use microbiology, chemistry, engineering, and mathematics in order to produce consistent, high-quality commercial beer. Breweries are composed of precise machinery, large vessels, and various sensors and other devices that tend to be integrated. Entire breweries may be operated via computerized control systems, but manual controls are commonly used. The process that leads to packaged commercial beer is lengthy and must adhere to many standards that are used to ensure that the beer is fit for sale and consumption. Here's an overview of the process, from start to finish.

Steps

Preparation

  1. Study brewing science and learn practical brewing techniques. Learn from brewers or go to brewing school. Excellent brewing programs in the United States are offered by the University of California, Davis and the Siebel Institute of Technology. The Master Brewers Association of the Americas (MBAA) offers a 2 week Brewing & Malting course held in November each year at the University of Wisconsin in Madison (www.mbaa.com). Industry-standard textbooks written by the UC Davis instructors Michael J. Lewis [1] and Charles W. Bamforth are readily available and easy to understand. Foreign textbooks such as Technology Brewing and Malting by Wolfgang Kunze are also highly informative and can be incredibly detailed, but may be difficult to obtain as well as expensive.
  2. Create a brewing company. Choose a name, create a logo, and decide what type of beer your brewery should produce. Register your company with the appropriate local government agencies.
  3. Obtain a brewers license. Apply for and obtain a state-issued brewers license such as a small brewers license.
  4. Create beer labels. Beer that is bottled and sold commercially must display approved labels. Make sure that you can wait for a few months or so before selling bottled beer while the labels are approved by the Bureau of Alcohol, Tobacco, and Firearms or similar agency.
  5. Build or buy a brewery that has access to high quality brewing water. Find a spot where lots of high-quality brewing water can be easily obtained. Well water is generally preferred to city water, especially if city water is from different, inconsistent sources. A high hardness to alkalinity ratio may be preferred for ales, while soft water is great for pilsners. Alkaline water must be avoided. Assure that your brewery is engineered properly and can pass health department inspections, and also that it is safe for workers and customers. Also ensure that the waste water from the brewery can be sent to a local waste water treatment facility.
    • Design your brewery so that it uses electronic control systems. Valves, pumps, brewing vessels, and so forth can be controlled from centralized locations and automated with the use of computers and sensors. This saves manpower and reduces worker error.

Getting the Brewery in Order

  1. Get a forklift and learn how to drive it. Use the forklift to move around pallets of beer and many other brewery items.
    • Ensure that you have enough pallets to use in conjunction with the forklift. Use the pallets to store and move beer and other items.
  2. Stock up on malted barley. Obtain sacks of grain and/or fill grain silos so that enough grain is on hand for the scheduled brews. Also make sure that the malt meets the required specifications. The specifications should be provided by the maltster and can be tested for by the brewery. Specifications include indexes of modification, kernel plumpness, friability (friable grain is easier to mill), protein content as well as free amino nitrogen (FAN) content, enzyme activity or content, and moisture content. There is no one perfect set of specifications, as different types of brewing equipment and methods works best with different types of barley malt. For example, a traditional British 2-row malt works well with a 2-roll mill and an un-stirred infusion mash tun, while American six-row malt can mashed in a stirred mash tun with rice or corn adjuncts. Different types of malt with different degrees of modification, enzyme contents, and so forth are used with different types of equipment to make different types of beer.
    • Move grain from grain silos with an auger system. This enables grain to be moved through pipes.
  3. Procure a supply of hops. Arrange a contract with a hop supplier in order to secure a steady supply of hops at a certain reasonable price, if possible. Hops can be expensive and in short supply. Make sure that the hops are stored in sealed, airtight containers under refrigeration and that they have the right alpha acid content so that the proper amount of bittering will be contributed to the beer from the hops during boiling. Alpha acids become iso-alpha acids when they are boiled in the sweet wort that is produced during mashing and lautering. Hops may take the form of whole cone hops or pelletized hops. Pelletized hops are more resistant to spoilage or deterioration, and are merely whole cone hops that have been pulverized into a powder and shaped into pellets. Liquid hop extracts that are concentrated sources of alpha acids and, in some instances, already isomerized iso-alpha acids, are also available. Pre-isomerized extracts may be added directly to finished beer, although it is always still necessary to boil the sweet wort when making beer.
  4. Choose one or more yeast strains and obtain enough yeast to pitch into your first batch of beer. Find a yeast strain from a yeast lab or use your proprietary yeast that will produce the type of beer that you want to brew, and have the proper quantity to pitch into the fermenter. Use absolutely hygienic, aseptic conditions and equipment when handling yeast so that the yeast does not become contaminated with wild yeast, unwanted strains of brewers yeast, or with bacteria. Wyeast Laboratories and White Labs will grow pure yeast strains for breweries as well as store and grow proprietary yeast strains in aseptic facilities. An industry standard for the amount of yeast to be pitched into beer is one million cells per milliliter wort per degree Plato of wort, although exact pitching rates are variable for different types of beer. Degrees Plato can be converted to or derived from specific gravity. Also use a quantity that will enable the yeast to multiply about five times before the fermentable wort sugars are consumed by the yeast. Buy liquid or dry yeast, depending on the sophistication of your brewing facilities. Store or propagate the yeast in a yeast propagator if necessary or desired. Also store yeast in the cooled cones of cylindroconical fermenters or in other vessels that are sanitary, cool, and sealed from incoming air. Be sure to let the CO2 that yeast generates vent out of the vessel so that too much pressure does not accumulate and create an explosive event.
  5. Fire up the steam boiler. Start the steam boiler and keep it running so that steam is always available. Breweries require steam for various heating duties. Also have a hot conventional water heater for hot water, which is always required. Also use heated water that is returned from the heat exchanger.
    • Pipe the steam to the vessel heating jackets and other destinations.
    • Run the steam condensate back to a condensate reservoir that feeds the boiler. Condensate is a liquid that forms as steam condenses and forms liquid. When steam condenses, it gives up much energy, and therefore transfers heat to the material to be heated.
  6. Start up the glycol chiller. Maintain cold glycol or other refrigerant to cool hot wort, maintain fermentation temperatures, and chill beer so that a consistent, quality product is produced. Pipe chilled glycol to cooling jackets and other destinations. Use a glycol tank as a glycol reservoir.
  7. Fill the CO2 tank. A supply of carbon dioxide is required for pressurizing tanks, carbonation, and other brewery tasks. Use gas tubing to connect CO2 nozzles.
    • Pipe the CO2 to output nozzles inside the brewery.
    • Connect the CO2 to nozzles (often inputs) that are connected to tanks and other equipment.
  8. Clean and sanitize brewery equipment. Clean hot-side brewery equipment prior to brewing. Clean and sanitize all hoses, pipes, fittings, pumps, heat exchangers, tanks, filters, and other equipment that will contact the cold-side wort and beer. Use caustic soda as a cleaner and chemicals such as peroxyacetic acid for sanitization. Ensure that all caustic and other cleaning chemicals are rinsed from the equipment before adding the sanitizer. Ensure that correct temperatures are used for all chemicals. Sanitize equipment soon before use to limit the chance that contaminating organisms will grow.
    • Use CIP (cleaning-in-place) for most brewery vessels. Use spray balls, gamma jets, or other CIP technology for cleaning duties whenever possible. CIP devices disperse water, cleaning agents, and sanitizer in closed vessels causing the entire inside surface of the vessel to be cleaned and sanitized. Also use CIP devices to heat and cool vessels with hot and cold water, respectively.
    • Use a centralized reservoir of cleaning and sanitizer solutions. Pump the solutions to the desired locations.
    • Use a keg washer to effectively clean and sanitize kegs. Keg washers also purge and fill kegs with carbon dioxide so that the beer that they are filled with does not become oxidized.
  9. Connect equipment with hoses, pipes, valves and clamps. Connect vessels such as the heat exchanger and fermenters with hoses and pipes, and ensure a sanitary connection that is not exposed to the atmosphere. Run cleaning solution and sanitizer through the pipes and hoses while they are connected to the vessels before using them.
    • Use gaskets between hoses and valves or other fittings to form a sanitary, leak-proof seal.
    • Keep a supply of hoses and hang them up to keep them clean and dry.
    • Use sanitary butterfly valves and ball valves for many brewery applications. Direct product and service fluids and gases to desired locations with such valves.

Making the Beer

  1. Determine the quantity of yeast to be harvested from a fermented batch of beer for the new fermentation. Count yeast cells with a hemocytometer and a microscope or use a different desired method to determine how much yeast needs to be added to the fermenter in order to achieve the desired finished beer. Use about one million cells per milliliter wort per degree Plato of wort. Discount dead yeast cells by staining them with methylene blue while counting them with the hemocytometer.
  2. Pitch the yeast into the fermenter. Add the yeast to the fermenter to which the freshly brewed, chilled and oxygenated wort will be added. Pitch a specific, desired quantity using a device such a peristaltic pump. Pitch from a yeast propagator, yeast brink, or from the cone of a cylindroconical fermenter. Re-pitch yeast from previous fermentations a limited amount of times, perhaps twelve to twenty times. Repitch less for high-gravity beer, perhaps five to eight times. Discard old yeast. Test yeast for bacterial infection or unwanted mutations, and discard it if necessary. Infected yeast can be acid washed to kill the bacteria but not the yeast. Therefore, yeast must be discarded when contaminated with wild or unwanted yeast strains.
    • If desired, let batches of beer in open fermentation vessels ferment spontaneously. This involves letting wild airborne yeast inoculate the wort instead of adding pure-culture brewing yeast. This method will also allow airborne bacteria to inoculate the wort, although certain bacteria may be desirable for spontaneously fermented beer.
  3. Mill the barley malt. Mill the correct weight of barley malt. Use the grain mill to break the barley malt into smaller particles. Set the mill gap to the correct setting, depending on the specific type or variety of barley malt, so that a correct crush is achieved. Ensure that the husk is essentially just broken in half and that the correct percentages of coarse grits, fine grits, and flour are achieved for the brew system and malt that are used. The grits and flour come from the inner starchy endosperm of the grain. This is converted into fermentable sugars during the mash by the natural barley enzymes.
    • Two roll, four roll, and six-roll mills can be used, depending on the type of malt and brew house used. Use two-roll mills with highly modified malt, such as traditional British two-row malt, and use six-roll mills with less modified malt such as American six-row malt.
    • Modification of barley malt occurs when living barley kernels are malted in a malt house. Malting involves germinating the grain and then kilning it. Modification is a natural process and occurs during germination. Natural barley enzymes work on the barley grain to break down cellular structures. Modification also involves the activation and synthesis of barley enzymes that are needed for the conversion of barley malt starch to fermentable sugars during mashing. When the cellular structures of the barley kernels are broken down, the grain also becomes more "friable" (easier to mill). Six-roll mills break up the malt more thoroughly, thus physically breaking up cellular structures that were not broken up enzymatically during malting.
    • Hammer mills that pulverize grain are used with mash filters instead of conventional lauter tuns. Wet mills keep the grain husk more intact than with conventional mills, and such mills may improve yield.
    • Grain can be automatically added to to mill from the grain silo and transferred to the grist hopper.
  4. Store the milled grist in the grist hopper. Milled grain is referred to as grist. Account for the angle of repose that the grain will form in the hopper. Hoppers may be used to weigh the incoming grain, and milling can be shut off automatically when the correct weight of grist is obtained.
    • Use an auger system to move grist from the mill to the grist hopper if the hopper is located above the mash tun. If the grist case is located below the mill but the grist case is not above the mash tun, use an auger system to move the grist to the mash tun from the grist case when ready to mash in (add grist and water to the mash tun).
    • Make sure that the premasher plates that keep the grain from falling into the mash tun are in the closed position, especially if the grist hopper is situated directly above the mash tun. The premasher is attached to the top of the mash tun and is directly below the grist case or connected to the auger system that moves grist into the mash tun.
  5. Heat brewing water in the hot liquor tank. Ensure that the hot liquor tank is filled, and heat the water to about {{safesubst:#invoke:convert|convert}} or higher without boiling it using the hot liquor tank steam jackets or other method. When brewing multiple batches of beer, be sure to use water that was heated when it passed through the heat exchanger to replenish the hot liquor tank. The hot wort is cooled with cold water to fermentation temperature, thus producing heated water and cooled wort.
    • Make sure that the cold liquor tank is full and in working order. As with most other tanks, use the attached level indicators to determine the volume of fluid in them. Level indicators may be narrow clear tubes that hang from the top to the bottom of the tank, and the level of fluid in them correlates with the level of fluid in the tank.
  6. Begin adding water to the mash tun. Add some hot water to heat the mash tun and form a cushioning layer on the bottom of the mash tun.
    • Mash tuns can be stirred or unstirred, and can double as lauter tuns. Stirred mash tuns that are used with separate lauter tuns are typically smooth vessels that have a water inlet in their ceilings, and an outlet at their lowest point that allows the mash to be pumped to the lauter tun.
  7. Mash in. Pull the mash tun premasher plates that will allow milled grist to fall into the mash tun and add hot water as well, allowing the grist to mix with the water in the premasher chamber that is attached to the top of the mash tun.
    • Let the mash tun fill with the water and grist mixture. If the mash tun is stirred, mix the grain and water mixture as it falls into the mash tun.
  8. Adjust the incoming mash water temperature. Make sure that the desired mash temperature is achieved. Mix hot liquor and cold liquor (water) to achieve the proper temperature. The grain, mash tun vessel, and environment will absorb heat from the water, and therefore use water that is hotter than the desired mash temperature. Calculate the water temperature needed based on these factors. Allow all the desired grain and water into the mash tun in order to achieve the desired water to grist ratio. Use a flow meter to measure the water volume. Different volumes of water relative to grist weight are used depending on the brewing system and style of beer. A large factor involves the type grain to be used. For example, traditional British ales mashed in infusion mash tuns will use less water per unit grain. This is because infusion mash tuns are unstirred, but also because the barley enzymes that create sweet wort are preserved better in a thick mash. While traditional British malt is well modified, it is also low in enzymes. Six-row malt used to make beers such as Budweiser are very high in enzymes, and therefore a thinner, hotter mash can be used.
  9. Let the mash rest at the conversion temperature and, if desired, at initial lower temperatures.
    • Use initial lower temperatures. These stages are referred to "doughing in" as well as the protein rest. The protein rest occurs at about 122 degrees, and may actually be best referred to as the beta-glucan rest, as it may help to break down beta glucans which can cause lautering difficulties. The protein rest may also induce malt enzymes to break down proteins or peptides, thus creating amino acids and/or small peptides.
    • Provide the natural barley enzymes with the proper amount of time and the proper temperature(s) needed to convert the barley starch to fermentable sugars. This phase is the conversion rest. The conversion rest may last about 90 minutes, depending on the type of beer being made and the type of equipment being used. The conversion temperature can be reached immediately after mashing in, or achieved by further heating the mash tun after mashing in.
    • Heat the mash tun. A "programmed mash" will use heating jackets or direct fire to incrementally heat the mash. However, the mash can also be heated by adding boiled adjuncts such as rice or corn. This is referred to as double mashing, and requires a separate cereal cooker. Adjuncts of course also add starch that must be converted to fermentable sugars by the malt enzymes during the conversion rest. Add ten percent barley malt to the adjunct in the cereal cooker and rest briefly at 158 degrees so that the alpha amylase enzymes from the malt can liquify the adjunct starch and make it pumpable. Otherwise, it will form a solid, unpumpable mass. As the boiled adjunct is pumped over to the main mash, it creates an increase in temperature that is referred to as a "temperature ramp". Another method involves removing a portion of the mash and placing it in a smaller, heated vessel. This is brought to a boil, then add back to the primary mash to increase the overall mash temperature. This is referred to as decoction mashing, and can involve one to three steps where portions of the mash are removed, heated, then returned to the main mash.
    • Attain the correct conversion temperature(s). Conversion temperatures are variable depending on the desired beer style, but temperatures between 130 degrees and 155 degrees results in adequate activation of the desired barley enzymes. A single rest at 149 degrees may be desired for certain styles of beer, especially traditional British ales. Provide a rest at 131 degrees to activate beta amylase and a rest at 149 degrees to activate alpha amylase in addition to beta amylase. Heat to 160 degrees or higher to inactivate and denature these enzymes. Beta amylase will begin to be deactivated when the mash is heated to temperatures that favor alpha amylase. To achieve a high degree of wort fermentability, ensure that beta amylase is adequately activated. To ensure that overall extract is achieved, and that the malt and adjunct starch is adequately converted to sugars and dextrins, ensure that beta and alpha amylase are adequately activated. They work together to break down starch.
  10. Pump the mash to the lauter tun. Prepare for pumping by first adding an initial shallow layer of hot foundation water to the bottom of the lauter tun that just covers the false bottom. Then pump over the mash. Use a properly sized centrifugal pump for most pumping duties. Most transfers in the brewery are conducted with pumps.
  11. Begin running off the sweet wort. After pumping over the mash, recirculate (vorlauf) the wort. This allows the wort to run through the grain bed, out the bottom of the lauter tun, then up to the top of the lauter tun and back through the grain bed again. Do this until the wort is relatively clear and free of particles. Then stop recirculating the wort and run it into the boil kettle from the lauter tun. Use the lauter tun to separate the converted sugars from the grain husks and other unusable grain material. Continually run the sweet wort into the boil kettle.
    • The grain bed rests on the false bottom (narrow grates) in the lauter tun. It forms a level, relatively compact filter bed that is established during the vorlauf phase. The wort flows from the grain bed and down through the grates, leaving the grain husks and other unwanted grain material behind. Ensure that the grain bed is very level and relatively undisturbed so that runoff is even and uniform.
  12. Begin heating the boil kettle. As wort enters the boil kettle, begin heating it with integrated steam jackets and/or internal or external calandria. Account for the amount of time that will be required to bring the wort to a full boil. Calandria operate by running wort through tubes that are surrounded by steam. The wort is heated to a boil as it passes through the tubes, and is circulated continuously.
  13. Sparge the grain in the lauter tun. Spray the wort with hot water from above to rinse residual sugars from the grain. Continue running off the sweet wort that is now more dilute due to the addition of hot sparge water.
  14. Check the wort clarity while it is running off from the lauter tun to the boil kettle with a sight glass. Ensure that the clarity is good, and that there is not too much particulate matter.
  15. Run the lauter tun rakes. Cut through the grain bed to increase runoff. Use the rakes to reduce the change in pressure that occurs through the grain bed from top to bottom. Not all lauter tuns have rakes, and some mash tuns double as lauter tuns. Such mash tuns may be unstirred and may not be equipped with rakes.
  16. Grain out. Remove the spent grain from the lauter tun after it has been drained of sweet wort and undesired liquid. Use a hoe or an auger to remove the grain.
  17. Dump the spent grain into a trailer. Arrange for a cattle farmer to pick up spent grain soon after brewing so that it can be a valuable food source for cattle and some other animals.
  18. Boil the wort. Obtain the correct volume of sweet wort in the boil kettle, and bring it to a full, rolling boil. Use an internal or external calandria, steam jackets, or direct fire to heat the kettle.
    • The boil must be vigorous and active to mix the hops around and induce proper hop isomerization. Hop alpha acids must be isomerized during the boil in order to imbue bitterness to beer. Boil for 45 minutes to two hours, depending on the style of beer and equipment that is being used. Boil off the required volume and volatilize (boil off) unwanted compounds such as dimethyl sulfide, which is derived from the barley malt.
    • Keep the boil kettle closed or just cracked open so that heat is not lost and the boil is efficient.
  19. Measure the wort specific gravity. Check the specific gravity with a hydrometer or other device before and after boiling to obtain the correct gravity or sugar content for fermentation.
  20. Add the hops to the boil kettle. After the wort has been brought to a boil, add the first hop addition to add bitterness and other hop characters to the wort. Then add additional hops later in the boil if desired. Flavor and aroma hops are added during or after the end of the boil, as the hop oils that contribute to flavor and aroma are lost if hops are added earlier. For lots of hop aroma, add hops during fermentation. This is referred to as dry hopping.
  21. Transfer the boiled wort to the whirlpool. Use the whirlpool to cause the wort to flow in a circular path, thus creating a force that causes unwanted trub particles to the center of the bottom of the whirlpool, separating them from the wort. Trub is coagulated protein, hop pellet particles, and other material that should not be in finished beer. Add hops to the wort in the whirlpool if desired. Whirlpools are commonly used, but some brewing systems may not use them. Brewing systems that use whole hops in conjunction with a hop back to remove trub should not require a whirlpool.
  22. Remove trub from the whirlpool. Add the trub to the spent grain if desired. The trub is removed through the bottom of the whirlpool, and can be added to the spent grain trailer.
  23. Cool the wort with the heat exchanger. Ensure that the wort is cooled to fermentation temperature. Ales may be fermented at about 68 degrees, while lagers may be fermented at about 55 degrees. Drain the whirlpool and simultaneously send the hot, whirl-pooled wort through the heat exchanger and to the fermentation tank. Maintain a higher pressure on the wort than on the coolant to prevent coolant leaks into the beer. Water used for primary cooling can cause microbial contamination. Food-grade glycol, generally used for secondary heat exchanger cooling (if needed) is not meant to be a food additive. Typical heat exchangers, such as the one pictured, are plate heat exchangers that cause product and coolant to flow near each other on opposite sides of the plates, and heat is passed from hot liquid to cooler or cold liquid.
  24. Aerate the wort. Send the cooled wort past an aeration/oxygenation stone using compressed oxygen from a gas cylinder. Oxygenation and carbonation stones are generally finely perforated stainless steel rods that allow fine bubbles of gas to enter the liquid wort or beer. Make sure that the wort is oxygenated to about twelve parts per million so that the yeast can multiply. Yeast consumes oxygen, but ensure that this is the only time in the brewing process that oxygen is added in order to avoid unwanted oxidation of the beer.
  25. Fill the fermenter with the cooled, oxygenated wort. Ensure that the fermenter is not overfilled, and when using cylindroconical fermenters about twenty percent of the overall capacity should remain unused. Add multiple, consecutive brews if the fermenter has enough capacity. Cylindroconical fermenters are closed to the open air and enable rapid, consistent fermentations. This is because the CO2 that is produced by the yeast during fermentation is evolved in part towards the bottom of the fermenter, and as a higher hydrostatic pressure exists at lower levels, the CO2 moves upwards through the center of the fermenter. As the CO2 moves upwards, a flow is produced that mixes the fermenting wort up through the middle then down past the sides and so forth. This causes mixing but also forces flocculated clumps of dormant yeast that is done fermenting and unwanted trub particles down to the cone of the fermenter, where they can be removed. One or more cooling jackets are built into the walls of the fermenters, and the fermenter cones are equipped with valves that allow beer and yeast to be added to the fermenter as well as removed. Ports that exist in the top of the fermenter are for the CIP device and addition of CO2 for top pressure as well as for the removal of CO2 that is produced by the yeast during fermentation. CO2 may be recovered from the tanks, purified, and used for brewery applications such as carbonation.
    • Open fermenters can be used to brew certain traditional ales, but open fermentation generally needs to be conducted in special sanitary rooms that are equipped or connected to special cooling devices. Entire lower floors may be occupied by cooling apparatus. CO2 must also be vented and monitored, as the CO2 produced by the yeast is free to move directly into open air. With traditional open ale fermentation, yeast is harvested (skimmed) from the top of the fermenting wort. This method allows results in the harvesting of relatively pure yeast, as much unwanted material including contaminating bacteria sink to the bottom of the fermenting wort and are not harvested with the yeast.
  26. Allow the wort to ferment. Allow the fermentation gasses and yeast blow off from the top of the fermenter to pass into a bucket of water, thus sealing the tank from the atmosphere. Maintain the desired fermentation temperature with the cooling jackets that are built into the walls of the fermenter. Ensure that the heat that is generated by the yeast during fermentation is adequately counteracted by the cooling jackets. Measure the specific gravity to check the progress of the fermentation, and ensure that the sugars are being fermented by the yeast.
    • After the active, initial blowoff is complete, replace the bucket of water with a fresh one. The carbon dioxide that is generated from active fermentation will be visible as bubbles that pass from the hose and into the water, and this will subside as the sugars in the wort are consumed by the yeast.
    • End primary fermentation when a certain target specific gravity is reached. The specific gravity that determines the end of primary fermentation will vary depending on the method of secondary fermentation that is used, as well as the type of beer style that is desired.
  27. Begin secondary fermentation. Cool the cone of the fermenter to about 41 degrees and the fermented wort to about 50 degrees (depending on beer style and brewing technique). Drop or transfer yeast and trub from the bottom of the cylindroconical fermenter. This is facilitated when the beer and yeast in the cone are cooled. Conduct secondary fermentation in the same fermenter. Some suspended yeast should exist in the beer, and therefore begin secondary fermentation when one to four million yeast cells per milliliter of beer exist. Also initiate secondary fermentation before all the fermentables have been consumed or add fermentables in the form of sugar or krausen (freshly fermenting young beer). The active yeast that is fermenting the residual fermentable sugar will metabolize compounds such as diacetyl during this period, causing the flavor to become more acceptable. Allow additional yeast and trub to fall into the cone over a period of time, depending on the type of beer that is to be produced. Allow about one week (perhaps only a few days) for ales and about two or more weeks for lagers. Dropping yeast removes a large amount of particulate matter, thus making filtration much easier and more efficient.
    • It may also be desirable to allow the beer to carbonate naturally during secondary fermentation, so it may be important to closely regulate the CO2 pressure that is exerted upon the tank and test the beer carbonation levels.
    • Age the beer if desired. Further condition the beer by aging it for extended periods of time. Use stainless tanks or oak casks. If making a beer such as a spontaneously fermented lambic, fruit may be added to the aging vessel. This will trigger an additional fermentation.
  28. Chill the fermented beer. After fermentation has been completed, cool the beer to prepare the beer for filtration. Ensure that the beer reaches {{safesubst:#invoke:convert|convert}} so that filterable haze complexes are formed, and that filtration is therefore as effective as possible. Cool the beer in the fermenter using the cooling jackets or with a heat exchanger. Use the heat exchanger in-line between the fermenter and filter.
  29. Filter the chilled beer. Maintain 28 to 30 degrees and filter the beer. This temperature causes chill haze protein-polyphenol complexes to form, which can then be filtered out. Use a diatomaceous earth (DE) filter (also called a powder filter) for primary filtration, and a sheet and/or membrane filter for additional clarity if desired. The filter that is pictured is a DE filter. As beer is filtered, the small tank holds a mixture of DE and beer that is dosed into a stream of incoming unfiltered beer and then into the larger tank. The larger tank holds metal screens that catch the DE and filter the beer. Piping and a centrifugal pump that occupy the lower area of the filter move unfiltered beer that is dosed with DE and filtered beer. The unfiltered beer moves in from a secondary fermenter, is dosed with DE in a chamber that doubles as a sight glass, moves through the filter elements in the large tank, comes out of the large tank filtered, moves past a sight glass, and is then directed into a bright tank. See substeps below for more information.
    • Use specific grades of diatomaceous earth powder for specific filtration duties to achieve the desired beer clarity. It is common practice to use coarser DE for the pre-coat, and finer DE for dosing. DE is mined from natural deposits and is the fossilized skeletons of microscopic algae, also known as diatoms. DE is sold as a fine powder. This forms a filter bed that is referred to as a depth filter. Depth filters create "tortuous paths" that small particles become stuck in, but the paths are actually wider than many of the particles that are filtered. Finer grades of DE are used to filter out finer particles and also to better remove the polyphenol-protein complexes that form chill haze. However, finer grades of DE lead to less efficient filtration runs.
    • Put on an N95 dust mask before handling dry DE powder, as DE can cause lung damage.
    • To begin filtering, first run some beer out of the fermentation tank and ensure that it does not contain too many particles, such as lots of yeast. This material will make filtering too difficult or impossible. Run incoming beer through a sight glass to make sure that it is filterable, and deter initial un-filterable material so that it does not enter the filter.
    • Begin filling the smaller compartment (the dosing tank) with incoming beer, and mix it with DE powder. Also fill the larger compartment with unfiltered beer.
    • The larger compartment contains flat metal screens that will catch the DE.
    • Under pressure that is induced by the filter pump and the subsequent flow of beer, the DE will form a filter layer or filter bed on the screens. The screens without a DE layer don't actually filter the beer. Circulate DE and beer through the filter so that a filter bed of DE builds up on the screens, forming the pre-coat. Beer will enter the two opposing outer sides of the screens, then flow into a thin middle section or chamber inside the screens and down to a small outlet in the bottom. From here, the filtered beer will flow through piping, past a sight glass, and either be recirculated or sent to the bright tank. The beer is initially recirculated.
    • As the pre-coat forms and creates a filter bed, the beer will become relatively clear. When this happens, the beer is ready to be transferred to the bright tank. Check the beer through the sight glass to make sure that it is of acceptable clarity. Look for DE breakthrough, and check the flow rate if possible.
    • Begin transferring filtered beer to the bright tank while adding continuous, regulated doses of DE from the dosing tank. Let incoming beer flow through the filter and run out to the bright tank. As filtering is conducted under pressure, and be sure to watch the pressure gauge on the filter. The pressure will climb as particles are trapped in the DE and as additional DE is added. However, dosing in new DE keeps the pressure from increasing too rapidly. The flow rate will decline as the pressure increases and filtering efficiency drops. However, if the pressure drops during filtration due to pumping failure, the filter bed can break free from the filter screens and the filtration must be started anew. As such, if the filter pump stops running or takes up pockets of air or other gas, the flow of beer on the filter bed will be interrupted and the filter bed may fall from the plates.
    • The DE filter bed with thicken until there is not enough space between the screens, and they run together. The screens should be pulled and cleaned of DE before this happens.
    • If the screens need to be cleaned, be sure to sanitize the filter again before filtering more beer.
    • Store the filtered beer in a clean, sanitized bright tank. Be sure to displace air in the bright tank with CO2 before filling so that the beer does not come into contact with oxygen and become oxidized. Prepare the bright tank for the filtered beer before filtering.
  30. Carbonate the beer in the bright tank. If the beer has not been carbonated naturally during secondary fermentation, or needs additional carbonation, use a carbonating stone to add a desired quantity (referred to as volumes) of carbon dioxide to the beer. For example, 2.6 volumes of CO2 may be desired. Alternatively, allow the beer to carbonate naturally with living yeast in the bottle. This generally requires that the beer be dosed with sugar or fresh wort. Beer can also be allowed to carbonate naturally in pressurized bright tanks prior to bottling.
    • Measure the carbon dioxide content of the carbonated beer before packaging. Use a testing apparatus to measure the carbon dioxide that is in the beer in order to be sure that it is completely correct.
    • Measure the oxygen content of the beer before packaging. It is informative to measure the oxygen content in the bright tank, as this is the end of the beer-making process. The beer is ready to be packaged at this point, and it is good to determine if it is within spec and read to be packaged. A high oxygen content is undesirable, as oxygen causes undesirable oxidation reactions.
  31. Package the beer. Bottle, keg, or can the beer for sale off-premises.
    • Keg the beer. Fill kegs with carbonated beer from the bright tank. If desired, use a flash pasteurizer to kill potential spoilage microbes in the beer before filling the kegs. Oxygen uptake is likely during this stage, and should be minimized by using packaging machines such as high-speed double evacuation bottle fillers. However, naturally conditioned beer that contains yeast is less prone to oxidation because the yeast rapidly consumes oxygen.
    • Bottle or can the beer. Bottle or can carbonated or uncarbonated beer from the bright tank. Uncarbonated beer that contains living yeast can be dosed with sugar or fresh wort and allowed to carbonate naturally in the bottle. Beer may be bottled using simple gravity fillers and $40 hand cappers or with more sophisticated machines, such as rotary bottle fillers. Try to keep the oxygen uptake low while bottling. If using simple machines, use beer that still contains living yeast, as the yeast will consume the oxygen as it is introduced to the beer. Yeast-free beer should be bottled with bottle fillers that evacuate the air from the bottle and replace it with carbon dioxide in order to prevent oxygen uptake. Beer can be pasteurized before bottling with a flash pasteurizer or after bottling with a tunnel pasteurizer. Naturally conditioned/carbonated beer cannot be pasteurized because the pasteurization would kill the yeast that produce the natural carbonation.
    • Box beer and stack the cases of beer on pallets. Wrap the pallets to make them ready for transport. Also put kegs of beer on pallets. If the beer is naturally conditioned/carbonated in the bottle, let the beer carbonate over a period of about two weeks before distributing it for sale.
    • Store beer that has already been carbonated (or that has finished carbonating naturally) in a cold room to preserve the quality of the beer until it is ready to be delivered.
  32. Evaluate the appearance of the beer. Check the color and look for particles, unwanted haze, and other desirable and undesirable factors.
  33. Taste the beer. Use a tasting panel, a flavor wheel, and other methods to evaluate the flavor of the beer. Be sure to taste for diacetyl and other compounds that may indicate improper fermentation or a microbial infection.
  34. Test the packaged beer. Use standardized devices to measure in-package carbonation, oxygen content, foam, haze or clarity, and other variables. Keep the oxygen content low to prevent unwanted oxidation. Maintain consistent carbonation levels. Test for bacterial contamination and other contaminants that may spoil beer and cause it to be aesthetically unpleasant. Use selective growth media to test for bacteria and wild or unwanted yeast strains.
  35. Deliver the packaged beer. Use a delivery truck to distribute the beer to stores and restaurants. Also use established distributors and importers who can deliver your beer to their customers in various locales, such as different states and countries.

Video

Tips

  • Centrifugal pumps can be run when full of liquid that is dead-headed or not moving. However, do not run centrifugal pumps dry or let them cavitate (run with air bubbles in the liquid).
  • Use brewery equipment that integrates well. Try not to fit together a hodgepodge of equipment that may not work well together and create production problems.
  • Properly size pumps and pipes with vessels and other equipment.
  • Do not try to fit too much equipment into one space. Breweries require a certain minimum floor space.
  • Different breweries use different types of equipment and brewing techniques. While the brewing methods used to make commercial beer are similar and follow the same principles and underlying science, there is no one ideal way to make beer, especially since there are many different beer styles.
  • Set up standard procedures that ensure a consistent product.
  • Start small and increase production along with demand.
  • Centrifugal pumps are generally not self-priming, so need to be placed at a lower level than the fluid to be pumped so that the fluid flows by gravity into the pump.
  • Use de-aerated water to pack brewery pipes and hoses that are used to transfer wort and beer to prevent the uptake of oxygen into beer. Water can be deteriorated by boiling or by using more sophisticated methods. The wort and beer will "chase" the deaerated water, or vice versa, and therefore prevent contact with air pockets or the introduction of air to vessels and equipment.
  • Hire an engineer to design an efficient, integrated brewery.
  • Maintain hygienic facilities at all times.
  • Except when aerating wort, keep wort and beer from coming in contact with oxygen, and therefore sealed from air. Wort and beer should not be allowed to become oxidized. This is especially crucial after beer has been filtered and separated from yeast, as yeast will consume oxygen. When yeast is absent, oxygen will merely accumulate in beer and cause an abundance of unwanted oxidative reactions.

Warnings

  • Caustic soda powder will cause an exothermic (heat-generating) reaction when added to water, and may boil over explosively when added to water. Do not mix caustic powder with hot or warm water.
  • Use earplugs when excessive noise exists, such as when operating a bottling line.
  • Carbon dioxide can cause suffocation.
  • Wear steel-toed boots, especially when lifting or working with hard, heavy items such as kegs.
  • Forklifts can cause serious injury, so make sure that you know how to properly operate them.
  • Be very careful when boiling wort, as the wort may boil over explosively. Wear a face mask and other protective equipment when checking the boil kettle.
  • Much brewery equipment is under high pressure. Ensure that vessels are depressurized and safe to work with.
  • Wear a high-quality N95 dust mask or respirator when handling dry diatomaceous earth.
  • Wear a face shield when pumping chemicals.
  • Brewery equipment and chemicals can be highly dangerous or hazardous. Only experienced personnel should brew beer.
  • Caustic soda and other chemicals must not contact skin, eyes, or any part of the body. Use chemical gloves, safety glasses or a face shield, a respiratory mask or gas mask (if needed), and other safety equipment when handling caustic soda and other chemicals.
  • Caustic soda absorbs carbon dioxide. This means that caustic soda added to a tank full of carbon dioxide can result in the sudden implosion of the tank.
  • Boiling water, hot water, and steam can cause serious burns.

Related Articles

Sources and Citations

  1. Brewing By Michael Lewis, Tom W. Young. ISBN 0306472740 (Accessed through Search Google for Books and Literature)