The process of industrial beer kegging holds interesting lessons for the home brewer as well as owners of home draft systems. The kegging systems of large brewing operations are intended to distribute thousands of gallons of beer. Meticulous machinery ensures a fine, clean tasting product will pour forth from draft taps the world over in a timely manner. Most, but not all commercial beers are pasteurized in the keg, ensuring that no unwanted bacteria or yeast changed the flavor of the beer after it leaves the brewery. Understanding the industrial process of kegging beer can help you to understand your own kegging operations, weather they be kegging your own home brew or simply hooking up a store bought keg to your keg cooler.
|Source: HomeBrewing.com Archives|
By looking at the industrial process of beer kegging, home brewers and brew pub owners can more easily come up with practical solutions to utilizing kegs for smaller scale beer production. One lesson that can be taken from the bigger beer manufacturers is to hold on to your kegs! Thefts of beer kegs from porches and behind liquor stores are causing a lot of hassle and needless cost for industrial beer manufacturers.
According to Pacific Business News, approximately 300,000 stainless steel kegs are stolen in the U.S. each year.
So hold onto those kegs - maybe with a padlock if you have to keep them outside. Otherwise, your keg might end up at the scrapyard.
The industrial beer kegging process starts with re-use. Empty kegs are returned to the brewery from the bar, usually via the beer distributor. The kegs returning may, at times, have stale or tainted beer in them, so they need to be cleaned out thoroughly. This process starts with removing and cleaning the Sanke valve. This is the point at which home brewers and brew pub owners must look at what resources are available for them. The giant, expensive machines used in industrial beer production simply are not practical for smaller scale breweries. A Sanke valve extraction kit is a necessary investment for brew pub owners. Home brewers can usually get by without the $250 tool by using pliers, screwdriver, and hammer. That is, until they tire of the bloody knuckles and broken parts.
It is vital that the Sanke valve is removed for cleaning the keg, and also, the "spear". This is the part of the keg that shoots down to the bottom of the keg for the purpose of jetting the beer out of the keg. The inside of the keg must be inspected and scrubbed. Soaking the keg in high temperature water is helpful. I have known home brewers who simply fill the keg with water and boil it for an hour or so to clean it. Caustic solutions can be helpful for getting off stubborn sediment. The most helpful hint for cleaning kegs seems to be this: clean kegs in a timely manner. The longer one waits, the more likely some bacterial taint or sedimental sludge will cause you grief in the cleaning process.
During the sanitization process, it is important to realize that using bleach to clean stainless steel is a bad idea - it can cause corrosion on the stainless steel if chlorine is left in contact with the metal. The industrial kegging process uses steam heat, possibly with chemicals added as well, for this stage. Sanitization is best done just before the kegs are to be filled. This gives the "bad guys" (i.e. bacteria, rogue yeast, etc) the least amount to time to keg into your keg and your brew. Cleaning right away is a good idea, but after the kegs have been scrubbed, wait for a thorough sanitization until the next beer is ready to be kegged. At this point, it is advisable to soak the kegs in an iodophor solution, rinse them with cold water, and then purge the air out by displacing it with CO2. Now the keg is ready to be filled with beer!
Industrial beer kegging operations have the benefit of being able to pasteurize their beer, ensuring that the beer will taste at the bar as it did when it left the brewery. Smaller scale brewers, and craft brewers, do not have this luxury, and so must have a firm comprehension of how beer changes over time. Beer must have the right yeast and the right sugar ratio to achieve what the brewer is aiming for.
The kegerator, or draft beer dispenser, must also be given the same care and attention to cleaning as the keg has. If not, tainted beer lines may ruin the fine job of cleaning and sanitation that has been employed upon the keg. Beer line cleaning and sanitation kits should always be used in between kegs.