Guidelines for Using Vinyl Tubing in Draught Beer Systems

There are three locations on a tap system where it may be necessary to use vinyl tubing:

  1. Inside of direct-draw “beer boxes” where runs are six feet or less
  2. Inside of walk-in coolers as “jumper” line connecting the keg coupler to the trunk line
  3. Immediately before the beer shank and faucet as “choker” line to complete the required restriction rating for the system

Because vinyl is not considered a food grade material, the use of vinyl beer and gas lines should be kept to a minimum when designing and installing any tap system.

Vinyl tubing entered the draught beer industry as an alternative to copper and tin coils for short run direct-draw draught beer systems. The advantage is that vinyl is very flexible, unlike copper and tin, and it provides a restriction value similar to that of a copper or tin coil, therefore making it an ideal alternative to conventional coil systems.

Today, tap systems come in a variety of shapes and sizes, and the use of vinyl material has been implemented for both the added flexibility and as a convenient method of adding restriction to a system when necessary; but it must be noted that vinyl, as compared to copper, tin, and polyethylene materials, collects far more debris due to its porous, absorbent nature, and in order to maintain optimal sanitation within a tap system, the use of vinyl must be kept to an absolute minimum.   

Guidelines for Using Vinyl Tubing in Draught Beer Systems

Always use clear vinyl tubing so that contamination can be seen.

Direct-draw Systems

Direct-draw systems utilize 3/16” inner diameter (id) tubing for all beer line. The length of vinyl tubing used per line must match the desired restriction rating for the system. A standard American system dispenses beer at a carbonation rating of 2.5 – 2.7 volumes CO2 at a rate of 2 ounces per second (8 seconds per pint).

These dispense specifications are achieved only if the applied gas pressure, keg pressure, and total restriction rating of the system are each equal to 10 psi and the beer is dispensed at 35° F. Therefore, the appropriate length of each vinyl beer line may be determined by obtaining the restriction rating from the manufacturer, then dividing 10 psi by that rating. Most 3/16” id vinyl tubing has restriction ratings of 1 to 3 lbs/ft.

Example: If the rating is 2, divide 10 psi by 2 lbs/ft and the line length required to achieve 10 lbs total restriction is 5 ft.

Vinyl gas line should also be kept to a minimum. Most couplers are fitted with a 5/16” id gas inlet, so 5/16” is the practical size for gas line. One main gas line should run from the gas source to a manifold or T, and the manifold should be placed at a location that minimizes the length of gas line required to reach each coupler.

It’s necessary to keep the use of vinyl gas line to a minimum because vinyl, unlike metal and polyethylene, is gas permeable. This means that trace amounts of CO2 and N2 naturally escape through the vinyl material itself, thus incurring continuous gas loss. In order to minimize operating costs, vinyl gas line should be used sparingly.

Long-draw Systems

Long-draw systems are composed primarily of polyethylene beer line, but vinyl may be used as “choker” and “jumper” line at the front and rear of the system. Inside of a walk-in cooler, vinyl beer line may be used to connect each polyethylene line of the main beer line bundle to their respective keg couplers. For this application, 5/16″ or 3/8” id vinyl beer line is preferred. Vinyl will add a significant amount of restriction to the system; therefore, larger diameters are used in order to minimize restriction at the rear of the system.

Restriction must increase from rear to front, so that the flow of beer decelerates as it moves through the system and pressure is maintained. Remember, pressure is defined as resistance to flow. If restriction ratings decrease from rear to front, beer flow will accelerate, resulting in agitation, and pressure will be lost causing gas to separate from liquid, and subsequent foam at the faucet.

When installing vinyl jumper lines inside of a walk-in, there are three factors to consider:

  1. The height of the tap system
  2. The distance to the floor of the walk-in
  3. The restriction imparted by the addition of each piece of vinyl

Ideally, the highest point of elevation on a tap system will be the faucets. Beer in a tap system is pressure-driven, and the pressure originates at a gas source. Since gas is naturally lighter than liquid (at least in terms of CO2/N2 versus liquid beer), the gas in the system is constantly trying to rise—drawing beer with it. If at any location in a tap system the beer line peaks above the elevation of the faucets, gas will have a natural tendency to accumulate there, creating a gas pocket. When gas accumulations release, the result is “burping” or “bubbles” at the faucet.

Given an ideal setting upon installation, a tap system will be installed with the faucets being the highest point. So, when connecting vinyl jumper lines to trunk line, keep all jumper lines below the level of the faucets, as to prevent accumulation of gas within the jumper lines.

Once the upper end of each vinyl jumper line has been connected, the maximum allowable length of each line may be calculated by measuring the distance from the trunk/jumper connection to the floor, then subtracting six inches. This will provide space for the coupler to be connected without touching the floor when the jumper line is hung freely. Preventing the coupler from touching the floor is a sanitary measure that will avert microbial contamination of beer inside the keg.


Once the maximum jumper line length is determined, calculate the restriction that will be imparted based on length and inner diameter. Take this number into account, as it will be a critical figure in the overall restriction of the tap system. The restriction imparted by vinyl jumpers can be adjusted by altering the length and inner diameter of the vinyl line used.

portside-bar-walkinAlso, keep in mind that if jumpers are not all the same length, then restriction will vary line to line and equality must be re-established somewhere else in the system. Therefore, it is best to keep jumper line lengths consistent throughout the system regardless of the potential added convenience of lengthening jumper lines to reach kegs. JUMPER LINES ARE NOT EXTENSION LINES. Move the keg to the line. Do not extend the line to the keg. And keep all vinyl jumper line lengths to a minimum to ensure optimal system sanitation and to minimize gas loss.

Installing vinyl choker line is not always necessary, and most tap systems can be designed to avoid the use of choker. But if beer is pouring too fast or increased carbonation is desired, the addition of vinyl choker line is a simple and easy modification that will remedy flow rate and carbonation issues when all other factors are within specification.

By using 3/16” id vinyl tubing that has a restriction rating of 3 lbs/ft, the total restriction of a tap system can be increased without significantly increasing total line length. Choker line is placed directly behind the faucet and shank to slow pour rate and increase the volume of CO2 the system will retain.

Cleveland Beer Line Cleaning, LLC takes great pride in the customization of each tap system we install. Proper use of vinyl beer and gas line is a critical determinant in the resulting performance, sanitation, and efficiency of a draught beer system. By understanding the demands of each establishment, we are able to correctly design a system that suits our customers’ needs, and will dispense quality draught beer for years to come.

Want us to take a look at your tap system installation? Or do you need a tap system installed?

Contact us today >

Sensory Check Your System for Spoilage: See, Smell, Taste?

Performing sensory checks on your tap system is important for obvious reasons:

  1. To ensure the health and safety of your guests
  2. To maintain proper draught beer quality
  3. To check that your line cleaner is performing up to par.

A draught beer system that is properly maintained on a two week schedule should never fall victim to spoilage issues. But if it has been longer than 2 weeks since your system’s last cleaning, or if you feel that recent cleanings have not been fully effective, you can perform simple sensory checks on your tap system to locate sanitation trouble spots.

How to Check Your System for Spoilage

Keg Couplers and Faucets

cleveland beer line cleaning, dirty couplerThe most common points of microbial infection on a tap system are the faucets and keg couplers. These two locations are constantly exposed to open air where airborne bacteria, mold, and yeast will continually take advantage of beer as a nutrient source, forming films on sugar and protein residues that develop on these components.

If a keg coupler is infected with microbial film, it will be very visible. Simply remove the coupler from the keg and inspect for any slimy, moldy buildup around the seal and keg-coupler connection. If a microbial film is present, those microbes are certainly infecting the beer in your tap system as well, and immediate corrective action is required.

Couplers should be removed from kegs and soaked in soapy cleveland beer line cleaning, dirty couplerwater. Most of the film will fall off and the remainder may be scrubbed off using a small brush (toothbrush works well). To prevent future films from growing, couplers may be sprayed regularly with a simple antiseptic solution such as 50/50 rubbing alcohol (isopropanol)/water or 50/50 ammonia/water. These chemicals are strong antimicrobial agents that are safe to use as a no-rinse sanitizer on tap system components and will leave no flavor or aroma in the beer.

Beer faucets are of equal concern as they will spend their entire life exposed to an array of airborne pathogens and spoilage microorganisms. Faucets are made of food grade materials that inhibit the binding and growth of airborne microbes. But a poorly maintained faucet loses its antimicrobial properties when beer and foam is allowed to dry on the exterior. These dry residues are an cleveland beer line cleaning, dirty faucet residueopen invitation for microbial contamination. Airborne bacteria, mold, and yeast will quickly bind to these residues, metabolize them, and produce off-flavors and aromas at the faucet.

If there is any visible film on or in a faucet, it should be de-soiled immediately using a clean wet cloth and faucet brush. Faucets must be sanitized at the end of each shift using a simple chemical no-rinse sanitizer such as alcohol, ammonia, or an oxidizer.

To check for faucet sanitation issues, first observe the outside of the faucet for any dry beer residue and mold growth around the lever, plunger, and shank collar. Next check the inside of the faucet by rolling up a white paper napkin, inserting it into the faucet spout, then twisting and removing the napkin to see if any residue is being collected. If there is visible residue on the napkin, your faucets are in need of more frequent in-house sanitation procedures.

Next, sensory check for spoilage by smelling the napkin for a number of aromas that are often present. They are commonly described as having pungent characteristics of stinky feet, cheese, and vinegar. If you detect any of these odors, then common spoilage bacteria and yeast are present which produce acetic, lactic, and butyric acids that we associate with having these classic beer-spoilage aromas. Also, be sure to check faucet covers in the same way you checked your faucets, as these can be a site of infection (and re-infection) if not kept to the same sanitary standard as your faucets. Faucet covers should be soaked in sanitary solution when not in use and cleaned regularly using a faucet brush.

Drip Trays and Drains

Another common spoilage site is the beer drip tray and drain which are located just inches below the faucets. Your efforts to maintain clean beer faucets will be aided if a clean drip tray and drain is maintained. An infected drain will emit intense sour spoilage aromas, as well as provide a secondary site for bacteria, mold, and yeast to breed and produce future generations that will continually re-infect faucets and draught beer lines. Stale odors will be evident and residue buildup is usually visible inside the drain tube if drain cleaning has been neglected. Drip trays and drains should be flushed daily with hot water and can be stored overnight with a thick detergent inside to kill odors and prevent further microbial contamination.


Proper refrigerator hygiene is of considerable importance to the overall sanitation of a tap system. It is natural for spillage to occur in a walk-in refrigerator or beer box. It seems that every time a keg is changed some small amount of beer seems to seep out and find its way onto the floor. These tiny beer puddles aren’t even noticeable at first, but over time they will build up to create a major sanitation problem. Cold-tolerant bacteria, mold, and yeast breed on these beer residues left in refrigerators. Refrigeration will slow their growth, but it will never stop it completely.

Films of mold on refrigerator floors become especially visible if proper housekeeping procedures are not adhered to. One of the best investments for a keg cooler (other than the kegs themselves) is keg racks that hold kegs about 6 to 12 inches off the ground. This enables easy, continuous clean-up without ever having to move or lift kegs to mop under. By eliminating beer residue buildup inside keg coolers, airborne bacteria, mold, and yeast populations are significantly reduced, thus preventing these microbes from entering the lines.

Vinyl Lines

beer line cleaning, dirty vinyl beer linesIf exterior tap system components have experienced spoilage issues, then it’s likely the interior of the system contains spoilage microorganisms as well. Mold on keg couplers quickly makes its way into beer and gas lines. If your system was properly designed with clear vinyl jumper lines, then you will be able to see microbial deposits if infection is present. These deposits will appear as dark discolorations, solid films, and/or spots of microbial colonies.

You may also check for spoilage aromas in your gas lines by removing the coupler from the keg, moving the coupler handle into its down position (as if tapping a keg), and allowing for CO2 to flow from the coupler. CO2 has a refreshing aroma like the clean effervescence of mineral water. But if vinyl gas lines are contaminated, the CO2 will smell more like bad breath or a dirty locker room. Be sure to return the coupler handle to its up position to stop CO2 flow after inspection, as CO2 buildup in an enclosed area, like a refrigerator, poses a severe asphyxiation hazard.

Due to the highly porous and absorbent nature of vinyl materials, infections in vinyl lines are very difficult to remove, even with extreme chemical cleaning attempts. Tap systems are designed so that vinyl line replacement is easy and affordable. It is recommended that vinyl lines showing signs of infection be replaced immediately. By cleveland beer line cleaning, dirty fobdoing so, permanent sources of spoilage are completely removed from the system, providing a clean slate for fresh draught beer service.

If your draught beer system is equipped with foam-on-beer detectors (FOBs), this may be another site of infection. These devices are made out of plastic materials that, like vinyl, will absorb residues and off-flavors over time. These devices also create dead spots (points where flow is limited) in the system, which promotes the deposition and growth of microbial films. Check your FOBs for discoloration and film. FOBs must be removed from the system, disassembled, and scrubbed internally in order to achieve proper sanitation.

Observe the Beer

Finally, observe the aroma, flavor, body, and head retention qualities of beer served from your system. The beer itself should be the initial indicator of sanitary quality and the final confirmation of a properly maintained draught beer system.

The most profound analysis is offered in the first glass of beer poured from each line every day. This pint has sat in the line the longest and has had the greatest opportunity to pick up off-flavors and aromas. Pour this beer into a clean glass that is free of any sanitizer residue. Immediately after pouring, draw the aromatics of the first beer in through your nose focusing discretely on the malt and hop aromatic qualities. Both should be intense and uncompromised by any foul odors.

Next, set the glass down and allow the foam to settle. Clean beer served in a clean glass will maintain some head on the surface of the beer and some head will remain adhered to the interior of the glass as well.

Also, look for clarity in the body of the beer. Most filtered beer will allow light to pass through regardless of the color of malt used. A beer served from poorly maintained draught beer lines may be hazy and block light due to suspended solid sediment that is picked up within a dirty beer line. If your beer passes olfactory and visual inspection, then taste it. Bartenders and servers should be encouraged to regularly sample draught beer so that they become intuitively aware of the unique qualities of each beer, and will be able to immediately recognize spoilage issues.

Be sure to have your beer lines cleaned every two weeks, as recommended by the Brewers Association and the State of Ohio, and perform random in-house sensory checks to learn the quality of your system, the quality of the beer it is dispensing, and the quality of workmanship of the beer line cleaner you have hired.

Lastly, perform sensory checks because if you don’t, someone else will. And that person will likely be a customer (or multiple customers) who will either rave to their friends about your beer selection and the quality of service, or insist on never going back because their stout was skunky and sour.

How Beer Line Cleaning Can Increase Draught Beer Sales

Draught beer line cleaning is performed for two principal reasons:

  1. To achieve proper sanitation, and
  2. to ensure product quality.

Maintaining a clean draught beer system is essential for preserving the integrity and character of each beer. The most common reason customers choose draught beer over bottled is for the freshness.

For a draught beer establishment to earn customer loyalty, it must meet the expectations of its audience. Clientele who are passionate about their beers will keep coming back if service conditions are right. The most important of those conditions is, of course, draught beer quality through proper sanitation.

There are a number of indicators of poor sanitation; and most customers, either consciously or subconsciously, will identify these factors and build an opinion of an establishment based upon them. Obvious indicators include off-flavors, stale aromas, and a lack of foamy head which results from poor tap system sanitation.

The conscientious consumer pays great attention to product quality details, and this practice flourishes within the draught beer and craft beer communities. There is a simple way to earn the respect, loyalty, and repeat business of this vast market of consumers: Provide consistent draught beer quality through proper tap system maintenance and sanitation.

5 Ways to Ensure Beer Line Cleanliness

1.) Use Fresh Food-Grade Materials

Whether your establishment is utilizing an older draught beer system or if you are shopping for a brand new tap system, using fresh food-grade materials is paramount in ensuring proper sanitation and draught beer quality. Today’s standards in tap system materials are stainless steel and polyethylene plastics. If you are purchasing a new system, be sure that all metal fittings, faucets, and couplers are made of food-grade 304 stainless steel. Older systems will commonly have brass or nickel parts which can easily and affordably be replaced with stainless. On large “long-draw” tap systems, the “trunk lines,” which make up the majority of the system (from the cooler to the faucets), should be manufactured from polyethylene tubing and enclosed in a glycol-chilled insulated packing.

2.) Replace Vinyl Beer Lines

A smaller portion of the system, referred to as the “jumper lines”, will be made of vinyl flex tubing, which connects the trunk to the keg couplers inside of the cooler. Carbon dioxide and nitrogen beer gas lines will often be made of vinyl too. Vinyl is utilized for this application because of its flexibility and resistance to kinking; but vinyl is not considered a food-grade material and these lines should be replaced once a year. Vinyl, unlike polyethylene, has a highly porous surface that will harbor sugar, protein, and microbial deposits that can permanently infect a draught system; therefore, it is best to simply replace these lines on an annual basis.

3.) Routine Caustic Beer Line Cleanings Every Two Weeks

Routine caustic beer line cleanings performed every two weeks by a qualified technician will greatly reduce the risk of microbial infection that may result in beer spoilage and the transmission of food-borne illnesses caused by pathogenic bacteria, mold, and yeast. Caustic solutions of either sodium hydroxide (NaOH) or potassium hydroxide (KOH) destroy sugar and protein residues that build up on the interior of beer lines, and remove microorganisms that reside and feed on these nutrient residues. These solutions should be used at a pH of 12-13. All beer must be purged from the system.

The lines should then be filled with caustic solution, given at least 10 minutes to soak, then all cleaning solution must be removed and the lines rinsed with fresh tap water. The rinse water should be run until its pH matches that of the fresh tap water (6.5-8.5) to ensure all caustic solution has been removed.

4.) Quarterly Acid Cleanings

In addition to bi-weekly caustic cleanings, quarterly (every 3 months) acid cleanings must also be performed to remove mineral deposits. Excess mineral buildup will create a rough interior on polyethylene beer lines, thus negating its anti-microbial effects and rendering it useless for food and beverage applications. To avoid mineral buildup in a tap system, be sure that acid cleanings are performed under the same criteria as caustic cleanings, but with a cleaning solution of either hydrochloric acid (HCl) or peroxyacetic acid (C2H4O3) at a pH of 2-3.

5.) Visually Inspect System Components Daily

Bar staff should visually inspect and hand-clean tap system components every day, and beer faucets should be cleaned every shift. Faucets will accumulate visible sugar and protein residues inside and out, and must be sprayed with an organic solvent such as isopropyl alcohol (rubbing alcohol) to remove them. Faucet brushes are available for cleaning the inside of faucets. Keg couplers should also be checked regularly. When visible residue buildup occurs, these residues should be removed using a toothbrush. Tough residues can be soaked in alcohol or dish detergent to break and remove these sticky protein and sugar films.

By following these simple guidelines, any bar or restaurant can be assured that they are serving draught beer at its highest quality and keeping microbial contamination to a minimum. Be sure to discuss these procedures with your draught beer line cleaner to make sure you are receiving adequate service, and educate bar staff as to the importance of daily in-house tap system cleaning regimens.

Why Draught Beer Line Cleaning is Essential to Your Business

Tap system neglect is more common than most bar patrons realize. Many bar and restaurant owners are not aware of the importance of regular line cleaning and assume they can go longer than is recommended between routine cleanings. As a result, draught beer systems often fall into disrepair, and the owners wonder why so few people are ordering draught beer at their establishment.

Tap system neglect will quickly result in sanitation problems that distinctly affect draught beer quality and cause severe functional issues. Within only a couple weeks after cleaning a tap system, beer lines, faucets, couplers, and foam detectors accumulate noticeable amounts of solid beer residue, or “beer scale.” These residues harbor bacteria, mold, and yeast, and cause moving parts to stick together and quickly malfunction. Routine cleaning (once every two weeks) will prevent these microorganisms from permanently infecting the system, while ensuring precise, dependable function of the entire tap system.

A poorly maintained tap system can fail any number of ways. Faucet, coupler, and foam detector valves collect sticky residues that prevent them from fully opening and closing, thus resulting in leakage. If the system is leaking beer, this leakage point also provides an entry point for microbial infection that will cause beer spoilage and undesirable souring.

Faucets will also “freeze up” as a result of dried sugar residue that essentially “glues” the internal parts of the faucet together.

Slow drip tray drainage is another common problem. If drains are not flushed daily with sanitizer they will fail, resulting in backup and overflow during high volume service. The backup is caused by an accumulation of sugar residue inside the drain tube, which also grows films of mold, yeast, and bacteria, as well as attract fruit flies.

These are just a few examples of why it is important to maintain the sanitary quality of a draught beer system. Routine cleanings performed by an experienced draught beer technician will prevent sanitation problems and alleviate most functional issues.

Need help with your tap system? Contact us today: 216.533.7936.

How You Can Tell if You’re Drinking from a Dirty Beer Line


We’ve all been there before. You sit down at your favorite bar, order a draught beer, and take the first sip. Only something doesn’t taste quite right. It tastes . . . dirty. Or flat. Or simply horrible. But what does that mean?

First, some of the characteristic indicators of a “dirty” beer line are the same for “dirty” glassware. These indicators are:

  1. Quick loss of head retention
  2. Lack of legs forming and remaining on the inside of the beer glass
  3. Seemingly flat beer due to rapid loss of carbon dioxide gas

All of these factors are related, but they can be the result two unrelated causes—a dirty beer line or dirty glassware. So let’s clarify the difference in terms of “dirty.”

Defining a Dirty Beer Line

The State of Ohio describes a “dirty” beer line as one that has not been kept in compliance with Ohio Administrative Code 4301:1-1-28: Beer and wine: cleaning and sterilizing dispensing apparatus. Although this code goes into no detail about how lines should be cleaned, what methods and chemicals should be used, or what the actual risks to the consumer are if beer lines are not kept to standard, it does state that line cleaning must be performed “not less than once every two weeks.” Therefore, by Ohio law, a “dirty” beer line is one that has not been cleaned by a registered line cleaner in over 14 days. How would you know this? Simply ask to see a bar’s line cleaning log. By law, all bars must maintain a log of their line cleaning, which will be initialed and dated by an Ohio registered line cleaner every time line cleaning is performed.

So how is “dirty” different from beer line to beer glass? A dirty beer line will have sugar and protein residue built up inside. These residues may break off when agitated by the flow of beer, resulting in chunks or flakes in the dispensed beer. This is an ugly surprise to the beer drinker, and quite embarrassing for the bartender and bar owner. Even worse, these pieces of beer solids harbor films of bacteria, mold, and yeast that will quickly spoil the beer once colonies are established inside the line. Even if beer flakes are not dispensed into the glass, be assured that residues do exist in the lines of unkept tap systems, and microbial biofilms harbored by these residues will taint the flavor of draught beer, leaving a sour or dry, cardboard-like taste in the beer, along with a loss of malty sweetness. It is mainly a variety of acids that are detected as off-flavors when sipping a beer that has been spoiled by a “dirty” beer line. These acids also break up the foamy head of a beer, wash those sticky beer legs from the inside of the glass, and expedite the release of CO2 from a once sparkly beer. If you think you’re detecting any of these off-flavors, or if you make any of these visual observations, then you’re probably drinking from a dirty beer line.  

Defining a Dirty Beer Glass

It is important to note that these same visual observations may also be made if clean beer is dispensed into a “dirty” glass. The flavor quality and sanitation of the beer will NOT be effected, so be careful before drawing any conclusions as to the cleanliness of the tap system. A “dirty” beer glass is any glassware that does not permit full contact of beer and glass. Beer sugars and proteins bind to glass resulting in full head retention and beautiful scaffolding of legs on the glass’s interior throughout the life of a pint, no matter how long or short that time may be.

So what could possibly get in the way of foamy head structure and leg formation on a glass’s interior? Well, anything else that sticks to glass. Sanitizers today, such as iodine, are designed to do just that in order to form a sanitary barrier between the glass’s surface and any potential airborne pathogens. This is great in terms of preventing the spread of foodborne illness; and this modern theory and methodology has been applied to all sectors of the food and beverage industry. Plates and silverware receive the same type of sanitary treatment, but the quality and presentation of food is unaffected by this. Rather it’s draught beer service that falls victim to modern sanitation methods.

If you suspect that sanitizer residue is killing the head on your beer, then ask the bartender to re-use your glass. Normally, a good first coat of beer on the inside of your glass will wash away sanitizer residue (consuming iodine will not hurt you) while laying a foundation for excellent head retention on your second, third, fourth . . . or fifth beer. If you notice improved head retention the second time around, then sanitizer was the culprit. Not a “dirty” beer line. This is more common than you may realize.

The second form of a “dirty” beer glass is one that is truly dirty. If it was washed with dirty water it will have an oily or greasy residue coating its surface, which repels water-based solutions like beer. This commonly results when bars do not change their wash-and-rinse water out frequently enough. This is also very common. Watch for a bartender’s or bar back’s attention to detail when running glasses through wash and rinse sinks, and also notice if glasses are being polished with a dry towel after washing and drying. The most important reason to polish is to remove any potential residues that will destroy the integrity of a quality draught beer.

In conclusion, if you order a familiar beer and it tastes and smells right, it is likely that you are drinking from a clean draught system. If you’re in doubt, look for visual indicators. And if you truly believe you’ve been served beer from a dirty beer line, ask to see the bar’s line cleaning log. Check that the date of their last cleaning is within two weeks. The date will be followed by the line cleaner’s initials and his or her 8-digit Ohio registration number.

Have any questions? Contact us today!

How to Maintain the Highest Quality Draught Beer

There are three factors that need to be optimized to ensure draught beer is at its highest quality—sanitation, refrigeration, and carbonation. All factors are equally important in terms of “quality,” but from a safety standpoint, sanitation is paramount.

A Technical Snapshot: How Beer is Made

The best way to imagine what it takes to maintain the integrity of draught beer is to consider the conditions under which beer is produced. This includes everything from mashing and boiling to fermenting and carbonating. Grain is mashed in water to release enzymes that produce simple fermentable sugars (maltose and glucose) for yeast to consume. The sugar water is then boiled to kill microorganisms (wild yeast, mold, and bacteria) while simultaneously adding hops to acidify and season the beer.

Historically, the acidity of beer along with the alcohol produced from fermentation was believed to prohibit microbial growth in a finished beer. While these attributes do inhibit bacteria, mold, and yeast, they do not prevent all microbial strains from growing. For this reason, most beers, with the exception of certain conditioned beers, are refrigerated immediately after fermentation is complete.

The Importance of Refrigerating Draught Beer

The general range of recommended refrigeration temperatures for beer is 30-39°F. Maintaining beer within this temperature range is important for four reasons:

  1. Bacteria, mold, and yeast are believed to be inactive at temperatures below 40°F.
  2. The ability of liquid beer to retain absorbed carbon dioxide gas changes drastically as the beer heats and cools.
  3. Oxidation (staling) occurs in beer more rapidly at higher temperatures, thus decreasing shelf life.
  4. Beer expiration dates are based on the assumption that the beer will remain at temps below 40°F from the distributor to the retailer to the consumer.

Consistent refrigeration is essential for maintaining the intended quality and character of draught beer.

The Importance of Cleanliness in Draught Beer Quality

Once a keg is tapped, the beer leaves the sterile environment within the keg and is exposed to a variety of factors that may compromise draught beer quality. Sugar and protein residues that are not consumed by yeast during fermentation serve as “leftovers” for other microorganisms to consume. These microorganisms are mainly airborne bacteria, mold, and yeast that will adhere to any surface that offers nutrient value (i.e. unclean beer faucets). Maintaining beer faucets that are free of dry beer residue (sugars and proteins) is the most important step bar staff can take to ensure proper sanitation of a draught system between routine line cleanings. When bacteria, mold, and yeast enter a draught beer line they continue to feed on the available nutrients in the beer, and their byproducts will alter the flavor and quality of the beer.

Inevitably, all draught systems will fall victim to microbial infection. Again, this is one reason why maintaining proper refrigeration temperature is so important. Refrigeration is crucial for maintaining proper carbonation and pour rate as well, and if you own an establishment that sells draught beer, then foamy beer equals lost profits.

The Importance of Beer Carbonation in Draught Beer Quality

Beer carbonation is measured in specific units called “volumes CO2,” and this volume is set to a specific rating by the brewery at a specific temperature prior to kegging the beer. Because the absorption of gas (CO2) in a liquid (beer) changes with temperature change (Henry’s Law), refrigeration temperatures must be kept constant to ensure the carbonation rating is consistent with the rating set by the brewery. If beer temperature is increased (above 39F), less CO2 remains absorbed by the beer, resulting in increased foam.

Choosing the proper gas blend for your system is also a critical determinant of carbonation and flow rate. Carbon dioxide/nitrogen (CO2/N2) gas blends became popular as the sizes of tap systems increased. The N2 content pushes the beer through the beer line while the CO2 is responsible for maintaining the proper carbonation rating.

In general, draught beer carbonation can be maintained by the retailer by pressurizing kegs in the same manner that a brewery uses to set the initial carbonation rating: using 100% CO2 at 10 psi (pounds per square inch) within the correct temperature range. This will maintain a desirable carbonation level while also balancing the keg with the restriction value of the beer line (induced by friction and gravity), resulting in just enough pressure to drive the beer to the faucet without over-carbonating the beer while maintaining a desirable pour rate.

That said, larger tap systems will often have restriction values too great and the keg cannot be balanced with the line using only 10 psi. In other words, 10 psi will not be enough pressure to deliver the beer from the keg to the faucet if the total line restriction (between the keg and faucet) is greater than 10 pounds. This is why additional pressure is applied with the help of nitrogen, an inert gas that is not readily absorbed by beer. Selecting the proper gas blend for a particular tap system requires knowledge of the system’s line restriction rating, static pressure, atmospheric pressure, and elevation.

Unfortunately, many bars today simply run a generic 50/50 or 60/40 (CO2/N2) blend instead of making the additional effort to determine the gas ratio that will correctly match the system to brewery-specified carbonation levels. Find a qualified draught beer technician who is willing and able to do this.

Carbonation, refrigeration, and sanitation issues are common, and usually result from poor maintenance or a lack of attention to detail during installation. Industry professionals should perform routine inspections, which can save the retailer thousands of dollars annually, especially when foaming issues are corrected. Equally important, the retailer must respect specifications and quality standards set by breweries, and take any measures necessary to ensure that only beer of the highest quality and integrity is served to their customers.

The consumer should expect nothing less.

Do you need help maintaining the highest quality of draught beer? Contact us today >