fb-pixelWhy does this beer taste bad? - The Boston Globe Skip to main content

Why does this beer taste bad?

Shaun Murphy, an employee of Tibs Taps, a company that installs and maintains draft beer systems, cleans out the tap lines at Boston Burger Company. Pat Greenhouse/Globe Staff

HAVERHILL — A rookie line cleaner disconnected a keg, dismantled the faucet and keg coupler, and connected the cleaning can to one of the lines that link kegs to taps at the AMVETS bar here. Sporting a pair of protective rubber gloves, he ran an alkaline solution through the draft line and began washing the disassembled parts with the same teal-colored cleaner, while his more practiced colleague narrated like the voice-over of a surgical drama.

It was a routine draft-line cleaning — the first stop on the men’s route through Northern Massachusetts. While the faucets air-dried, military veteran Shaun Murphy described the microscopic beasts that breed in lines left unchecked. “I can walk into a place and smell whether the taps are clean,” said Murphy, who since 2013 has been cleaning lines for Tibs Taps, a company that installs and maintains draft beer systems; he placed his fingers under the water that now ran through the lines, turning from green to clear as the chemicals dissipated.


Beer stone — comprised mostly of calcium oxalate molecules (a main component of kidney stones) — is a frequent offender in bad-tasting beer, offering safe haven to undesired microorganisms. Other usual suspects include the buildup of yeast and particulates, growing phenomena due to the surge in beer styles like weissbier and unfiltered IPAs, and the waning popularity of ultra-filtered lagers like the brands that star in Super Bowl ads.

Lactic acid, which produces yogurt’s tart taste, and acetic acid, found in vinegar, are common bacteria byproducts that can spread throughout draft lines, especially when bacteria-fermented sour beers like Belgian lambics are on tap.

While inspired craft brewers are known for their fondness for brewing with unusual ingredients, pints that taste like buttered popcorn or even latex paint could point to a bacterial infection in the draft system.


Most microorganisms that take up residence in draft lines do not pose significant health risks, thanks to the sanitizing effects of alcohol and CO2, but their impact on flavor concerns beer drinkers and brewers alike. Chuck Skypeck of the Brewers Association explained, “The issue is not about health, but delivering the beer to the consumer with the flavors and aromas the brewer intended.”

Not just a bad taste in your mouth

Jason Kerkoff, an employee of Tibs Taps, shows a keg coupler after it was cleaned of yeast buildup at Boston Burger Company.Pat Greenhouse/Globe Staff

Owner of Tibs Taps Mark Thibodeau says contaminants could indicate poor storage and sanitation habits on other fronts. Best practices warn against storing food and kegs in the same refrigerator, which can act as a breeding ground for bacteria and mold.

Unsanitary lines also pose a risk for craft breweries whose first (and possibly last) point of contact with the customer flows from the business end of a tap. Whereas beer conglomerates can survive the occasional off-tasting pint, smaller breweries have fewer shots at making a good impression. It’s a point that Thibodeau drives home to any customer who is hesitant about keeping to a regular cleaning schedule.

Like other professional line cleaners in New England, Thibodeau says most of his customers elect for one thorough cleaning every 30 days, though some business owners opt for more frequent services, like Dave Dalton, owner of Haverhill’s Grill Next Door. Dalton, who used to clean his own system until the 30-tap rundown started to overshadow his other restaurant duties, prides himself on his pristine draft lines. “A clean line . . . also allows the beer to pour properly with the proper head,” says Dalton.


“If you’re not willing to write off line cleaning, you shouldn’t be playing ball; you should be selling bottles,” says Thibodeau, whose business services more than 250 accounts from Maine to Massachusetts.

While rare, there has been at least one documented case in Massachusetts where a beer distributor failed to flush out the caustic cleaning solution from the draft lines, injuring a patron who suffered burns on her throat. Like the one that Tibs Taps uses, many cleaning solutions now contain color pigments to easily identify whether the lines are completely free from the solution before drawing beer from the tap.

Massachusetts law places responsibility on the bar or restaurant, rather than the distributor, for ensuring draft beer lines are clean and safe, but like similar laws in most states, the regulation is relatively unenforceable until an individual files a complaint or the business is subject to inspection.

Rules and best practices part ways

The Brewers Association recommends cleaning draft systems every 14 days, but warns that it is “not a magic number,” as cleaning is also contingent on beer style and storage habits.

State laws that regulate draft beer vary, and it usually falls on local health inspectors to enforce them. Massachusetts mandates that businesses clean their lines a whopping two times per week — significantly more than what most businesses opt for — while Connecticut mandates once per week, and New Hampshire and Vermont have no laws on the books that target draft lines. Few laws in the region regulate how or with what to clean draft lines.


Generally, a business that repeatedly violates the state’s liquor laws may face suspension or a revoked license, but the state’s liquor commission says they have never received a complaint specific to draft lines. According to Boston’s Health Division, if inspectors observe build-up on draft equipment, they’ll usually recommend that the business hire a professional cleaner.

Rhode Island requires that beer-serving businesses clean their lines once per month. The state used to require that anyone cleaning draft lines must hold a valid “line cleaner license” but removed the requirement last year as part of its deregulation efforts.

Both Connecticut and Rhode Island require that businesses keep logs of their line-cleaning services, so that inspectors may request them in case of a complaint.

While every two weeks is the industry standard, it’s not scientifically proven — at least not yet. The Brewers Association has set out to test the 14-day standard by studying the microorganisms that develop in tap lines and the effectiveness of various line-cleaning techniques. Results of the study are slated for release next year.

Currently, the best line of defense against consuming contaminated draft beer remains asking the bartender how often they clean their draft lines. “If someone at the bar can’t come up with a number in less than a minute,” says Thibodeau, “you might want to think twice about ordering.”

Cara Sabatini can be reached at carasabatini@gmail.com.