Don’t Let Dirty Draft Lines Ruin Your Beer

The beer-making process is complex. There are a lot of opportunities for mistakes, up to the very moment when the beer goes through the draft line and into a glass. It’s why keeping lines clean is crucial for any brewery, bar, or restaurant that values the quality of their beers.

“Beer lines are the very last point of contact and the last point where something can go wrong,” says Michele Wonder, a Certified Cicerone and draft services professional with Perfect Pour Services in Portland, Oregon. The company helps install, clean, and maintain systems for commercial and home clients.

“These brewers have worked exceedingly hard to ensure that the flavor of their beer and the integrity of their product is at the maximum, and it can really fall down on that last leg,” Wonder says. “A lot of brewers understand that, and a lot do not.”

Why Is Draft Line Cleaning Important?

A dirty draft line won’t kill your customers, but it will kill your reputation. That’s because the alcohol will eliminate harmful bacteria that will make you ill, but the unclean lines can dramatically affect flavor.

No matter how diligently a delicious beer is brewed, if it’s poured through a bad line, drinkers will notice. Lines are made of vinyl tubing. The porous material is subject to bacteria build up, which often results in a vinegary, acidic taste. Diacetyl can also accrue in a dirty line. The acid has a buttery flavor that creates a slick texture.

“It’s just going to taste nasty,” Wonder says. “It tastes like old gym socks.”

Signs of a Dirty Line

Besides unwanted funky flavors, another indicator of an unclean line is a darkening opaqueness of the vinyl tubing. Buildup on external parts are other clues to look out for; grime on the faucets and the keg couplers are signs that cleanings are overdue.

How Often Should You Clean Draft Lines?

When it comes to line cleaning, the Brewers Association’s free, downloadable Draught Beer Quality Manual “is the Bible for draft cleaning,” Wonder says. The manual suggests a full line cleaning every two weeks. Wonder has customers who schedule every four weeks. Smaller customers, such as offices, might wait every eight weeks. However, she says that any commercial business should not surpass the four-week mark.

“People wish that frequency of service was based on quantity of dispense, but that’s not the case,” she said. “There is product in the system, whether it’s sitting there or whether it’s used on a regular basis.”

The Draught Beer Quality Manual suggests replacing lines every 12 to 18 months. BYet Wonder says that when regularly maintaining the lines, they can last up to two to three years.

Customers also should be aware that the price of their bill isn’t an indicator of whether or not a business prioritizes maintenance.

“We have lots of dive bars that clean on a very regular basis. I definitely know of some high-end places that do not clean at all,” she says. “Some of the finest five-star restaurants have the scariest kitchens you’ve ever seen.”

How to Properly Clean Draft Lines

Wonder says the optimal way to clean lines is with mechanical action—pumps that achieve better circulation and flow rates. Homebrewers can get away with pot soaking, pumping chemicals into the line and letting it sit in a bucket of solution. Wonder says that all commercial businesses should be using the mechanical-action method:

1. To start, uncouple all the kegs. Use a towel and bucket to make sure no product gets on the kegs and the cooler floor.
2. Drain all the beer from the system.
3. Take a cleaning coupler and attach line No. 1 to one side of the coupler and line No. 2 to the other side, and create a loop in that line. If you have a four-line system, use another coupler that connects lines 3 and 4.
4. Remove the faucets with the spanner wrench. Disassemble the faucets and soak them in a bucket with PBW Liquid (alkaline safer cleaner) or Liquid Circulation Clearner (LCC) caustic solution.
5. Set up the mechanical pump. Put the input part into a bucket of water first. Connect line No. 1 to the first position in the tower.
6. Add a jumper line that connects line 2 to line 3 and an outlet hose connected to 4. Begin pushing clean water through the system with the outlet hose draining into a sink or drain.
7. Continue cycling until there is nothing but water going through the system.
8. Now flush the line with PBW Liquid or LCC. Caustic solutions have specific dosing. The brewers manual suggests caustic solutions as the best practice for line cleaning, but Wonder says many people prefer using Powdered Brewery Wash (PBW). “It’s aces, I love it to death,” she says. “I use it all over my house, I use it all over the brewery. It’s a lot more environmentally friendly. It doesn't have the need for such precision in dosing and can be handled by people with a lot less chemical experiences.”
9. Once ready, run the solution through the line until the output runs clear. Then you can begin recirculating the cleaning agent throughout the system by moving the output hose from the sink or drain into the bucket of cleaning solution to form a loop.
10. While the circulation is happening, brush all the components, visually inspecting the soft parts like the coupling gaskets for wear and tear. Replace parts as needed.
11. After the solution is finished cycling, flush with multiple buckets of warm water to ensure no residual cleaning solution is left in the system.
12. Reassemble the system.
13. Once retapped, pull all the water in the line through the tap until beer flows.
14. Cheers!

The Sins of Draft Line Cleaning

Anyone cleaning draft lines should be aware of these common mistakes:

1. Not recirculating for a long enough time.
2. Not using the correct temperature of the cleaning chemicals. Water with PBW needs to be 120°F (49°C) and above to be used most efficiently. Recirculating at that temperature isn’t necessary, but hot water is needed to mix the solution.
3. With caustic, the number one issue is inaccurate dosing. Wonder says a titration test to see what percentage the solution is at is ideal for caustic. She has seen many professionals run way more or less than they need.
4. Not giving enough time and attention to faucets and the couplers is another no-no.
5. Using inferior hardware such as brass and copper plating. Stainless steel will pay for itself in the long-run, she says.

Wonder also suggests keeping a cleaning log to have some sort of record and accountability. She hopes that one day draft-line cleaning will be as transparent as health department scores. The transparency will encourage everyone to maintain their systems and keep beer safe and delicious for customers.

“If you’re a brewer, remember that this is the last thing that touches your beer. This is the last thing that can mess up your beer,” Wonder says. “It’s super important, and beer drinkers are becoming much more aware of this. It’s something you can’t take a shortcut on.”