Uncovering the Science of Draft Beer, from Proper Glassware to Cleaning Techniques

Draft beer is the brewers’ gold,” a bar owner once told me, meaning draft beer — unpasteurized, shipped cold and served cold — was the closest thing you could get to beer right from a brewery’s tanks. Well-kept draft beer, served cold and fresh, is the backbone of a successful beer program. You need to protect your draft beer from things that will tarnish that brewers’ gold.

Server Basics
The first part of a good draft program is the most basic: learning to pour. It starts with the glassware. Whatever you use, the glasses should be “beer clean,” not touched by soap, which will kill the foam. Use a glass detergent, a rinse agent and lots of rinse water. You may want to rinse each glass with a cold water spray (the Spulboy washer is great for this); this makes a good pour even easier.

Now take the tap handle: Grasp it at the bottom, not the top, and you’ll have more control (some long handles can give enough leverage to snap the shank if you pull from the top). Open the tap all the way in one smooth motion, not a jerk, and close it the same way. This allows the beer to flow at the set volume, and it doesn’t constrict the flow, which causes the beer to foam.

Train servers not to do the “waste pour,” where they open the tap before they put the glass under the stream of beer. It’s wasteful, it takes extra time, and it’s not necessary; it’s just a bad habit. Experienced bartenders may do it as well, and you’ll have to convince them to change.

Don’t put the nozzle against the glass; it shouldn’t touch the beer. It may be faster — you can pour two beers at once that way — but it’s not sanitary and it can cause glass chips and breaks. Open the tap with the glass tilted about 30 degrees, and as the beer comes to the top, smoothly tilt the glass upright and finish with an inch of foam. Foam looks good, releases aromatics, keeps beer from spilling on the way to the table and is profitable, as foam is only 25 percent beer.

So now you have a good beer in a clean glass. Finish it by presenting it to the customer. I don’t like napkins, but I do like a coaster. Just placing the glass on the bar leads to liquid — condensation or spilled beer — on the bar, which is an unnecessary mess.

If you’re pouring and the keg empties, the server should know what to do, but don’t just assume they know how to change a keg. Train them on how to find the right keg in your coldbox (which means it’s a good idea to label or number your draft lines at both ends), disconnect the old one and put it aside for return and connect the fresh one.

If you’re using FOBs (see sidebar), reset the FOB. That’s about it for basic knowledge on serving draft; what’s next is what to do when things go wrong.

First, Do No Harm
Every bartender should know when there’s a problem beyond an empty keg; almost every problem will present as foaming. But you must have someone at your operation who knows how to fix these common problems. Ideally, you’ll have an expert who can then train at least one backup person.

“We have designated people that I’ve trained for small emergencies,” explains Casey Hard, manager at Max’s Taphouse in Baltimore where he oversees 144 taps, ranging from Miller Lite to vintage kegs of Cantillon Lou Pepe lambic. “If I’m there, I do it, and I trained three or four people to do some easy [repairs]. You need to train someone in the terminology, and then create a checklist of things. If you go through the checklist and it’s not fixed, shut it down and call the expert.”

Indeed, if working through the checklist doesn’t work the magic, an expert is the only  person you want handling the problem … you want everyone else to leave it alone. When beer isn’t pouring right, it’s almost always a problem with temperature or the actual keg, yet the layman’s first reaction is to change the gas pressure. That’s the first rule of fixing draft problems: If you don’t know what’s going on, don’t touch it.

Hot and Cold
The problem usually is not the keg itself. Often the problem is temperature; either your line or the keg is too warm. (That’s why Hard keeps all his kegs refrigerated from the time they’re delivered.) When beer warms up, even by a few degrees, gas will break out of the solution and create foam in your lines. That means wasted beer and wasted money, pouring foam down the drain (25 percent beer, remember) and taking way too long to pour one glass.

Ensuring consistent temperature — about 38 degrees Fahrenheit — from the keg to the glass is a key to good draft dispense. Whether you use forced air or a glycol system to achieve it, you must maintain and check that system.

Temperature is important in another place: your glassware. You’ve probably heard the arguments for and against chilled glasses, and it’s simple: If you have frosty glasses, your beer will be watered down and foamy. But you don’t want to serve beer in glasses just out of the dishwasher; hot glasses, even warm glasses, will make foam break right out of the beer and make a good pour very difficult. To frost or not to frost, that’s a choice you have to make, but ensuring glasses are not warm is an absolute must.

Keeping it Clean
Just as important as correct temperature and pressure is cleanliness. Your draft lines should be cleaned every two weeks — more, if required by law — and that means you’re either using a service or buying your own equipment. Either way, you should learn what’s going on so you know it’s being done right. You’ll want to brush-clean all the taps, too. Cleaning’s also a great time to check valves, lines, seals and clamps for leaks and cracks.

Cleaning lines means losing the beer that’s in the lines, but that’s part of the cost of business. If you don’t clean, you’ll have beerstone, bacterial growth and foul-tasting, foamy draft beer, which will cost you much more in lost sales. Clean, fresh draft should be a selling point for your operation.

“We clean our taps every time we change a keg,” Hard says. “Not when it’s the same brands, but if a new beer comes on, we flush the whole line.” That’s on top of the two-week cleaning cycle; if you want to be a beer bar, he notes, that’s just part of the process.

The last step? Quality control. “I taste every beer when I tap it,” Hard says without any irony, “and I date my kegs. I don’t keep anything on more than a month, and 98 percent of the time, that never happens. If a customer says a beer’s bad, and it is, I take it off right then.”

Keep the lines, taps and glasses clean. Pour smoothly without touching the nozzle to the beer, with an inch of head, and don’t waste beer. Fix it if you can, but know when to call for help. Just do that, and you’ll be serving brewers’ gold. NCB

Walk the Talk

Here is a primer on terms and things you need to know about your draft system.

•    Beer gas – A blend of carbon dioxide and nitrogen, used for nitro-dispense beers (like Guinness) and for pushing beer through long runs without over-carbonating it.
•    Beerstone – Mineral deposit (calcium oxalate) that can occur in draft lines and spigots; creates turbulence and harbors microorganisms.
•    Blender – A device that mixes beer gas on-site from bulk tanks and accurately delivers proper pressures, reducing waste from foaming.
•    CO2/Carbon Dioxide – Beer’s “normal” gas, used to push beer through short lines and keep the beer carbonated.
•    Flowmeter – Measuring device connected to draft lines to track amount of beer dispensed (and accounted for in sales).
•    FOB – “Foam On Beer,” a float valve that shuts off a draft line when a keg empties, leaving the line full of beer. FOBs save beer and profits.
•    Forced Air Cooling – Chilled air from the cold box forced through short- to medium-length draft lines to chill the lines.
•    Glycol – Refrigerating liquid used in recirculating systems to chill long draft lines and towers.
•    Lift – The vertical distance between the keg and the tap, used to calculate pressures.
•    Nitrogen – Gas used mainly to push beer through long lines; nitrogen will not readily dissolve in beer, and so will push without creating a “Guinness effect.”
•    Pump – Compressed gas-driven pumps are an alternative to gas pressure to push beer through long lines.
•    Regulator – Valve to set and change gas pressure in a line or the whole system. Crucial to successful draft dispense.
•    Run – The horizontal distance between the keg and the tap, used to calculate pressures.
•    Spigot – The actual mechanism of the tap.
•    Tower – A freestanding single tap or collection of taps, usually chilled by glycol or forced air.

Knowledge on Tap at Nightclub & Bar Show

At the Center for Draught Excellence on the exhibit floor at the Nightclub & Bar Convention and Trade Show in Las Vegas, you can get first-hand experience and expertise on profitable pours. On March 9 and 10, Anheuser-Busch, Micro Matic, NuCO2 and TapDynamics will present a multi-faceted view of dispensing, equipment and server strategies to maximize the draft beer opportunity in your establishment. Be sure to stop by!

Look for more coverage of draft beer best practices in upcoming issues of Nightclub & Bar and online at www.nightclub.com:
• April/May – Beer Style Guide
• June – Powerful Beer Promotions
• July – Specialty, Seasonal & Craft Brews