Mastering the Art and Science of Draft Beer: Tips for Optimal Yield and Quality Pouring

Whether you are serving beer at a bar, brewery, or out of a kegerator at your home, knowing the proper way to properly maintain and serve your draft beer is essential to pouring the perfect pint, and maximizing the yield from your kegs. Many commercial and home draft systems lose a large portion of their draft beer down the drain due to excess foam.  

With bottled beer, or cans, it is easy to control your yields. As long as you don’t spill the bottle, you get every bit of beer out of it. Draft beer isn’t so easily managed, you will never have 100% yield. Many bar and home keg systems only have a 70 to 80% yield on a keg.  

A number of factors can influence your draft beer yield: temperature, pressure, how and when your lines are cleaned and pouring technique. By controlling those factors, you can maximize the yield of your keg system.  

Temperature is one of the most important factors when serving draft beer. In fact, most yield and quality issues are temperature related. Your draft beer should be stored and served between 34⁰ F and 38⁰ F. Anything above 40⁰ F and your yields will drop significantly. The reason behind this is that temperatures above 38⁰ will lead to an increase in the amount of carbon dioxide released in the beer and create more foam. Above 40⁰ the amount of foam will increase to the point you’ll be pouring almost as much foam as drinkable beer.  

An important aspect in maintaining proper temperature is keeping your refrigeration well maintained and performing regular cleanings and maintenance on your draft coolers. A common cause of a keg box running hot and leading to foamy beer is that the condenser is covered in dust. This can be easily solved by manually removing the dust from the condenser, by removing the cover and blowing it out with some CO2.  

Bring your beer kegs down to the proper temperature after delivery and prior to hooking them up to your draft lines. A room temperature ½ barrel can take twenty-four to forty-eight hours to drop to the needed 38⁰ for proper service. Never put a keg that is not fully cooled to the proper serving temperature on your draft lines. 

Pressure will also impact how your beer pours. You control the pressure of your system by adjusting the regulator attached to the CO2 tank in most keg box systems or the wall-mounted regulator in the walk-in in most commercial long-draw systems.  

Too low a pressure will cause your beer to pour slowly, while too high pressure will cause your beer to pour too quickly, creating excessive foam. Having too high pressure for an extended period of time can actually cause your kegs to become overcarbonated, permanently leaving you with a very foamy keg that will never produce a proper yield. This can also hurt your drinking experience as the excess CO2 will cause bloating for the person enjoying the beer.  

In general, for a keg box, you want your pressure to be around 12.5 PSI, although the number of lines on your system, the length of those lines, exact temperature of the keg box, and other variables could change the optimal pressure for your draft system to run properly. If you have a long-draw system with especially long draft lines, finding the proper pressure can become even more difficult as you will need enough pressure to force the beer down through the lines, without overcarbonating your beer at the source.  

Regular cleaning of your draft beer system is also essential for maintaining a high yield on your draft beers. When you clean your lines, you remove old beer deposits that collect in the lines over time. These deposits can agitate your beer and lead to excess foam and can also cause your beer to take on off flavors. Having your own cleaning system and the proper tools will ensure that your draft system is always in proper working order and pouring the highest, best tasting beer possible.  

A final key to serving quality draft beer at high yields is pouring properly. The perfect draft pour starts with the glass roughly one inch below the faucet and held at a 45-degree angle. The faucet needs to be opened in one quick, smooth pull of the handle, which will ensure that the faucet opens fully and excess foam is not created. The glass should continue to be held at 45 degrees and straightened as the glass fills to prevent spillage. At no point in time should the draft faucet touch the beer or be inside the glass in any way. Pouring beers in this way will help to optimize yields and eliminate issues with creating excess waste.  

Whoever thought pouring a beer properly was both art and science? 

About The Bar Business Coach: The Bar Business Coach is a coaching organization focused on modernizing the way that bar and restaurant owners approach their businesses and helping them develop the tools and procedures to ensure excellence and profitability in their establishments.

Founder Chris Schneider has a degree in Hospitality and Tourism Management from Purdue University. Schneider has worked for more than 20 years in almost every position within nearly every segment in the bar and restaurant business, from fast food to fine dining. He has owned, operated, and managed multiple businesses, primarily focusing on the neighborhood bar segment. He believes that the synergy of tried-and-true methods combined with modern technology and data analysis are the keys to pushing the hospitality industry into the future. Schneider also has extensive experience in accounting, professional services, and customer service delivery that he leverages to help his coaching clients.