Tap beer should have a certain amount of foam at the top of its glass when served. This foam tingles the tongue and bursts forth tiny bubbles that are an essential component to a great glass of tap beer. Too much foam, though, is overwhelming and can interfere with the taste of your beer. If your bar or restaurant is having trouble keeping the froth to a minimum on their draft orders, here are two things that might be going wrong.
Too Much Nucleation
Beer foams by the process of nucleation. During nucleation, any rough surface can act as a nucleus. Dissolved carbon dioxide stick to the nuclei, form bubbles, and then rise to the top of the beer. The more nuclei a glass of beer has, the more foam it will form.
Tiny particles of barley in the beer usually provide ample surface area for nucleation to occur, but for those who want a little more foam, the glassware industry offers nucleated glasses. These glasses have etched surfaces inside the glass, thus providing more surfaces for those tiny bubbles to accumulate. While they do their job just fine, these glasses should be reserved for beers that are naturally low in foam.
When the glasses were ordered for your bar or restaurant, it's possible that whoever was in charge of placing the order didn't understand this process and unknowingly ordered nucleated glasses. If this is the case, switching to simple, non-etched glasses should solve your problem.
Furthermore, the water stains and/or tiny particles of detergent that are left on glasses after washing can provide unwanted nuclei. When you're serving beer, it's not enough to have clean glasses -- you need to have beer-clean glasses.
If you're already using etch-free glasses and following practices to make sure your glassware is beer-clean, then you may have particle buildup in your beer lines that is acting as nucleic points for foam to form. Your lines should be flushed between each keg, and, regardless of their condition, should be replaced at least every five years.
The warmer the temperature of your beer, the less able the carbon dioxide in it is able to remain dissolved. When this carbon dioxide comes out of solution, it turns into foam and rises to the top. Depending on the amount of particles each has (nucleic points), different beers will have different optimal temperatures. Check out the chart at craftbeertemple.com to determine what temperature the beers you serve should be stored at. If you find a discrepancy between the chart and your beer storage practices, adjust accordingly.
If you've already taken into consideration the correct temperature of the particular beers you serve, consider the state of your beer storage area. If you keep your kegs in the same cooler as other frequently used drinks or foods, the continuous opening and closing of the cooler door could be warming up the cooler and contributing to your excess froth problem.
It's best to keep your beer stored in its own cooler so you can control the climate with utmost diligence. However, if this isn't possible, consider installing plastic slats on your cooler door to limit the amount of cool air that exits the space and the amount of warm air that enters it. You can order these slats from any bar or restaurant supply store.
Froth is an important part of tap beer, but too much froth interferes with its taste and makes your customers feel like they're getting half-full glasses of beer. If the glasses of tap beer you're serving at your restaurant or bar have too much foam on top, then start your troubleshooting with the above two common reasons for big-headed beers. If you find that you need new lines, better glasses, or a more efficient cooler, contact a bar supplies retailer.Share