Then there are systems that are likely more familiar to bar patrons; the short and direct pour systems that use pure CO2 to push beer from kegs through lines, into taps and into a glass. These systems can include kegerators or kegged beer held relatively close to the tap handles.
There is the less desirable long-draw draft system where the beer travels a longer distance from the keg to glass. There is not only increased potential for contamination, but also cooling issues and increased beer loss that bar owners must contend with in using the systems.
It is not just CO2 that is used to dispense beer. Guinness, for example, uses nitrogen along with CO2 to get that signature effect in the glass and creamy taste. However, that mixture does not work as well with other beers and bar owners who cut corners trying to use the Guinness system on other beers quickly find themselves with under-carbonated lagers and ales.
“Put Bud on a Guinness system and within days the beer is flat,” says Jurado.
In The Glass
In conversations with brewers, industry professionals and even customers about carbonation, most brought up the Samuel Adams Boston Lager Glass, the result of two years of design and thought by the Boston Brewing Co. and Rastal Glass. With its bulb head and bottom curve for a person’s hand, the glass is nice to look at. It is the laser etching at the bottom of the glass, however, that was of particular interest to those interested in carbonation and overall flavor.
The laser etching is actually called a nucleation site. On a smooth glass surface, like the bottom of a shaker pint, there is no place for the carbonation to be released.