By Triana O'Keefe, editor Australian Hotelier
When poured, beer should develop a reasonable volume of head of creamy appearance and have the stability to hold before breaking down. When the beer is consumed some of the head should adhere to the side of the glass.
It should have a distinct, fresh and pleasant aroma and since it is mainly derived from malt and hops, should have a hop character and a slightly malty flavour.
The taste should be full, clean to the palate and possessing life from the carbon dioxide gas (COâ‚‚) content. The beer should be free of any harshness or unpleasant after taste.
The key to successful flow from keg to glass is COâ‚‚. This inert, colourless and odourless gas is formed naturally during the fermentation stage of brewing and is a vital constituent of beer.
During storage, filtration and cask filling, every care is taken in the brewery to see that COâ‚‚ escapes from the beer. This is done by keeping the beer at low temperatures, by keeping it constantly under pressure and by avoiding agitation.
If during the drawing and handling of a keg any considerable portion of the COâ‚‚ is lost, the character of the beer will be altered and it will pull into the glass without life and appropriate bead, resulting in a dull or flat pour.