Beer Carbonation(selected excerpts)
The next major process that takes place after filtration and prior to packaging is carbonation. Carbon dioxide not only contributes to perceived "fullness" or "body" and enhances foaming potential it also acts as a flavor enhancer and plays an important role in extending the shelf life of the product.
The level of dissolved carbon dioxide in beer following primary fermentation varies as a result of a number of parameters such as temperature, pressure, yeast, type of fermentation vessel, and initial wort clarity. Typically, carbon dioxide levels range from 1.2 to 1.7 volumes of carbon dioxide per volume of beer (v/v) for non-pressurized fermentations. Consequently, carbon dioxide levels need adjustment, unless the beer has undergone secondary fermentation. Common practice is to raise the carbon dioxide level between 2.2 and 2.8 v/v and possibly more prior for bottled and canned products. The carbon dioxide levels for kegged beer typically range from 1.5 to 2.5 volumes (2).
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