Alcohols and Esters. During fermentation a large number of alcohols, in addition
to ethanol, are formed that affect beer flavor. These are produced from wort carbohydrates via oxo-acids or from transamination and deamination of amino acids in wort. They include both
the aromatic alcohol 2-phenylethanol as well as such aliphatic alcohols as butanol, propanol,
and hexanol. The most important group of beer volatiles providing strong fruity flavors are
esters.