Flavor-active esters: Adding fruitiness to beer

• Published in: Journal of Bioscience and Bioengineering Vol. 96; no. 2; pp. 110 - 118
• Main Authors: Verstrepen, Kevin J., Derdelinckx, Guy, Dufour, Jean-Pierre, Winderickx, Joris, Thevelein, Johan M., Pretorius, Isak S., Delvaux, Freddy R.
• Format: Book Review Journal Article
• Language: English
• Published: Amsterdarm Elsevier B.V 2003; Elsevier Science
• Subjects: alcohol acetyl transferase (AATase); aroma; ATF2; ATFI; beer; BEERS; Biological and medical sciences; ESTERS; FERMENTATION; Fermented food industries; flavor-active esters; FLAVOUR COMPOUNDS; Food industries; Fundamental and applied biological sciences. Psychology; isoamyl acetate; volatile esters; volatile esters; ATF2; ATFI; fermentation; isoamyl acetate; flavor-active esters; aroma; beer; alcohol acetyl transferase (AATase); Volatile compound; Yeast; Review; Fermentation; Flavor; Beer; Ester; Aroma
• ISSN: 1389-1723; 1347-4421
• DOI: 10.1016/S1389-1723(03)90112-5

As they are responsible for the fruity character of fermented beverages, volatile esters constitute an important group of aromatic compounds in beer. In modern high-gravity fermentations, which are performed in tall cylindroconical vessels, the beer ester balance is often sub-optimal, resulting in a clear decrease in beer quality. Despite the intensive research aimed at unravelling the precise mechanism and regulation of ester synthesis, our current knowledge remains far from complete. However, a number of factors that influence flavor-active ester production have already been described, including wort composition, wort aeration and fermentor design. A thoughtful adaptation of these parameters allows brewers to steer ester concentrations and thus to control the fruity character of their beers. This paper reviews the current knowledge of the biochemistry behind yeast ester synthesis and discusses the different factors that allow ester formation to be controlled during brewery fermentation.