Wood Aging of Beer. Part I: Influence on Beer Flavor and Monophenol Concentrations

Abstract

Wood aging is an old tradition that is still used to improve the sensory quality of wines, spirits, and some Belgian specialty beers. Today, it is gaining interest from brewers looking for new, innovative products. However, little is known about the actual influence of wood aging on beer flavor and composition. To elucidate the effect of wood aging on the flavor profile, a variety of oak chips was added to a commercially available beer, and the influence on the beer flavor and monophenol concentrations was determined. Sensory analysis showed spectacular effects of wood aging on the flavor profile of the studied beer, with clear increases in woody, vanilla-like, spicy, and smoky flavor notes. Furthermore, nine monophenols (vanillin, acetovanillone, syringaldehyde, acetosyringone, guaiacol, 4-ethylguaiacol, eugenol, thymol, and salicylaldehyde) showed elevated concentrations following the addition of oak chips to beer. Both sensory effects and monophenol concentrations were associated with origin and toasting degree of the oak chips used.