Carlos Silva Ferreira (1), Etienne Bodart (1), Sonia Collin (1), Marie-Lucie Kankolongo Cibaka (1); (1) Université catholique de Louvain, Louvain-la-Neuve, Belgium
Renowned for a long time around the world for its unique dry-hopped Trappist beer, Belgium has also been developing other dry-hopped beers, often with a nice equilibrium between bitterness, astringency, fruity flavors and green notes. More than 25 different labels are already available on the market, most of them integrating dual hops. Addition of hops during the late stages of the brewing process (in presence or not of yeasts) brings singular characteristics to the beer. Free flavors (terpenols, polyfunctional thiols, etc.), bound adducts (glucosides, cystein- and glutathionyl-thiol adducts, etc.), polyphenols and un-isomerized bitter components of hops can significantly modify the flavor profile of such beers The aim of the present work was to investigate the main characteristics of the available dry-hopped Belgian beers. First, basic properties were determined for all the beers (apparent, real and primitive extracts, alcohol content, color, pH, bitterness, total polyphenols, total flavanoids, anthocyanogens, turbidity, sensorial analyses). GC-MS and HPLC/MS/MS were further applied to better define their sensorial profile (complete polyphenol analyses including flavan-3-ols, xanthohumol and stilbens, main bitter molecules including alpha-acids, iso-alpha-acids, humulinones and hulupones, short-chain fatty acids, esters and fusel alcohols, polyfunctional thiols and terpenols). All together, these results will help us to define the identity of Belgian dry-hopped beers.
Carlos Silva Ferreira received his engineering degree from the Federal University of Viçosa, Brazil. In 2012 he started focusing his studies toward brewery technology, which led him to an internship in Belgium in 2013 as an exchange student and intern at the Brewery and Food Industry Laboratory at the Université Catholique de Louvain. In June 2015 he came back to the same laboratory as a researcher, becoming an assistant in September 2015 and a Ph.D. student in March 2016, with a thesis project concerning dry-hopped beers.