Thomas Kunz (1), Anna Meshcheriakova (1); (1) Technische Universität Berlin, Chair of Brewing Science, Berlin, Germany
Finishing and Stability
Fining agents are used to improve the filtration performance and to reduce the production time of clear and bright beers. Based on earlier studies the aim of this investigation was to compare the influences of different pectin and gallotannin/pectin applications during the maturation process as possible non-allergenic, plant-derived fining agents in the brewing process. In these investigations fining agent concentration, dosage sequence, temperature, etc. were of particular importance in handling. The applied pectin or gallotannin solutions in defined concentrations and combinations directly cause a precipitation by adsorption and chemical bonding with haze particles and haze-active protein fractions. In contrast to the reference without fining agents the generated pectin or gallotannin/pectin floc can be removed from the tank cone after 3-4 days of maturation prior filtration. Consequently, the unfiltered beer shows much better brightness compared to the reference, resulting in significantly better filtration performance after a shortened maturation time. Furthermore, the final beers demonstrate a minimum comparable or improved oxidative and colloidal stability. The correct application of pectin or better yet a specific gallotannin/pectin combination seems to be an efficient tool to reduce the maturation time and improve the filtration performance accompanied by reducing the amount of filter aids like kieselguhr or stabilizing agents.
After qualifying as a certified technician in preservation engineering (1991-1993), Thomas Kunz completed his basic studies in chemistry at the University of Applied Sciences, Isny (1994-1995) and his basic studies in food chemistry at Wuppertal University (1995-1998), before starting to study food technology at the University of Applied Sciences, Trier (1998-2002). After graduating, he worked as a chartered engineer in the area of ESR spectroscopy at the Institute of Bio Physics at Saarland University (2002-2004). Since 2005 he has been employed as a scientific assistant, Ph.D. student and since 2009 as head of the laboratory at the Institute of Food Technology and Food Chemistry, Chair of Brewing Science, Technische Universität Berlin. His main research focus lies in analyzing radical reaction mechanisms and oxidative processes in beer and other beverages using ESR spectroscopy. A further research focus consists of the optimization of filtration and stabilization processes.