Udo Funk (1), Tobias Becher (1), Konstantin Ziller (1); (1) ZIEMANN HOLVRIEKA GmbH, Ludwigsburg, Germany
Hops are the most important ingredients for establishing a specific aroma profile in beer. The knowledge of hop aroma components and their sensory result in beer are the topics of a great number of current and recent papers. In contrast the strategy and the equipment, when and how to dose this ingredient into the product to achieve certain aroma profiles, are rarely investigated. Hence, strategy and equipment often are left to the individuality of the brewers. This presentation explains the latest findings concerning reliable and flexible operation of different hop-dosing systems. Hop-dosing systems of the recent past were simple dosing vessels that were loaded with the required amount of hop pellets or hop extract. During wort boiling hop dosing took place. Hop dosing outside the brewhouse usually was only done in terms of liquid isomerized hop products dosed to finalize the product taste accurately. In large part due to the rise of craft brewers, very old and very new hop-dosing strategies have been relaunched or invented, respectively. Most of these solutions are individual developments, tailor-made and seldom replicated. More often these processes are executed manually and, therefore, are less reliable. Two hop-dosing units are described from the concept to the installation. Construction aspects, such as hygienic design and flow conditions of suspensions, are introduced. First, whole hop and specialty dosing in the brewhouse with a high level of flexibility for flavoring the wort. Integrated in a fully automated brewhouse dosing takes place during transfers as well as during batch cycles. Second, a hop slurry system from dosing of hop pellets is described. Again, the integration in a fully automated brewery cellar is developed to establish reliable dosing results. In addition, spent hop removal strategies are discussed. Construction aspects are discussed concerning hygienic design, automatic operation, feed and discharge, as well as flexibility in terms of variable products to be dosed. Different process strategies are shown to reach different flavor results in the later beer. In this regard, amounts of up to 6 kg of different hop products per hectoliter have been achieved. The presented process technology shows how to use hop-dosing strategies at first glance in the brewhouse as a circulation process or via transfer from one batch vessel to another. Second, a reliable and still flexible dry-hopping strategy has been established. New and relaunched aspects of hop dosing are integrated into a reliable process design for a reliable flavor result. The introduced equipment meets hygienic design requirements and allows automatic and flexible operation. Due to highly effective flow optimization the yield of hop extraction is increased.
Udo Funk graduated from the Technical University of Munich (Weihenstephan) as a brewing engineer in 1994. Since then he has worked in the brewery supply industry, with a focus on the process side, from malt handling to beer filtration. He has worked as a commissioning engineer, process engineer, and project manager in Europe, Latin America, and North America. In 2007 he moved to the United States and now represents Ziemann Holvrieka as sales director for North America.