Bottlenecks in continuous hops drying with conveyor-belt dryer

Abstract

Hops are an essential raw material in beer brewing, providing typical flavor and aroma characteristics to beer. Freshly harvested hop cones must be dried immediately. While conveyor-belt dryers are widely used, their operation is largely based on operator experience, which leads to energy-intensive operation whilst adversely affecting the quality. This work identifies the bottlenecks in hops drying by summarizing the results of previous studies, and experimentally analyzing an industrial dryer. Heterogeneous air-distribution, uneven drying and suboptimal control-strategies were identified as key issues which can be battled with accurate model-based process analysis and smart control systems, both of which need further research.