MBAA TQ http://dx.doi.org/10.1094/TQ-54-4-1122-01 | VIEW ARTICLE
Alyce Hartvigsen. Alfa Laval Copenhagen A/S, Soborg, Denmark.
A “revolution” in the craft brewing industry has led to high demand for dry-hopped beers and increasing production in breweries both small and large. However, there are many challenges associated with the automation and scale-up of dry-hopping techniques to larger beer volumes. These include efficient introduction of the hops without excessive oxygen pick-up, effective extraction of the aroma compounds into large beer volumes, removal of the hops while minimizing product loss, and efficient cleaning in place of the system. Most existing dry-hopping systems in the market exhibit capacity limitations, are difficult to clean by automated clean-in-place processes, and are challenging to integrate into automated modern breweries. The potential of rotary jet mixers for dry-hopping applications has been considered, but the high particulate loads in the fluid require a special mixer design. Alfa Laval has developed the Iso-Mix external drive system, a new type of rotary jet mixer suitable for dry hopping of larger beer volumes. The system homogenizes hop distribution in the beer, potentially reducing the required quantity of hops while attaining the desired flavors. Homogenization continues during transfer to downstream centrifugation, improving the separation efficiency and product clarity. It is easily automated and allows flexibility in the method of hops introduction. The process configuration is similar to conventional rotary jet mixing systems, and as such, the system can also be used to optimize the fermentation, maturation, and crash-cooling processes. This article examines the challenges of large-scale dry hopping and demonstrates how the new system improves the dry-hopping process for larger tanks.
Keywords: Dry hopping, Mixing, Homogenization, Extraction, Separation, Extract loss