Development project themed around dynamic fermentation

Brewers have very stringent requirements for their kit: shorter fermentation and storage times, upsized cellarage capacities, improved cooling rates, and at the same time enhanced efficiency of sediment removal – and all this is precisely what’s being addressed by an ongoing development project at Krones AG.

It’s already well enough known that recirculated processes are able to speed up fermentation. But whereas hitherto it was always the entire tank contents that were homogenised, an earlier research project conducted by the TUM University in Weihenstephan has already shown that it’s more advisable to selectively recirculate particular zones only. Given an appropriately controlled process, this enables particles to be deposited (at the end of fermentation, for example) while the liquid in the upper part of the tanks is being blended at the same time.

On the basis of these findings, Krones has developed a pipe-in-pipe system inserted from below, enabling selectively determined sections in the tank to be blended. In order to remove the sediment more efficiently, and prevent channel formation phenomena, a hygiene-compliant displacer element was additionally connected to the pipe-in-pipe system.

The unit and the process involved possess numerous advantages: for instance the design can be quickly and easily retrofitted inside existing tanks. A huge range of different flow profiles can be flexibly selected, and matched to the processes concerned. There’s also an option for interconnecting the systems in such a way that besides the classical batch production mode continuous fermentation processes can also be run – during the peak season, for instance. The design’s advantages also include: there are no moving parts located in the liquid, cleaning can be ideally assured, and mash fermentation operations, i.e. fermenting fluids with a solids content, can likewise be implemented.

Initial long-term trials on a larger scale are currently being run in order to empirically validate these findings.


Krones mounted the pipe-in-pipe solution on a skid, which is simply connected up to the tank cone in plug-and-play mode.