The alcohol-free beer trend | After almost 30 years the Bavarian State Brewery Weihenstephan has invested in a new de-valcoholisation plant. This sets the oldest brewery in the world up for the future and enables it to perfectly cater for the growing demand for alcohol-free speciality beers. Greater productivity, flexibility and the use of cutting-edge technology were what triggered the decision to place the order.
In 1993, the Bavarian State Brewery Weihenstephan in Freising, Germany, procured one of the very first dealcoholisation plants, then developed by the Technical University Munich (TUM) in Weihenstephan. At the time the state brewery was a pioneer on the German brewing scene with its state-of-theart technology, with the plant in constant use up until the beginning of 2021. Originally designed for an hourly output of five hectolitres, ten years ago the production capacity was doubled to account for the positive development in sales of alcohol-free speciality beers. With a rate of ten hectolitres, the semi-automatic and thus extremely personnel- and work-intensive system had now reached the limits of its capacity, however.
Alcohol-free beer is very popular with consumers. In the last few years Weihenstephan has also notched up a continuous growth in this segment, making a new system essential. By moving the entire logistics setup from Weihenstephan Hill to the new logistics centre on the Clemensänger industrial estate in Freising in the middle of 2019, space was freed up in the production hall and outside for the turnkey project to be realised. The project comprises a dealcoholisation plant with a filling station that meets the latest safety, environmental and explosion protection standards. The filling station is installed in the outdoor area for customers who process ethanol for disinfectant, cosmetics or bioethanol additives for fuel (E10 petrol), for example.
Preparing the invitation to tender
Once it had been decided to give the project the go-ahead, Tobias Zollo, first master brewer at the Bavarian State Brewery Weihenstephan, drew up an extensive performance catalogue with the help of the Weihenstephan Technical Office naming the required criteria and parameters. “An investment project of this size can’t be managed alongside my daily tasks as first master brewer without expert advice. The core competencies of the Weihenstephan Technical Office provide support with invitations to tender such as this one. They helped us, from the formulation of the tender documents and selection of suitable companies to organisation of reference visits to studying and assessing the offers made and
The new dealcoholisation plant in the production hall at the Bavarian State Brewery Weihenstephan
checking the ordered performance indicators during final acceptance. From my side of things, the list of requirements was clear: the plant should be similar in principle yet have greater efficiency, yielding results that are biologically more stable with a perfect taste, and should give us enough scope to make adaptations and implement extra options in the short to medium term. When investing in a new plant, it’s essential that we retain our extremely elaborate, stable taste process. And we wanted to generally be more flexible and, first and foremost, well set up for the future. What’s more, it’s important to know and to account for what’s been achieved technically and technologically in this field over the past few years and which companies can provide this. This full overview of the market is precisely what the Weihenstephan Technical Office contributed to the project. One of the biggest challenges for the companies invited to tender was to successfully master the fine balance between efficiency and taste.” Tobias Zollo also asked for sensory expertise from the TUM, namely from expert Dr. Martina Gastl, and inquired about the latest research findings and current state of the art regarding the technology.
Vacuum falling film evaporation instead of interrupted fermentation
The alcohol-free, top- and bottom-fermented speciality beers from the Bavarian State Brewery Weihenstephan have always been made using a special process: vacuum falling film evaporation. This is an especially elaborate, but gentle, procedure, where alcohol is removed from the fully fermented and matured beer by heating it in a vacuum. This means that the beer’s taste and character are largely preserved. The alcohol-free beer also tastes less sweet and is much lower in calories than if it were produced by interrupted fermentation. With the latter method, fermentation is prematurely halted to prevent alcohol from forming. The non-alcoholic varieties of beer produced as a result are sweeter as they contain more residual sugar, which is not the case with the process favoured by the state brewery. “We held extensive tasting sessions with the TUM so that we can also continue to offer our typical flavour profile with our alcohol-free speciality beers in the future. We wanted to keep the temperatures in the dealcoholisation process as low as possible, for only then are most of the flavours that give the beer its taste preserved,” Zollo explains, outlining the brewery’s aim.
The Weihenstephan brewery showed itself to be something of a pioneer with reference to non-alcoholic beer back in 2012, when it reacted on a national scale to the restaurant trade’s increased demand for alcohol- free wheat beer from the barrel. Since then, the Bavarian State Brewery Weihenstephan has given its catering clients the option of serving non-alcoholic wheat beer straight from the keg. “Back then, launching Weihenstephan alcohol-free beer from the barrel was a challenge that we gladly rose to. The response since then has been entirely positive, for our restaurateurs are delighted with the quality and flexibility they gain from this,” says brewery director Prof. Josef Schrädler.
Awarding of the contract
The consultation process lasted a good six months, with three to four of these spent preparing the tender documents. Besides corosys Beverage Technology GmbH & Co. KG in Hofheim am Taunus, Germany, two other well-known companies were also asked to submit an offer. This was followed by reference visits to breweries where the companies had successfully managed similar tasks. corosys was awarded the contract in the summer of 2020. Prior to acquiring this order, corosys had successfully implemented two other projects at the Bavarian State Brewery Weihenstephan: the installation of a water deaeration system in 2012/2013 and of an ethanol meter in 2020. “We demonstrated that we could individually cater for the requirements of the Bavarian State Brewery Weihenstephan and successfully fulfil the order on both a digital level and as regards the level of automation. The state brewery’s own experience and their positive reference visit certainly also played a key role in them again deciding to work with us,” says corosys sales engineer Stefan Meyering confidently. He was the man responsible for the project on Weihenstephan Hill together with his colleagues Hans-Uwe Fischer, programmer, and Jan Oertli, chief project manager. “We wanted to design the new plant for the future and know that we’d included options that we could quickly and easily retrofit should the need arise. Everything was to be prepared so that, for example, the product range could be extended in the nonalcoholic segment if required,” Tobias Zollo explains.
Challenges during project planning and commissioning
Manufacturing the parts for the plant took a good four months before the new system was then installed and wired directly into the Weihenstephan production setup. A further four weeks were scheduled for commissioning. There were a number of complex tasks to solve. For instance, the room in the production wing where the plant was to be installed is of limited height. In addition, installation and commissioning of course had to take place during ongoing production. Zollo also found it important that two cooling circuits were installed and that carbonisation and mother beer dosing could be integrated using Anton Paar measurement technology. To date, these units were connected through the brewery’s own operator cabinet that was no longer to be used as such in the future but was to instead serve
1st master brewer Tobias Zollo checks the vacuum process at the sampling port
as an interface between the new dealcoholisation plant and the Anton Paar measuring equipment. “Nobody had ever done this before. We built this into the operating software and programmed a suitable interface so that the measuring devices could be quickly implemented,” Meyering states, and goes on to talk about the commissioning process. “Despite ongoing operation, installation went smoothly. We defined the various interfaces in advance and devised suitable solutions. We installed the system ourselves, including the wiring, and had all the help we needed from the brewery. The first beer was produced on the plant at the end of January. All we then had to do was tweak a few points here and there and make a couple of minor adjustments.” Jan Oertli and Hans-Uwe Fischer from corosys were chiefly responsible for the individual solutions implemented at Weihenstephan; they explored all kinds of avenues for the control technology to best satisfy the brewery’s requirements. The full package also included training and practical instruction on the apparatus for the employees who are to work on it in the future. corosys also has remote access to the plant around the clock. “If required, we can access the machinery through a remote connection and analyse and optimise it based on the recorded data,” Meyering says, describing another of the service modules. “The system is clever enough to extract and store all of the relevant and important data.”
At the ethanol filling station outside the building alcohol, caustic and CO2 can be filled up in line with the latest safety standards
The full package also included training and practical instruction on the apparatus for the employees who are to work on it in the future. corosys also has remote access to the plant around the clock. “If required, we can access the machinery through a remote connection and analyse and optimise it based on the recorded data,” Meyering says, describing another of the service modules. “The system is clever enough to extract and store all of the relevant and important data.” line with the latest safety standards
First interim project results
Zollo made an initial assessment after the first few weeks of operation. “All in all, the new plant eases the load in many respects. We don’t have any more manual work steps and can control the entire process from a single operator panel. This makes the work processes less susceptible to error and at the same time shifts are easier to plan. The production process has also been optimised in the course of the project, with a consistently stable quality the result. We’ve achieved our primary aim of doubling capacity and with an hourly output of 20 hectolitres we’re well prepared for the future. Throughout the entire project corosys always reacted flexibly to our requests and catered for our specific brewery requirements. The software thus isn’t an off-the-peg solution but one specially customised for us, as we don’t use a standard steam process but instead work with high-pressure hot water.” The turnkey project – from the dealcoholisation plant to the ethanol meter and underground collection tank to the ethanol filling station, where caustic and CO2 can also be extracted – is a holistic process that is state of the technical and technological art and adheres to current safety and environmental standards. It will undoubtedly help the trend for more alcohol-free speciality beers to flourish – at least where the Bavarian State Brewery is concerned.