GEA’s reverse osmosis dealcoholization technology preserves the original character of the Andechs wheat beer.
Exactly 23 years after the Andechs Monastery Brewery launched its pale wheat beer and just in time for St Joseph’s Day (19 March), the Benedictine monks of St Boniface in Munich and Andechs, who own the brewery, premiered a non-alcoholic version. Impressing with a full and smooth body, reminiscent of the original beer, the whole process was made possible by GEA’s reverse osmosis cold dealcoholization plant.
"Our tradition is to be progressive,” said Alexander Reiss, Production Manager, “and a non-alcoholic beer had to be a sustainable product that complements and completes the whole product range. We wanted an unfiltered non-alcoholic beer with an exquisite yeastiness and the same flavor quality and elegant aroma as our pale wheat beer.”
Using a yeast-friendly, time-consuming two-tank fermentation method, interrupting the fermentation was not an option; so, to achieve the desired flavor profile, dealcoholizing the 5.5% of wheat beer was the only way to go. And, given that all Andechs beers are brewed and bottled on-site in the “Sacred Mountain,” outsourcing was quickly ruled out. Likewise, traditional evaporation technologies with direct heating or vapor-compression were felt to be inappropriate in terms of scale and risk of compromising the flavor of the beer.
The GEA Solution
Working at filtration temperatures lower than 10 °C, reverse osmosis is a gentle membrane-based dealcoholization technology that preserves the sensory characteristics — flavor, color, and turbidity — of the beer. GEA had recently developed new composite membranes that offer high chemical resistance but retain the ingredients responsible for the beer’s taste and provide a reasonable throughput.
The modular, frame-mounted Andechs dealcoholization plant comprises filtration units, media transfer pumps, piping, safety devices, a clean-in-place (CIP) dosing apparatus and the control equipment required for semi-automatic operation. Flexible by design, it can easily be adapted to the alcohol content of the beer, the desired dealcoholization level and other factors.
The excellent co-operation between the brewery and the GEA team proved to be extremely fruitful during this exciting phase.” - Alexander Reiss, Production Manager – Andechs
Following commissioning and a six-week test phase, a variety of test beers were compared and assessed for color, turbidity, odor, taste, and tanginess. Alexander Reiss notes: “The excellent co-operation between the brewery and the GEA team proved to be extremely fruitful during this exciting phase. And the results have been impressive. In fact, some of our testers actually confused the non-alcoholic version with its 5.5% counterpart!”
He continued: “There are only subtle nuances that distinguish the two beers, such as a slightly different odor and color. However, both beers have the same strong, finely textured turbidity, fine-pored head and the full, smooth body that our wheat beer is famous for.”
It’s too early at this stage to draw conclusions about the durability of the membranes, overall operating costs and how cleaning will affect the process, but membrane service lives of 1–3 years are expected. What’s already apparent, though, is the level of satisfaction at the brewery. Mr Reiss foresees no fundamental problems that would prevent reverse osmosis being used to remove the alcohol from other beers as well, especially as GEA predicts that processing filtered beer would — with the same plant configuration — offer 20–30% higher throughput rates compared with wheat beer.
The GEA reverse osmosis plant with polymer thin film membranes provides a beer dealcoholization technology that preserves ingredients, retains the sensory qualities and leaves the character of the beer almost unchanged. The plant, which is delivered on a base frame ready for installation and provides a throughput of approximately 5 hL/h is suitable for batches of 50–200 hL and offers a viable alternative to evaporation plants. Being modular by design, it can easily be adapted to meet specific requirements and accommodate larger volumes by installing multiple osmoses plants or a tailored system.