October 2022

We brewed another new Pilsner beer on the last day of October, and apart from minor adjustments to the malt mix, the batch itself was identical to the one from 24.09.2022.
We brewed again with a batch (44 kg) consisting of Pilsner malt, Pale Ale malt and Carapils, and a total of 200 liters of wort with 11.5 °P was achieved. This time we changed the brewing parameters a little. Mashing was carried out at 78 °C, and after 30 minutes at 74 °C, lautering was carried out at 74 °C, with the final sparging using water at 78 °C.
Even under these conditions, residual saccharification took place reliably during lautering, and the wort was iodine-normal after a further 45 minutes. The wort was boiled with the bittering hop "Enigma", for the aroma we used Wethop Blanc in the whirlpool at around 80 °C, a rather unusual hop for Pilsner beers, which imparts mild fruity aromas to the beer.
The brew is fermented with Lallemand "Diamond Lager", a well sedimenting and neutral fermenting Pilsner yeast. We are curious to see how these slightly higher temperatures for mashing and lautering will affect the alcohol content and drinkability.

The year is slowly coming to an end, the days are getting shorter and the first snow could fall in the Oberharz in the next few weeks. Well, and Christmas is just around the corner. From our point of view, this is the perfect time to brew our mild smoked beer.
Bamberg is certainly known as the city of smoked beer, and there is a saying in brewing circles that you have to drink three glasses of smoked beer in Bamberg for the fourth to taste good. To ensure that our smoked beer tastes good from the very first glass, it is brewed with a maximum of 40% smoked malt. In the Braumeister 50, we therefore mashed a batch of 7 kg Munich malt and 4 kg beech smoked malt isothermally at 72 °C for 30 minutes. We routinely lauter at 72 °C instead of the usual 78 °C. The system keeps the temperature of the wort in the malt pipes constant at 72 °C so that any starch that has not yet been broken down can be reliably saccharified in the wort.
After a total of 60 minutes, mashing and lautering were complete, resulting in 50 liters of wort with 12.3 °P. Bitter hopping was carried out with 20 g of the high-alpha hop Enigma (18.2 % alpha), wort souring was also carried out with Döhler Sauergut, aroma hopping was not carried out. Our previous results indicate that mash acidification during isothermal mashing at 72 °C weakens the activity of alpha-amylase, so we switched to wort acidification. Further results indicate that lautering is faster when there is no mash acidification, which may be related to the precipitation of proteins at lower pH in the mash.
Today we needed exactly 2 hours and 50 minutes from mashing in to striking out, one of the fastest brews so far. We chose a non-pressurized, thermostated fermentation, the brew is fermented at a constant 13 °C with fresh bottom-fermenting yeast (Lallemand Diamond Lager) taken from the gusset tap of one of our cylindrically-conical fermenters. Fresh yeast from a recently completed fermentation is very active and accustomed to beer wort, especially as there are predominantly live yeast cells in suspension. As a result, fermentation usually starts quickly.
This mild smoked beer should be ready to drink by the middle/end of November. It goes very well with cheese fondue or other rather hearty dishes. However, we wouldn't necessarily use it for our mulled beer.

At the end of the current student internship, we brewed two Kveik beers and a (planned) non-alcoholic wheat beer on October 1 and 2. The name Kveik stands for yeasts that occur in Norway and are traditionally used there. The yeasts are often named after the place from which they originate, and so, for example, the "Hornindal Kveik" comes from the small town of Hornindal, which is roughly halfway between Bergen and Trondheim.
These yeasts are ultimately to be regarded as top-fermenting yeasts, although they can be genetically distinguished from the classic top-fermenting yeasts. What all these yeasts have in common is that they ferment very quickly, sometimes at temperatures of up to 40 °C (!). If such a high fermentation temperature were to be attempted with a bottom-fermenting Pilsner yeast, a typical Pilsner taste could hardly be expected, and many Pilsner yeasts do not even survive such temperatures. A classic wheat beer yeast would also tend to produce an increased amount of so-called fusel oils at such high temperatures, and the risk of a "headache beer" should not be underestimated. The Kveik yeasts have different optimum fermentation temperatures and it is advisable to follow the temperature recommendations of the yeast manufacturers.
Every brewer knows that "the brewer makes the wort, the yeast makes the beer", and so this time we produced a total of 100 liters of wort in our Brewtools 150 Pro with Pale Ale malt and Carapils using the isothermal (72 °C) mashing process and a simple bitter hopping, which was divided between two cylindrically-conical fermentation vessels (ZKG). The wort was poured in so that an initial temperature of 33 °C was reached. The two wort were fermented once with the Imperial Yeast "Kveiking". This is a blend of 3 Kveik strains and, according to the manufacturer, produces aromas of pineapple, guava and other tropical fruits at these temperatures. Together with the original gravity of 13 °P, this should result in a beer with "high drinkability".
In the other fermentation vessel, the wort is fermented with the "Opshaug Kveik" from Whitelabs. According to the manufacturer, this yeast historically comes from the farmer Harald Opshaug in Stranda, Norway, and is said to be characterized by a very neutral fermentation. Accordingly, both beers should later differ significantly in taste, although the wort was identical.
It is also noteworthy that the Kveiking took just 16 hours to fully ferment the wort at 33 °C, while the Opshaug Kveik took a little longer and still needed a quick 48 hours for complete fermentation. Not even wheat beer yeasts can keep up with that. The two young beers are already under pressure, and in the next few days the temperature will be lowered to 3 °C for maturation.
 

The production of non-alcoholic (< 0.5% by volume) beers is now a standard procedure in large breweries with decarbonization plants, and compared to the beginnings more than 40 years ago, today's non-alcoholic beers are very drinkable. The catch, however, is that such dealcoholization plants would more than exceed the budget of a university research brewery or microbreweries, not to mention the space requirements and minimal throughput. For the production of non-alcoholic beers, we therefore use so-called maltose-negative yeasts, which we obtain from our colleagues in Munich.
Similar to the October 9, 2021 this time we used TUM 242(Cyberlindnera amylophila), which produces aromas typical of wheat beer. As it only ferments sucrose, glucose and fructose, non-alcoholic beers with less than 0.5% alcohol by volume are achieved with original wort in the 7 °P range.
In numerous trials, we have found that the amount of glucose is slightly reduced during isothermal mashing at 72 °C compared to an infusion or high/short mashing process, while at the same time the amount of non-fermentable sugars is increased. In order to achieve the fastest possible homogeneous mashing, we used our system with agitator this time. A total of 55 liters with an original gravity of 7.3 °P was achieved, boiled in the Braumeister 50, only a mild bitter hopping was carried out.
To avoid any contamination with yeasts from a previous beer, this time we chose a pressureless fermentation under a fermentation bell. The 60 L vessel made of food-safe polyethylene was thoroughly disinfected with medical povidone iodine, rinsed several times and then sterilized with wet steam, because even just a few viable cells of a common yeast would cause them to multiply in the wort and ultimately ferment the wort completely. Instead of the planned 0.5% alcohol by volume, this would result in values of around 1.5 - 2% by volume, and the finished beer would taste somewhat watery.