We’ve started digging into our archives and have come across a bevy of articles and essays written by KC Bier Co. founder and managing owner Steve Holle for a variety of beer publications prior to founding KC Bier Co. We’ll start posting these here for your enjoyment. Kicking off this series is an article from Zymurgy magazine written in May 2007, “Make Better Lager Beer The Bavarian Way – Use More Yeast!” An excerpt is below; click the link at the end to read the full article.
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In March of 2006, I spent a week with three brewers touring nine breweries in Bamberg and Munich, Germany. Many of the breweries, especially in Bamberg, are small with aging equipment cobbled together over decades and crammed into centuries old buildings with less than ideal floor plans for a modern brewery. Yet, the brewery was able to produce very good beers, which I credit to the power of yeast and a fastidiously clean brewer.
Cleaning protocols often includes only a brush and elbow grease, and fermentation is sometimes conducted in open fermenters. Yet, in spite of these challenges, each brewery produces great beer. In certain ways, these Bavarian brewers are coping with the same issues as a homebrewer who pieces together a multitude of gadgets constituting a brewery in an overcrowded garage or basement. The reasons for their success are applicable to homebrewers as well.
The first key to the Bamberg brewers’ success is the short distance they distribute their beer, which is often sold on premise (like a homebrewer) or distributed within a very short radius from Bamberg. Even if some of the filling equipment introduces elevated levels of oxygen and the pipe work isn’t extremely sanitary, the beer remains delicious until drunk a few days later. The short time period between packaging and consumption does not allow for defects to be manifested. Because of the freshness, Germans still expect that beer drunk within site of the brewery smokestack will be the very best beer.
However, these breweries also use another safeguard. They ferment with lots of healthy yeast at cold temperatures. Each of the small breweries we visited obtains fresh yeast from a larger brewery nearby because they do not have the time, space, or financial capacity to propagate their own yeast. The large breweries seem unconcerned about safeguarding a proprietary yeast strain. The yeast is treated just like any other ingredient. In fact, many of the brewers did not even know the specific yeast strain they were buying.
Lager yeast works and multiplies more slowly than ale yeast because the cooler fermentation temperature slows down the yeast’s metabolic activity. This is the reason that brewers use larger quantities of pitching yeast for lagers compared to ales (typically 50 to 100% more yeast). The Bamberg breweries usually obtain their yeast in sterile milk cans immediately before brewing and then pitch directly into the brew. Their pre-pitching protocol, if any, is usually limited to mixing the yeast slurry with a slotted spoon to homogenize and aerate.
Finally, the brewers use traditional cold fermentation. Lager beer first gained popularity in medieval times because of its clean taste and stability. When Bavarian monks unknowingly selected for yeast that could ferment at cold temperatures, they reduced the number of spoilage microbes that could only survive in a warmer environment. When beer was fermented cold and stored cold, it remained stable longer before souring.
The most fascinating brewery that I visited was the brewpub Union Bräu on Max-Weber-Platz in Munich. In an attempt to replicate an old-fashioned brewery, Union Bräu operates one of the most archaic commercial brewing systems I have seen. Yet, the brewery was able to produce very good beers, which I credit to the power of yeast and a fastidiously clean brewer. Union Bräu is an excellent working museum that demonstrates how beer was made 100 years ago.
My hero, Japanese-born and German-educated brewer Yasubumi Sawamura spends 2 days brewing and 3 days cleaning each week. Yasubumi said he initially believed that he could never brew contamination-free beer when he first started working at Union Braeu. Yet, he said he has never had an off-tasting beer, which is a tribute to his hard work, since the whole brewery must be cleaned by hand. Secondly, the fact that he uses a large quantity of yeast ensures that the yeast can overwhelm and crowd out spoilage organisms.
Finally, the cold temperatures inhibit the growth of other organisms because their metabolism and growth are drastically reduced by the cold. In this regard, Union Bräu is a throw back to the original attraction of lager yeast – it could produce clean tasting, spoilage resistant beer without the application of modern sanitation practices. The quality beer served at Union Bräu is a testament to the historic power of lager yeast and the dedication of one highly motivated brewer.
-Stephen R. Holle, May 2007
IBD Diploma Brewer, GABF Judge, and member of the North Texas Homebrewers Association
CLICK HERE FOR FULL ARTICLE: “Make Better Beer with Better Yeast 5-19-07”
