Andreas Krennmair is an Austrian-born homebrewer and amateur beer historian who lives in Berlin. In 2018, he self-published Historic German and Austrian Beers for the Home Brewer, which dug deeper into German-language sources and brewing logs than most other English-language texts had done before. This year, he follows up with a book that digs deeper on a style more associated with his native country: Vienna Lager.
A disclosure: Andreas and I were in the same beer-geeky stammtisch in Berlin, we are friends, and he asked me to write a foreword for the book. He also knows more about Vienna lager—especially its history, methods, and composition—than anyone else I know.
So, I had questions.
CBB // What would you say are the main differences between late 19th-century Vienna lager and the Vienna lager we might find at a typical craft brewery today?
AK // Nineteenth-century Vienna lager followed a very classic scheme of lager-brewing of the period: a single type of malt, kilned to the right specifications; triple-decoction mashing, how it was originally practiced in Bavaria, then refined by Viennese brewers; quality hops; fermentation at low temperatures, with a yeast that produced a fairly sweet and full-bodied beer; and long lagering periods of several months.
I think the Vienna lager that craft breweries brew nowadays can be put into two categories. Those developed at a time when Vienna malt was hard to get or not of the right quality—in the 1980s and 1990s—often try to imitate the typical character with specialty malts, such as dark caramel malts. More recent beers seem to go back to the classically kilned malts, often accentuated with only moderate amounts of specialty malts, if any at all.
Both categories have in common that they typically use infusion mashing, either single-step or multistep, and, of course, brewers nowadays have much better-attenuating lager yeasts that produce drier beer at a quicker turnaround. Some craft breweries still choose to use typical Continental hop varieties, while others put their spin on Vienna lager by brewing it with more fruity New World hops.
CBB // How close is today’s widely available Vienna malt to what Anton Dreher and his contemporaries were malting, based on the information available?
AK // Ultimately, this is hard to determine. The state-of-the-art kilns in the late 19th and early 20th centuries were two-floor, hot-air kilns. Up to the 1880s, some of these kilns had issues with extracting hot air well enough—and most importantly, extracting moisture quickly enough. Increased humidity promotes the formation of melanoidin at higher kilning temperatures.
The same historic sources that talk about these issues also describe the final kilning (or curing) at temperatures lower (167–189°F/75–87°C) than what modern Vienna malt would be cured at (194–203°F/90–95°C). On the other hand, we have reports from Anton Dreher’s second brewery in Hungary that the malt was dried with final temperatures from 176–200°F (80–93°C). Not all malt was cured at the same temperature. For the regular lager beer, it was cured at a lower temperature (176°F/80°C); for the märzen at 185°F (85°C), while for stronger beer, the temperature was as high as 196–200°F (91–93°C).
When we look at the color of beers from around the same time period, Vienna lager seems to have been slightly paler than what we’d expect from Vienna lager nowadays—roughly between 4 to 6 SRM (about 8 to 12 EBC)—which was still a bit darker than pale Bohemian lagers at the time, which were typically between 2.7 and 3.7 SRM. Very generally speaking, Vienna malt has been described as being “in between” the very pale Bohemian (pilsner) malt and the darker Bavarian (Munich) malt. The same goes for Vienna lager being slightly bitter and malt-aromatic, as opposed to the highly hopped, very pale, and dry Bohemian lagers and the much maltier, sweeter, and less bitter Bavarian dark lagers.
The raw materials have, of course, changed in the past 150 years. Maltings use different barley varieties than back in the day, and, of course, malting technology has been improved and rationalized as well. So I would say that while there probably is some difference, the general character of the malt has still been preserved, and even old descriptions of the look, aroma, and flavor of Vienna malt and Vienna lager still seem to match the modern product.
CBB // From a hedonistic perspective, what do you look for in a really great one?
AK // The ideal Vienna lager for me would be a beer that I could drink all evening—a true session beer. It doesn’t need to have a lot of alcohol, but it should be full-bodied and have enough malt character that can stand on its own and should also be balanced out with a firm bitterness. I prefer it more bitter than how most examples are brewed.