Brewing Vienna Lagers
Vienna lagers are relatively malty beers with a dry finish. Let's look at how the water character in Vienna makes that possible.
The surprising thing about the water supply in Vienna, is its seemingly high sulfate level. With about 60 ppm sulfate and 15 ppm chloride, it seems counter-intuitive that the brewers there could make a seemingly malty beer there. But that is the anachronism that is sulfate. It does not prevent you from making a malty beer. In some ways, having an adequate sulfate level helps a brewer create a malty beer that is still drinkable since that beer is more likely to have a more drying finish. In fact, Burton on Trent brewers were known for their Burton Ales, which were very malty, high gravity beers. Not the hop-focused beers that most correlate with Burton. They did use the sulfate-rich Burton waters and they did produce malty beers that were treasured...probably because they finished cleanly due to the sulfate content.
When you review the description of what a Vienna lager should taste like, an important thing should jump out. "Fairly dry finish" is right there in the flavor description and essentially parroted in the mouthfeel description. For that reason, you are likely to find that employing that elevated sulfate content that comes straight out of the Danube River, is an appropriate consideration. I suggest that the boiled Vienna profile is an appropriate guide for your water additions. Do recognize that the Danube water is fairly alkaline that far down river and even after boiling or lime softening, it would still have that modest alkalinity that will require some form of lactic acid addition to neutralize. Many breweries in Germany faced with alkaline water, employ a continuously-operating sauergut fermenter to supply them with Reinheitsgebot compliant soured wort that is added to the water.
As with any fine lager, keeping the calcium content low, is an important factor for improving yeast performance. The roughly 30 ppm Ca content of the boiled Vienna profile is appropriate, although it can be good to have 40+ ppm in the mash to help with oxalate removal.
