The three beers were an experiment in steinbier, a historic method of production. Before metal kettles, beer was made in wooden vessels. For obvious reasons, the wood could not be heated directly. To overcome this, rocks were heated in a fire and placed into the wooden vessels to raise the temperature and ultimately boil the wort. Upon contact, the stones would scorch sugars within the liquid and cause them to caramelize and cling to the stones. Some brewers then sought to return those scorched sugars to the beer by allowing the stones to soak in the beer while conditioning. Both the initial caramelization by the hot stones and the dissolution of the sugars back into the beer later were thought to impart distinct flavors of caramel and smoke.
To test this, we created three beers. The three samples of Vienna lager were identical in composition. However, Sample A was boiled conventionally using propane. Sample B was boiled by heating stones in a beechwood fire and immersing them in the kettle. Sample C was also boiled using heated stones but was later conditioned on those stones as well.
After compiling our results from the tasting we have arrived at the following conclusions. Sample A was overall the least favored. Sample B landed right in the middle, and Sample C was most highly favored. Participants consistently noted hints of banana and a higher degree of sweetness in Sample A. Sample B, while still noted as having hints of banana, was perceived as being more mild and having less body. Sample C was described as the most complex, having a unique sharpness, and appearing more cloudy.
In conclusion, there certainly appears to be some distinct characteristics that develop as a result of steinbier production methods. Notably, increased complexity and sharpness as well as a haze from the stones in conditioning. However, no smokiness was perceived and very little added caramelization.
We thoroughly enjoyed creating this ancient style of beer and bringing it to the public in the form of a blind tasting event. We are currently in the process of brainstorming new ideas for similar events and will keep you all posted when we are ready for another. Thank you to all who attended and provided us with your thoughts, opinions, and enthusiasm. Cheers!