This particular beer I’m sorry to say can only be traced back to the late 1800’s. Eisbock is a German beer that claims origins in the Kulmbach district (1.). The Legend (2.) states that a brewmaster had his assistant roll some barrels of Boch Beer into the basement, but instead, he left them outside overnight and the bitter cold froze the barrels and they burst. Inside was a thick syrup like mixture and this was the origins of Eisenbock (aka Ice Beer). By freezing the beer, the water could be removed and thus create a stronger beer with higher alcohol percentage (alcohol doesn’t freeze at 32F).
So this beer started off as a second runnings, meaning I had already done the primary beer without having to sparge the grain. I sparged anyway and got what I pretty much would assume to be a Saison or Farm Ale (lower than 6% normally.) It was put outside after the wort had been boiled to cool down overnight. It cooled alright, so cold that we got this:
Yup, condensation on the top froze and so did a lot of the water near the edge. This pushed the alcohol to the center along with the non freezable parts of the beer.
So we took advantage of the situation and seperated the ice from the liquor.
As you can see we used an open wire scoop and merely filtered the ice crystals out and put them in a bowl so you can see how much ice was removed. This concentrates the mixture to more sugars and flavoring and can make a low gravity, low flavor beer into something more suitable.
About 20% of the water was removed from this mixture. We then threw the liquor into a carboy and pitched the yeast.
The Legend fails to illuminate on if the beer had just been started and the yeast was recently pitched, or if the beer was completed and going into the cellar for aging purposes. A brown syrup is mentioned and the workers apparently enjoy consuming the remains of the frozen barrel so I tend to believe the fermentation had already happened and the ice removal was after the alcohol was developed.
As you can see, I removed the ice before fermentation. This should produce similair results but I’d be interested to see how the flavor profile will be different. This leads to another project of comparisons, another day.