Beer of the Week: Potato Vacation Beer
Horst Dornbush, Brewers Publications author, presents this potato-beer recipe in the article "Can You Say Kartoffelferienbier" on page 41 of the January/February 2004 issue of Zymurgy magazine. Named after a traditional, week-long break from school and work for potato harvesting in Germany, Potato Vacation Beer, or Kartoffelferienbier, is a funky ale that lives outside the realm of classic styles. For a deeper look at this recipe and the use of potatoes in brewing, AHA members can head over to the eZymurgy online archive for instant access to this Zymurgy issue and many more!
Ingredients for 5 US gallon (19 L)
3.25 lb (1.5 kg) | Pale two-row Pils or ale malt (2-4° L)
2.5 lb (1.13 kg) | Munich malt (approx. 10° L)
6.5 lb (3 kg) | Peeled raw potatoes at room temperature
1.33 oz (37 g) | Bittering hops of 5% AA (Tettnanger, Fuggles, East Kent Goldings or Galena)
0.5 oz (14 g) | Aroma hops (Tettnanger, Fuggles, East Kent Goldings or Willamette)
1 tsp (5 ml) | Irish moss
1 pckg | Wyeast 1028 London, White Labs WLP005 British, Wyeast 1007 German Ale, White Labs WLP036 Alt, Wyeast 2042 Danish, or WLP830 German Lager)
1 cup (237 ml) DME or corn sugar (for bottling)
Boil time: 60 minutes
Target SG: 1.048
Target FG: No more than 1.010 (will depend on yeast)
Primary: 5 days
Secondary: 14 days
Bottle Prime: 7-10 days
Using a blender or ricer, macerate the peeled, raw potatoes. Then make a quick, thick grain mash at temperature of about 156°F (69°C). Use the least amount of water possible, but avoid lumps and dry spots. Then pour the potato mash into the grain bed and mix the grain and potatoes evenly for maximum exposure of both to all starches in the mash. Finally, top the grain/potato bed with about an inch of water at about 172°F (78°C).
All starch conversion should be completed within about 20 minutes from mixing the grain with the potato mush. At this point, you can start recirculating the wort for 15-20 minutes. Sparge the wort into a brew kettle, and stop sparging when the kettle gravity is about 1.044. Allowing for 10% evaporation, this pre-boil gravity should get your brew up to the target OG of 1.048.
Add bittering hops 15 minutes into boil. Add aroma hops 10 minutes before the end of the boil.
Follow fermentation schedule above. Prime in bottles.
Replace Pale two-row malt and Munich malt with 3 lbs (1.36 kg) plain light Pils or ale malt extract and 2.0 lbs (0.97 kg) Bavarian Munich malt extract. Because extract brewers need to convert potato starches without mashing (and there is no potato extract on the market), they need an additional 2 lbs (0.97 kg) Pale ale or Pils malt as grains for steeping with the potatoes.
Mix the pale malt with the macerated potatoes and about 2 gallons of colder water in a pot. Once the potatoes and grains are evenly mixed, heat the entire "mess" very slowly while stirring frequently to ensure an even heat distribution in the pot until the temperature has reached a target range of about 150-155°F (65 - 68°C). Then let the pot rest for another half hour, during which you want to maintain the temperature within the target range. Once complete, line a kitchen colander with cheesecloth, place the colander in a large bowl or your kettle, and pour or ladle the pot's content into the colander. Allow the mixture to drain thoroughly, which may take 15-20 minutes (shake vigorously every few minutes).
Mix the liquid you collected from the potato and grain "mess" with the 3 lbs of pale malt extract and the 2 lbs of Munich malt extract. Top off your kettle to your pre-boil volume and follow the boil/post-boil schedule as listed for the all-grain recipe.