Bottle: Unfiltered. Aged In Oak Foeders Flanders Red Ale (Also sold as Belgian Sour Ale) Natural, unfiltered, unfined and vegan friendly beer. A blend of 1/3 young beer and 2/3 of beer aged 2 years in large oak vats. The more important proportion of oak matured beer contributes to its fruity taste, complexity and intensity. The finish is worthy of a great wine.