Petrus Sour Blackberry Ale is a blend of the famous Petrus Aged Pale sour (a 100% Foeder beer that is aged 24 months in Calvados Oak Foeders) and Blackberries. Without overpowering fruit flavor or sweetness, fresh Blackberry subtly melds with the Mother Beer creating a unique, complimentary, one of a kind sour ale! Limited quantities available.