 The beer was variously produced using an infusion mash or a decoction mash . <unk> records from the Grodzisk brewery documented an infusion mash that included a 30 @-@ minute acid rest at 38 ° C ( 100 ° F ) , a 30 to 60 minute protease rest at 52 ° C ( 126 ° F ) , an α @-@ amylase rest for 30 minutes at 70 ° C ( 158 ° F ) , and a mash out at 75 ° C ( 167 ° F ) . The wort was boiled for 90 to 120 minutes . Approximately 80 % of the hops were added after 15 minutes and the remaining 20 % were added 30 minutes before the end of the boil . 
