Mass - produced versions of krupnik consist of 40 -- 50 % ( 80 -- 100 proof ) alcohol .
Traditional versions will use 80 -- 100 % grain alcohol as the base .
Mass - produced versions of krupnik consist of 40 -- 50 % ( 80 -- 100 proof ) alcohol , but traditional versions will use 80 -- 100 % grain alcohol as the base .