Influence of (+)-catechin and ferulic acid on formation of beer haze and their removal through different polyvinylpolypyrollidone-types

The influence of (+)-catechin and ferulic acid on the formation of haze was investigated. Both phenolic compounds were added in different concentratio ns to beer before ageing through a force test. The removal of these compoun ds was observed by measuring the difference before and after forcing the be er. (+)-Catechin and ferulic acid showed haze-decreasing as well as haze-in creasing properties. The removal of (+)-catechin and ferulic acid from beer through three types of polyvinylpolypyrollidone (PVPP) at several concentr ations was investigated. The removal of (+)-catechin and ferulic acid by PV PP-filtration was totally different. The removal of (+)-catechin can be use d as a basis to calculate the doses for a desired stability, whereas feruli c acid is removed in irregular amounts.