Copper may be transferred to beer from pesticide residues as well as through contact with brewing equipment and piping. Heavy metal ions have a negative effect on the colloidal stability as well as the flavor of the beer.
Determination of copper content in beer
This method is also suitable for dark and turbid beers. The turbidity particles must be evenly distributed before sampling.
This method is based on the formation of a yellowish-brown, (insoluble in aqueous medium) copper (II) chelate with zinc benzyl dithiocarbamate (ZDBT), a compound that may be extracted with trichloroethane.