MINIMUM REQUIREMENTS FOR ZINC AND MANGANESE IN BREWER'S WORT

Abstract

Five procedures for the extraction of metals from wort are described. Using worts with defined metal content the essential nature of zinc and manganese in fermentation has been confirmed. Despite this, zinc appeared to prevent yeast growth and fermentation when present at 0.6 ppm in a wort containing less than 0.01 ppm of manganese. This inhibition was released on addition of 0.6 ppm of manganese to the wort and it seems that the desirable concentration of any one metal ion in a wort depends to some extent on the concentration of the other related metals present.