Kvasný průmysl (Apr 2009)
The Behaviour of Toxic Metals in The Brewing Process.
Abstract
Treating hops with a high dose of pesticides containing Cu and Al results in a very slight increase of their content in beer (only by a few hundredths or thousandths of mg/l). The distribution of selected toxic metals (Cd, Pb, Ni, Cr, Hg, As and Se) into beer and brewing residuals (spent grain, trub and yeast) was observed in pilot plant scale conditions. Except As, of which about half passes into beer, only a negligible fraction of the other metals passed in the beer. In another pilot plant scale experiment, the corresponding toxic metals were added into the brewing water in concentrations of 0.1-0.5 mg/l and it was observed how this excess would appear throughout the entire technological process. It was found that the majority of metals was absorbed by spent grain (primarily Hg and Pb, the least in the case of As), a part of the metals was also absorbed by the yeast (primarily Ni, As, Se). The most of the added amount that passed into beer was As (about 2/3). Except for As, the content remained below the allowed limit even after such a large addition of toxic metals into the brewing water.Treating hops with a high dose of pesticides containing Cu and Al results in a very slight increase of their content in beer (only by a few hundredths or thousandths of mg/l). The distribution of selected toxic metals (Cd, Pb, Ni, Cr, Hg, As and Se) into beer and brewing residuals (spent grain, trub and yeast) was observed in pilot plant scale conditions. Except As, of which about half passes into beer, only a negligible fraction of the other metals passed in the beer. In another pilot plant scale experiment, the corresponding toxic metals were added into the brewing water in concentrations of 0.1-0.5 mg/l and it was observed how this excess would appear throughout the entire technological process. It was found that the majority of metals was absorbed by spent grain (primarily Hg and Pb, the least in the case of As), a part of the metals was also absorbed by the yeast (primarily Ni, As, Se). The most of the added amount that passed into beer was As (about 2/3). Except for As, the content remained below the allowed limit even after such a large addition of toxic metals into the brewing water.
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