Fermentation of wort is the most critical step of beer production. Fermentation difficulties may be caused by inadequate wort composition, i.e. insufficient supply of trace elements. Wort provides trace elements for yeast. Among them zinc, which is essential for beer fermentation, is not available in the required amount in wort. Zinc utilization in fermentation was studied in beers made with adjunct (maize, barley). Inductively coupled plasma-atomic emission spectrometry was used as analytical method for the determination of zinc concentration. Addition of zinc made the fermentation faster. The best result was achieved at 0.4 mg l-1. Synthesis of aroma compounds was also promoted at this concentration. Concentrations higher than 0.4 mg l-1 did not affect significantly either the fermentation rate or the maximal ethanol concentration. Addition of zinc at the end of wort boiling did not prove to be practical, it is better to supply yeast with zinc.
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