Formation of histamine and tyramine by some lactic acid bacteria in MRS-broth and modified decarboxylation agar

The ability of nine ale and nine lager brewing strains of Saccharomyces cerevisiae to produce volatile sulphur compounds during fermentation of brewers' wort was studied. In general, lager strains produced higher levels of hydrogen sulphide, methanethiol and methyl thioacetate than did ale strains. Methanethiol was shown to be a precursor of methyl thioacetate in both ale and lager strains.