Production of biogenic amines by lactic acid bacteria and bifidobacteria isolated from dairy products and beer

The aim was to monitor production of eight biogenic amines (BAs) (histamine, tyramine (TYR), tryptamine, putrescine, cadaverine (CAD), phenylethylamine, spermine and spermidine) by selected 81 lactic acid bacteria (LAB) strains: Lactobacillus, Lactococcus, Leuconostoc, Enterococcus, Pediococcus, Tetragenococcus and Bifidobacterium. The tested LAB and bifidobacteria were isolated from dairy products and beer. The decarboxylase activity of the micro-organisms was studied in growth medium after cultivation. The activity was monitored by HPLC after the pre-column derivatisation with dansylchloride. Fifty LAB showed decarboxylase activity. Thirty-one strains produced low concentrations of CAD (=10 mg L-1). Almost 70% of beer isolates generated higher amounts of TYR (=3000 mg L-1). Most of the tested LAB demonstrated decarboxylase activity. The above micro-organisms can contribute to the increase of content of BAs in dairy products or beer and thereby threaten food safety and health of consumers. Production of BAs even by the representatives of some probiotic strains (Bifidobacterium and Lactobacillus rhamnosus) was detected in this research. This study has also proved that contaminating LAB can act as sources of higher amounts of CAD and TYR in beer.