Production of biogenic amines by some Enterocaberiaceaea strains isolated form dairy products

Eighty-two strains of Enterobacteriaceae isolated from cheese were examined to evaluate their capacity to produce four biogenic amines at 37 °C in vitro. All of the strains produced at least one biogenic amine (almost all putrescine). In a second step, the formation of histamine by one strain of Klebsiella oxytoca, two strains of Citrobacter freundii, one strain of Proteus vulgaris, one strain of Hafnia alvei and two strains of Morganella morganii were evaluated at: 4 °C, 10 °C, 15 °C and 22 °C. Six strains out of seven produced more histamine at 22 °C than at 37 °C. Putrescine and cadaverine appear to be hygienic quality indicators. Histamine production should be evaluated at a minimum of two different temperatures.