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The amino acid decarboxylating activity and production of biogenic amines by 104 cheese-associated Enterobacteriaceae species (58 Enterobacter, 18 Serratia eight Escherichia, seven Hafnia, six Arizona, four Citrobacter and three Klebsiella) were investigated. All strains could decarboxylate at least two amino acids in Moller's broth and in Niven's medium, and the decarboxylase activity was strain specific. In a laboratory medium containing all free amino acids, all strains could produce more than 100 ppm cadaverine, putrescine was produced by 96% of strains. Tyramine and histamine were produced in the lowest concentrations. A positive correlation existed between cadaverine concentration and Enterobacteriaceae counts in cheese, that may have caused the increase in decarboxylase content. This study suggests that it is possible to limit the presence of cadaverine in cheese, thereby controlling the Enterobacteriaceae counts, a sign of contamination during cheese making and/or storage