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Technological and safety-related properties were analyzed in lactic acid bacteria isolated from Spanish dry-cured sausages in order to select them as starter cultures. In relation to technological properties, all the strains showed significative nitrate reductase activity; Lactobacillus plantarum, Lactobacillus paracasei and 52% of the Enterococcus faecium strains showed lipolytic activity and only Lactobacillus sakei strains (43%) were able to form biofilms. Related to safety aspects, E. faecium strains were the most resistant to antibiotics, whereas, L. sakei strains were the most sensitive. In relation to virulence factors, in the E. faecium strains analyzed, only the presence of efaA gene was detected. The analysis of biogenic amine production showed that most E. faecium strains and L. sakei Al-142 produced tyramine. In conclusion, L. paracasei Al-128 and L. sakei Al-143 strains possess the best properties to be selected as adequate and safe meat starter cultures.

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a b s t r a c tThe occurrence of in vitro production of biogenic amines in bacteria isolated from ice-preserved sardine and mackerel was studied. Biogenic amine production was investigated by means of amino acid decarboxylation by growth on decarboxylase differential medium, biogenic amine detection by thinlayer chromatography (TLC) and decarboxylase gene detection by PCR. Decarboxylase medium overestimate the number of biogenic amine-producer strains, as the production of amine was confirmed by TLC in only five out the 17 presumptive strains. On the producer strains, PCR was used to confirm the presence of the genes encoding the amino acid decarboxylase responsible for the synthesis of these amines. Moreover, biogenic amine-producer bacteria were molecularly identified by sequencing their 16S rRNA. Form sardine, enterobacteria producing simultaneously several biogenic amines were isolated. A Kluyvera intermedia strain producing histamine, putrescine and cadaverine, and an Enterobacter asburiae strain producing only the diamines cadaverine and putrescine were identified. From mackerel, lactic acid bacteria from the Enterococcus durans species producing tyramine were isolated. This study constitutes the first description of the presence on these putatively harmful species on ice-preserved sardine and mackerel.