BEHAVIOUR OF Aeromonas hydrophila IN SALTED SWORDFISH SAMPLES

Abstract

A challenge test for Aeromonas hydrophila in salted swordfish samples was carried out. Particularly, 24 samples (250g) were experimentally contaminated, salted and stored at two different temperature regimes (fluctuating – F group - and non fluctuating – NF group – regime). The count of A. hydrophila, Enterobacteria and Lactic acid bacteria (LAB) as well as the determination of pH and aw were performed at 0, 19 43, 163, 187, 230, 320 and 368 hours whereas the temperature was monitored continuously by using 6 data-loggers. In both group, the mean concentrations of A. hydrophila did not exceed Log 3 cfu/g and decreased below the mean value of Log 1 cfu/g after 368 hours. However in the F group the A. hydrophila growth was slower and the decrease appeared slightly higher than NF group and this suggests the temperature fluctuations induces a more pronounced behaviour variability of A. hydrophila under stressing conditions.