Survival of Vibrio parahaemolyticus and Aeromonas hydrophila in sea bream (Sparus aurata) fillets packaged under enriched CO2 modified atmospheres

The ability to survive of two pathogens (Vibrio parahaemolyticus and Aeromonas hydrophila) spread over sea bream fillets packaged under different modified atmospheres (MAPs) was studied at 0 °C and 4 °C under refrigerated storage. The atmospheres used were 60% CO2/40% N2, 70% CO2/30% N2 and 80% CO2/20% N2 and a control batch packaged in air. Head space gas analyses, microbial counts and confirming test of pathogenic bacteria were carried out during 16 days. The results obtained showed that all the modified atmospheres studied were effective to reduce the microbial load of sea bream fillets when compared with air packaged samples although small differences were found among MAPs. Temperature storage was the main factor to reduce microbial growth. V. parahaemolyticus was unable to grow at both temperatures, 0 °C and 4 °C (except air batches) while A. hydrophila showed significant growth at 4 °C and microbial inactivation at 0 °C.