Approved for publication as Journal Article No. J-12190 of the Mississippi Agriculture and Forestry Experiment Station (MAFES), Mississippi State Univ.
Microbial Quality and Safety of X-Ray Irradiated Fresh Catfish (Ictalurus punctatus) Fillets Stored under CO2 Atmosphere
Article first published online: 17 AUG 2012
© 2012 Institute of Food Technologists®
Journal of Food Science
Volume 77, Issue 9, pages M533–M538, September 2012
How to Cite
Gawborisut, S., Kim, T.J., Sovann, S. and Silva, J.L. (2012), Microbial Quality and Safety of X-Ray Irradiated Fresh Catfish (Ictalurus punctatus) Fillets Stored under CO2 Atmosphere. Journal of Food Science, 77: M533–M538. doi: 10.1111/j.1750-3841.2012.02866.x
- Issue published online: 7 SEP 2012
- Article first published online: 17 AUG 2012
- MS 20120241 Submitted 2/16/2012, Accepted 6/18/2012.
- CO2 atmosphere;
- Listeria monocytogenes;
- Salmonella Typhimurium;
- spoilage bacteria;
Abstract: The effect of low-dose X-ray irradiation (0, 2, and 3 kGy) on pathogens, spoilage bacteria (psychrotrophic, anaerobic, and lactic acid bacteria), and physicochemical parameters of iced catfish fillets stored under carbon dioxide (CO2) atmosphere were studied. Irradiation of 2 or 3 kGy eliminated all Listeria monocytogenes (4.8 log CFU/g) and Salmonella Typhimurium (4.7 log CFU/g) while CO2 atmosphere alone showed less than 1 log reduction on Salmonella Typhimurium. There was no recovery of either pathogen for the experimental period. Regardless of dose, irradiation showed 2 log reduction on psychrotrophic, anaerobic, and lactic acid bacteria for 24 d. Further post-irradiation reductions of spoilage bacteria were observed. Spoilage bacteria on catfish fillets treated with 2 kGy irradiation regained their growth after 16 d of storage. However, catfish fillets exposed to 3 kGy did not show growth of spoilage bacteria throughout the experimental period (24 d). Irradiation (2 or 3 kGy) increased pH and TBARS, and decreased Hunter “b” values but produced no effect on water holding capacity and texture. Shelf life of catfish fillets exposed to 2 or 3 kGy irradiation could be extended by more than 24 d at 2 to 4 °C, with the added safety of possibly eliminating pathogens.