Effects of CO2 on the resuscitation of Listeria monocytogenes injured by various bactericidal treatments.
To assure the microbiological safety and quality of a food product, a combination of preservation hurdles is often used. Therefore, the effects of carbon dioxide at concentrations of 0, 20, 40 and 60% in modified atmospheres on the resuscitation of Listeria monocytogenes cells injured by mild bactericidal treatments during storage at 7 degrees C were examined. The bactericidal treatments were intense light pulses (ILP), chlorine dioxide (ClO(2)), lactic acid (LA) and heat. The results indicated additional bactericidal effects of CO(2) on cultures treated with LA, ClO(2) and ILP, with additional reductions in viable L. monocytogenes of 0.5-1.0 log cfu/ml. Lag phase duration was significantly different between the different treatments, with non-treated cells having the shortest lag phase, followed by that of heat, intense light pulses, lactic acid and finally ClO(2) treated cells. Maximum growth rate was also estimated and results showed a negative correlation with increasing CO(2) concentrations. A relationship was found between the amount of sub-lethally damaged cells after a mild inactivation treatment and the lag phase duration in the CO(2) environment. Current findings demonstrate the possibility that combining mild decontamination treatments and packaging in a CO(2) enriched environment could reduce the risk of L. monocytogenes infections in food due to an extension of the lag phase.
Van Houteghem
Nancy
N
Department of Food Safety and Food Quality, Laboratory of Food Microbiology and Food Preservation, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
Devlieghere
Frank
F
Rajkovic
Andreja
A
Gómez
Sandra Maria Osés
SM
Uyttendaele
Mieke
M
Debevere
Johan
J
D002245:Carbon Dioxide / Q000494:pharmacology*; D017606:Chlorine Compounds / Q000494:pharmacology; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004305:Dose-Response Relationship, Drug; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D018857:Food Packaging / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D005520:Food Preservatives / Q000494:pharmacology; D006358:Hot Temperature; D006801:Humans; D019344:Lactic Acid / Q000494:pharmacology; D008027:Light; D008089:Listeria monocytogenes / Q000187:drug effects / Q000254:growth & development*; D008954:Models, Biological; D010087:Oxides / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors
D017606:Chlorine Compounds; D005520:Food Preservatives; D010087:Oxides; D002245:Carbon Dioxide; D019344:Lactic Acid; C025109:chlorine dioxide