TY - JOUR

T1 - Survival of lactic acid and chlorine dioxide treated Campylobacter jejuni under suboptimal conditions of pH, temperature and modified atmosphere

AU - Smigic, Nada

AU - Rajkovic, Andreja

AU - Nielsen, Dennis Sandris

AU - Arneborg, Nils

AU - Siegumfeldt, Henrik

AU - Devlieghere, Frank

PY - 2010

Y1 - 2010

N2 - As mild decontamination treatments are gaining more and more interest due to increased consumer demands for fresh foods, it is of great importance to establish the influence of decontamination treatments on the subsequent bacterial behaviour under suboptimal storage conditions. For this purpose Campylobacter jejuni cells treated with lactic acid (LA, 3% lactic acid, pH 4.0, 2 min) or chlorine dioxide (ClO(2), 20 ppm, 2 min) were inoculated in Bolton broth (pH 6.0) and incubated under 80% O(2)/20% N(2), 80% CO(2)/20% N(2), air or micro-aerophilic (10% CO(2)/85% N(2)/5% O(2)) atmosphere, at 4 degrees C during 7 days. Treatment with water served as a control. The most suppressive atmosphere for the survival of C. jejuni was O(2)-rich atmosphere, followed by air, micro-aerophilic and CO(2)-rich atmosphere. The survival of C. jejuni was dependent on the type of initial decontamination treatment, with water treated cells showing the greatest survival followed by LA and ClO(2) treated cells. Intracellular pH (pH(i)) of individual C. jejuni cells was determined using Fluorescence Ratio Imaging Microscopy (FRIM). At all tested conditions, different subpopulation of the cells could be distinguished based on their pH(i) values. The pH(i) response was independent on the surrounding atmosphere since similar distribution of the subpopulations was observed for all tested atmospheres. However, the pH(i) response was dependent on the initial decontamination treatment. The investigation of intracellular parameters gave an insight into pathogen behaviour under stressful conditions at intracellular level. The results obtained in this study highlighted the importance of combining decontamination technologies with subsequent preservation techniques to the control survival and growth of foodborne pathogens.

AB - As mild decontamination treatments are gaining more and more interest due to increased consumer demands for fresh foods, it is of great importance to establish the influence of decontamination treatments on the subsequent bacterial behaviour under suboptimal storage conditions. For this purpose Campylobacter jejuni cells treated with lactic acid (LA, 3% lactic acid, pH 4.0, 2 min) or chlorine dioxide (ClO(2), 20 ppm, 2 min) were inoculated in Bolton broth (pH 6.0) and incubated under 80% O(2)/20% N(2), 80% CO(2)/20% N(2), air or micro-aerophilic (10% CO(2)/85% N(2)/5% O(2)) atmosphere, at 4 degrees C during 7 days. Treatment with water served as a control. The most suppressive atmosphere for the survival of C. jejuni was O(2)-rich atmosphere, followed by air, micro-aerophilic and CO(2)-rich atmosphere. The survival of C. jejuni was dependent on the type of initial decontamination treatment, with water treated cells showing the greatest survival followed by LA and ClO(2) treated cells. Intracellular pH (pH(i)) of individual C. jejuni cells was determined using Fluorescence Ratio Imaging Microscopy (FRIM). At all tested conditions, different subpopulation of the cells could be distinguished based on their pH(i) values. The pH(i) response was independent on the surrounding atmosphere since similar distribution of the subpopulations was observed for all tested atmospheres. However, the pH(i) response was dependent on the initial decontamination treatment. The investigation of intracellular parameters gave an insight into pathogen behaviour under stressful conditions at intracellular level. The results obtained in this study highlighted the importance of combining decontamination technologies with subsequent preservation techniques to the control survival and growth of foodborne pathogens.

KW - Former LIFE faculty

KW - Campylobacter jejuni

KW - Lactic acid

KW - Chlorine dioxide

KW - Modified atmosphere

KW - Intracellular pH

U2 - 10.1016/j.ijfoodmicro.2010.01.026

DO - 10.1016/j.ijfoodmicro.2010.01.026

M3 - Journal article

VL - 141

SP - S140-S146

JO - International Journal of Food Microbiology

JF - International Journal of Food Microbiology

SN - 0168-1605

IS - Suppl. 1

ER -