Current Research in Food Science | |
Inactivation of Salmonella enterica on post-harvest cantaloupe and lettuce by a lytic bacteriophage cocktail | |
Pascal Delaquis1  Lawrence Goodridge2  Catherine W.Y. Wong3  Karen Fong3  Siyun Wang3  Roger C. Lévesque4  | |
[1] Agriculture and Agri-Food Canada, 4200 Highway 97, Summerland, BC, V0H 1Z0, Canada;Department of Food Science and Agricultural Chemistry, McGill University, Montréal, QC, Canada;Department of Food Science, University of British Columbia, 2205 East Mall, Vancouver, BC, V6R 1Z4, Canada;Institute for Integrative and Systems Biology, Université Laval, Québec City, QC, Canada; | |
关键词: Salmonella enterica; Bacteriophage; Post-harvest; Lettuce; Cantaloupe; Biocontrol; | |
DOI : | |
来源: DOAJ |
【 摘 要 】
Salmonella enterica (S. enterica) is a causative agent of multiple outbreaks of foodborne illness associated with fresh produce, including pre-cut melon and leafy vegetables. Current industrial antimicrobial interventions have been shown to reduce microbial populations by <90%. Consequently, bacteriophages have been suggested as an alternative to chemical sanitizers. Seven S. enterica strains from four serovars (105 CFU/mL) were separately inoculated onto excised pieces of Romaine lettuce leaf and cantaloupe flesh treated with a five-strain bacteriophage cocktail 24 h before S. enterica inoculation. S. enterica, total aerobic populations and water activity were measured immediately after inoculation and after 1 and 2 days of incubation at 8 °C. The efficacy of the bacteriophage cocktail varied between strains. Populations of S. enterica Enteritidis strain S3, S. Javiana S203, S. Javiana S200 were reduced by > 3 log CFU/g and S. Newport S2 by 1 log CFU/g on both lettuce and cantaloupe tissues at all sampling times. In contrast, populations of strains S. Thompson S193 and S194 were reduced by 2 log CFU/g on day 0 on lettuce, but were not significantly different (P > 0.05) from the controls thereafter, S. Newport S195 populations were reduced on lettuce by 1 log CFU/g on day 0 and no reductions were found on cantaloupe tissue. Both aerobic populations and water activity were higher on cantaloupe than on lettuce. The water activity of lettuce decreased significantly (P < 0.05) from 0.845 ± 0.027 on day 0–0.494 ± 0.022 on day 1, but that of cantaloupe remained between 0.977 and 0.993 from day 0–2. The results of this study showed that bacteriophages can reduce S. enterica populations on lettuce and cantaloupe tissues but that the magnitude of the effect was strain-dependent.
【 授权许可】
Unknown