Open AccessEffect of Weather on the Die-Off of Escherichia coli and Attenuated Salmonella enterica Serovar Typhimurium on Preharvest Leafy Greens following Irrigation with Contaminated Water
Author(s) -
Alexandra Belias,
Adrian Sbodio,
Pilar Truchado,
Daniel Weller,
Janneth Pinzon,
Mariya Skots,
Ana Allende,
Daniel Munther,
Trevor Suslow,
Martin Wiedmann,
Renata Ivanek
Publication year - 2020
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.00899-20
Subject(s) - preharvest , salmonella enterica , salmonella , biology , contamination , population , escherichia coli , food microbiology , bacteria , microbiology and biotechnology , agronomy , horticulture , postharvest , ecology , biochemistry , genetics , demography , sociology , gene
The log-linear die-off rate proposed by FSMA is not always appropriate, as the die-off rates of foodborne bacterial pathogens and specified agricultural water quality indicator organisms appear to commonly follow a biphasic pattern with an initial rapid decline followed by a period of tailing. While we observed substantial variation in the net culturable population levels of Salmonella and E. coli at each time point, die-off rate and FSMA compliance (i.e., at least a 2 log 10 die-off over 4 days) appear to be impacted by produce type, bacteria, and weather; die-off on lettuce tended to be faster than that on spinach, die-off of E. coli tended to be faster than that of attenuated Salmonella , and die-off tended to become faster as relative humidity decreased. Thus, the use of a single die-off rate for estimating time-to-harvest intervals across different weather conditions, produce types, and bacteria should be revised.