Microbiological survey of imported produce available at retail across Canada

• Published in: International journal of food microbiology 2013-03, Vol.162 (2), p.135-142
• Main Authors: Allen, Kevin J., Kovacevic, Jovana, Cancarevic, Ana, Wood, Jayde, Xu, Jieqing, Gill, Bradford, Allen, Jennifer K., Mesak, Lili R.
• Format: Article
• Language: English
• Subjects: Anti-Infective Agents - pharmacology; Antimicrobial resistance; Bacteria - drug effects; Bacteria - isolation & purification; Biological and medical sciences; Canada; Colony Count, Microbial; Drug Resistance, Microbial - physiology; Enterococcus; Enterococcus faecalis; Enterococcus faecium; Escherichia coli; Food industries; Food Microbiology; Food Safety; Foodborne pathogens; Fundamental and applied biological sciences. Psychology; General aspects; Hygiene and safety; Imported produce; Microbiological quality; Salmonella; Spinacia oleracea; Spinacia oleracea - microbiology; Vegetables - microbiology
• ISSN: 0168-1605; 1879-3460
• DOI: 10.1016/j.ijfoodmicro.2013.01.010

Increasing consumption and year-round consumer demand for fresh, minimally processed green vegetables have been observed in Canada and other developed countries. However, in the past two decades, produce has been increasingly implicated in outbreaks and correspondingly recognized as a vector for the transmission of pathogenic microorganisms. To this end, we examined the microbiological quality of imported produce available at retail across Canada during a period of limited domestic availability. In total, 106 samples obtained from five Canadian cities were purchased from retail outlets and subjected to microbiological analyses, including aerobic plate (APC) and coliform counts, and enrichments for enterococci, indicator Escherichia coli, E. coli O157:H7 and Salmonella spp. Also, recovered Enterococcus faecalis and Enterococcus faecium were screened for antimicrobial resistance (AMR). Overall, samples included herbs (n=61), leafy greens (n=25), and spinach (n=20) deriving from five countries (Columbia, Dominican Republic, Guatemala, Mexico, and the United States [US]). APCs were consistent across commodities regardless of country, ranging from mean log10CFU/g of 6.1 to 7.4, with no significant differences observed. Excluding a single leafy green sample from Guatemala, the lowest prevalence of coliforms was for Mexican herbs (22.2%), with a high of 66.7% on US leafy greens. With the exception of spinach, concentrations of coliforms varied widely, ranging from undetectable to too numerous to count (>8.5log10CFU/g). Of the commodities assessed, Mexican and US spinach had the lowest coliform concentrations (undetectable to 4.0log10CFU/g). Organic herbs and conventional leafy greens possessed significantly lower (p