Journal of Food and Nutrition Research
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Journal of Food and Nutrition Research. 2020, 8(1), 63-73
DOI: 10.12691/jfnr-8-1-9
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Prevalence of Enterobacteriaceae on Ready to Eat Salads, Drinking Water and Surfaces in Food Markets of Maputo, Mozambique

Glória Alberto Manhique1, 2, , Claudia Titze Hessel1, Erika M DU Plessis3, Stefani Machado Lopes1, Susana de Oliveira Elias1, Eduardo César Tondo1 and Lise Korten3

1Laboratory of Food Microbiology and Food Control, Institute of Food Science and Technology, Federal University of Rio Grande do Sul - ICTA /UFRGS, 9500, Bento Gonçalves Avenue, building 43212, Campus do Vale, Agronomy, Porto Alegre, RS, Brazil

2Technical Higher School - (ESTEC-Mozambique), João Raposo Beirão Street, 135, PO Box, 3276, Maputo/Mozambique

3Centre of Excellence in Food Security, Department of plant and Soil Sciences, University of Pretoria, Hatfield, Pretoria 0002, South Africa

Pub. Date: January 26, 2020

Cite this paper:
Glória Alberto Manhique, Claudia Titze Hessel, Erika M DU Plessis, Stefani Machado Lopes, Susana de Oliveira Elias, Eduardo César Tondo and Lise Korten. Prevalence of Enterobacteriaceae on Ready to Eat Salads, Drinking Water and Surfaces in Food Markets of Maputo, Mozambique. Journal of Food and Nutrition Research. 2020; 8(1):63-73. doi: 10.12691/jfnr-8-1-9


Vegetable salads constitute an important component of many meals worldwide. However there is concern for their safety and microbiological quality because they have been implicated in outbreaks of many foodborne diseases, especially in developing countries. In Mozambique, the knowledge of the microbiological quality and virulence genes of bacterial isolates from ready-to-eat (RTE) salads is limited. This study aimed to evaluate the prevalence of Enterobacteriaceae on RTE lettuce, drinking water and surfaces in food markets of Maputo, Mozambique. A total of 35 samples of RTE lettuce salads and 42 drinking water samples were collected from 35 food vendors, in addition to 105 swabs of hands, knives and bowls from seven markets in Maputo City, Mozambique. The prevalence of Enterobacteriaceae bacterial isolates from the collected samples was determined using plate counts method following ISO 21528-2 and ISO 21528-1 (for drinking water). The purified isolates were identified using a matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF-MS). A total of 219 isolates were obtained. Enterobacter isolates (45.2%) were the predominant species. Enterobacteriaceae counts ranged from 0.52 to 6.98log CFU/g. There was no statistically significant correlation between bacteriological counts on RTE lettuce salads and swabs. However, there were significant differences among the numbers of Enterobacteriaceae detected in water for other samples. The prevalence of Escherichia coli was observed in fewer samples, a remarkable tendency of the presence of this bacterium was found in the utensils. The E. coli isolates obtained in this study tested negative for the presence of virulence genes (stx1F, stx1R, stx2F, stx2R). These findings provide valuable background information that can support food safety decisions and confirm that the vast majority of vendors do not sanitize utensils effectively.

food markets indicators MALDI-TOF-MS hygiene quality foodborne pathogens

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