Microbiological safety of ready-to-eat fresh-cut fruits and vegetables sold on the Canadian retail market.

Following implementation of Health Canada's Policy on Listeria monocytogenes in Ready-to-Eat Foods by Canadian food safety authorities in 2011, a four-year study (2012-2016) was carried out to gain baseline information on the occurrence of bacterial pathogens, notably the prevalence and levels of Listeria monocytogenes (L. monocytogenes) in various product types of ready-to-eat (RTE) fresh-cut fruits and fresh-cut vegetables sold at retail in Canada. A total of 10,070 pre-packaged samples, including 4691 fresh-cut fruit and 5379 fresh-cut vegetable samples were collected from retail stores across Canada and analyzed for bacterial pathogens and generic Escherichia coli (E. coli). Salmonella species (spp.), E. coli O157:H7, Shigella and Campylobacter were not detected in any of the tested samples. L. monocytogenes was identified in 0.51% (95% CI [0.34, 0.76]) of the fresh-cut fruit and in 0.24% (95% CI [0.14, 0.41]) of the fresh-cut vegetable samples. Of the 37 L. monocytogenes positive samples identified, levels of L. monocytogenes <5 CFU/g, 5-<100 CFU/g, and ≥100 CFU/g were found in 67.6% (25/37), 24.3% (9/37) and 8.1% (3/37) of the samples, respectively. The results of this study indicate that the vast majority of fresh-cut fruits and vegetables sold on the Canadian retail market are safe for consumption. However, contamination by L. monocytogenes can infrequently occur in fresh-cut fruits and vegetables, with certain types of fresh-cut fruits (i.e., melons, apples) and vegetables (i.e., mushrooms, cauliflower) being more likely to be contaminated than others. Safe handling practices are recommended for producers, retailers and consumers including storage at refrigerated temperatures.

Zhang H ，Yamamoto E ，Murphy J ，Locas A ... -  《-》

Microbiological quality of fresh, minimally-processed fruit and vegetables, and sprouts from retail establishments.

Abadias M ，Usall J ，Anguera M ，Solsona C ，Viñas I ... -  《INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY》

Microbiological Quality and Safety of Fresh Fruits and Vegetables at Retail Levels in Korea.

The aim of this study was to evaluate the microbiological quality and safety of fresh produce at retail level in Korea in order to periodically update information and establish available risks associated with consumption of fresh fruits and vegetables. The samples from different markets located in 3 provinces of South Korea were collected. The protocol in the Korean Food Standards Codex was applied and generic Escherichia coli, coliforms, aerobic mesophilic bacteria (AMB), and yeast and mold (YM) in 360 packaged and unpackaged fresh fruits and vegetables were analyzed. Presence of pathogens was examined using real-time polymerase chain reaction (q-PCR) after enrichment of samples. For all, the microbial counts ranged from 1.7 to 10.6 log cfu/g for AMB, 2.2 to 7.9 log cfu/g for coliforms, and 5.5 to 7.9 log cfu/g for YM. Three lettuce samples were contaminated by E. coli with a bacterial load ranging from 2 to 4 log cfu/g. Salmonella spp. were not detected in any fresh produce. Listeria monocytogenes, E. coli O157:H7, and Staphylococcus aureus were found in 1 (0.6%), 3 (0.8%), and 5 (1.4%) fresh produce samples, respectively. Bacillus cereus (50.3%) and Clostridium perfringens (13.3%) had the highest prevalence. These results indicate the need for employing strict control measures and developing preventive strategies to improve the quality and safety of fresh produce in Korea.

Tango CN ，Wei S ，Khan I ，Hussain MS ，Kounkeu PN ，Park JH ，Kim SH ，Oh DH ... -  《-》

Microbiological study of ready-to-eat salad vegetables from retail establishments uncovers a national outbreak of salmonellosis.

Sagoo SK ，Little CL ，Ward L ，Gillespie IA ，Mitchell RT ... -  《JOURNAL OF FOOD PROTECTION》

Prevalence and characterization of foodborne pathogens isolated from fresh-cut fruits and vegetables in Beijing, China.

Pre-cut fresh fruits and vegetables are highly appealing to consumers for their convenience, however, as they are highly susceptible to microbial contamination in processing, the potential risks of foodborne illnesses to public health are not negligible. This study aimed to assess the prevalence, antibiotic susceptibility and molecular characteristics of major foodborne pathogens (Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella) isolated from fresh-cut fruits and vegetables in Beijing, China. 86 stains were isolated from 326 samples, with S. aureus being the highest prevalence (15.38 %), followed by E. coli (9.23 %) and L. monocytogenes (1.85 %), while no Salmonella was detected. The prevalence by type of food indicated that fruit trays and mixed vegetables were more susceptible to contamination by pathogens. 98 % of S. aureus were resistant to at least of one antibiotic, and showed a high resistance rate to benzylpenicillin (90 %) and oxacillin (48 %). Among 25 E. coli isolates, 57.67 % of which exhibited multi-drug resistance, with common resist to trimethoprim/sulfamethoxazole (66.67 %) and ampicillin (63.33 %). A total of 9 sequence types (STs) and 8 spa types were identified in 35 S. aureus isolates, with ST398-t34 being the predominant type (42.86 %). Additionally, analysis of 25 E. coli isolates demonstrated significant heterogeneity, characterized by 22 serotypes and 18 STs. Genomic analysis revealed that 5 and 44 distinct antibiotic resistance genes (ARGs) in S. aureus and E. coli, respectively. Seven quinolone resistance-determining regions (QRDRs) mutations were identified in E. coli isolates, of which GyrA (S83L) was the most frequently detected. All the S. aureus and E. coli isolates harbored virulence genes. ARGs in S. aureus and E. coli showed a significant positive correlation with plasmids. Furthermore, one L. monocytogenes isolate, which was ST101 and serogroupIIc from watermelon sample, harbored virulence genes (inlA and inlB) and LIPI-1 pathogenic islands (prfA, plcA, hly and actA), which posed potential risks for consumer's health. This study focused on the potential microbial risk of fresh-cut fruits and vegetables associated with foodborne diseases, improving the scientific understanding towards risk assessment related to ready-to-eat foods.

Bai Y ，Li J ，Huang M ，Yan S ，Li F ，Xu J ，Peng Z ，Wang X ，Ma J ，Sun J ，Yang B ，Cui S ... -  《-》