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Tomatoes have been implicated in various microbial disease outbreaks and are considered a potential vehicle for foodborne pathogens. Traceback studies mostly implicate contamination during production and/or processing. The microbiological quality of commercially produced tomatoes was thus investigated from the farm to market, focusing on the impact of contaminated irrigation and washing water, facility sanitation, and personal hygiene. A total of 905 samples were collected from three largescale commercial farms from 2012 through 2014. The farms differed in water sources used (surface versus well) and production methods (open field versus tunnel). Levels of total coliforms and Escherichia coli and prevalence of E. coli O157:H7 and Salmonella Typhimurium were determined. Dominant coliforms were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. No pathogens or E. coli were detected on any of the tomatoes tested throughout the study despite the high levels of coliforms (4.2 to 6.2 log CFU/g) present on the tomatoes at the market. The dominant species associated with tomatoes belonged to the genera Enterobacter, Klebsiella, and Citrobacter. Water used on the farm for irrigation considered not fit for purpose according to national agricultural irrigation standards, with high E. coli levels resulting from either a highly contaminated source water (river water at 3.19 log most probable number [MPN]/100 ml) or improper storage of source water (stored well water at 1.72 log MPN/100 ml). Salmonella Typhimurium was detected on two occasions on a contact surface in the processing facility of the first farm in 2012. Contact surface coliform counts were 2.9 to 4.8 log CFU/cm(2). Risk areas identified in this study were water used for irrigation and poor sanitation practices in the processing facility. Implementation of effective food safety management systems in the fresh produce industry is of the utmost importance to ensure product safety for consumers.

Decay and quality loss severely affect the marketability of fresh zucchini. Zucchinis are easily damaged during harvesting, -handling and -storage and no commercial treatment is currently available that can protect the fruit from desiccation, quality loss and decay. The aim of this study was to compare different environmentally friendly dipping treatments (CaCl 2 , Aloe vera, warm water, chitosan, ascorbic-and citric acid) to retain quality of fresh zucchini. Treated fruit were evaluated for physiological, sensory and microbiological parameters after storage for seven and 14 days at 5.8°C and 85% relative humidity. The CaCl 2 , Aloe vera and warm water treatments were the most effective in maintaining firmness and preventing an increase in the total microflora of the fruit. The outcome of this study shows that alternative control methods have potential for effective quality maintenance of fresh zucchini. Future studies should focus on alternative packaging materials in combination with these treatments. PRACTICAL APPLICATIONSZucchinis are rich in carbohydrates, minerals and vitamins and a good nutritional additive to a balanced and healthy diet. Recent observations at retail level showed preventable quality losses, indicating the need to improve postharvest technologies for retaining the overall standard of the product after harvest and during the supply chain.2 Quality parameters include firm texture, shiny, dark-green skin color, and freedom from shrivel and mechanical injuries. The assessment of different environmentally friendly dipping treatments indicated that CaCl 2 , Aloe vera and warm water treatments could lead to improved quality maintenance of zucchinis. Practical applications stemming from these results include the ability to extend shelf-life and preserve the microbiological profile of these fruit after harvest. These treatments may serve as alternatives to chemical or synthetic treatments and may be considered as an inclusion to current postharvest management practices.

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Basil has been implicated in a number of microbe-associated foodborne illnesses across the world, and the source of contamination has often been traced back to the production and/or processing stages of the supply chain. The aim of this study was to evaluate the microbiological quality of fresh basil from the point of production to the retail outlet in the Gauteng and Northwest Provinces of South Africa. A total of 463 samples were collected over a 3-month period from two large-scale commercial herb producing and processing companies and three retail outlets. The microbiological quality of the samples was assessed based on the presence or absence of Escherichia coli O157:H7 and Salmonella Typhimurium and the levels of the indicator bacteria E. coli and total coliforms. Salmonella Typhimurium was detected on four basil samples (0.9%) arriving at the processing facility and at dispatch, but no E. coli O157:H7 was detected throughout the study. Total coliform counts were 0.4 to 4.1 CFU/g for basil, 1.9 to 3.4 log CFU/ml for water, and 0.2 to 1.7 log CFU/cm(2) for contact surfaces, whereas E. coli was detected in the water samples and only once on basil. The Colilert-18 and membrane filter methods were used to analyze water samples, and a comparison of results revealed that the Colilert-18 method was more sensitive. Strong evidence suggests that high numbers of coliforms do not necessarily indicate the presence of Salmonella Typhimurium. The study results highlight the importance of effective implementation of food safety management systems in the fresh produce industry.

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