Effectiveness of different sanitizers in inactivating E. coli O157:H7 in Tomato and Cucumber

Abstract

Fresh produce is popular worldwide because it is recognized as an important source of nutrients, vitamins and fiber for humans. However, in the last two decades outbreaks of food borne illness and cases associated with fresh produce have increased significantly. This study was conducted to evaluate the efficacy of acidic electrolyzed water (EO) and alkaline water (AlcO), 200-ppm chlorine water, 3% H 2 O 2 and/or sterile distilled water wash in reducing Escherichia coli O157:H7 on the surface of dip-inoculated tomato and cucumber. Inoculated sample (tomato, cucumber) were dipped in 200 ml of electrolyzed acidic or alkali water, or 200 ppm chlorine water, or 3% H 2 O 2 and/or sterile distilled water and hand rubbed for 90 seconds followed by second wash with sterile distilled water for 90 seconds to minimize the residual effect. Approximately 2.0 log CFU/g reduction was observed when washed with acidic electrolyzed water (EO) and alkaline water (AlcO). On the other hand, approximately 3.0-4.0 log CFU/g reduction was observed while washing with chlorine water and 3% H 2 O 2. Washing with distilled water found ineffective in reducing the pathogen. Prevalence of total microbial population, coliforms, Salmonella enteriditis, E. coli O157:H7, Listeria monocytogenes, Yersinia enterocolitica was also observed in non-spiked samples (tomato, cucumber). It was found that total microbial population, coliform bacteria and other pathogens varied among different samples depending on the location and type of samples. However, no Salmonella spp., were found in the tested samples. The results revealed that 3% H 2 O 2 or 200 ppm chlorine water gave better reduction than that of acidic electrolyzed water and alkali water.

A study on the prevalence of heavy metals, pesticides, and microbial contaminants and antibiotics resistance pathogens in raw salad vegetables sold in Dhaka, Bangladesh

“…Again, foodborne illness due to contaminated vegetables increased many folds worldwide and many research studies reported that the presence of pathogenic bacteria like E. coli O157:H7, Salmonella spp., Listeria spp., Staphylococcus spp., Yersinia enterocolitica etc. in various fresh vegetable samples of Dhaka city markets (Islam et al., 2015; Jeddi et al., 2014; Kabir et al., 2014). In addition, when these pathogens were found resistant to multiple antibiotics, could pose significant public health risk and resistance of pathogenic bacteria could leads to the anti-infective therapy of both humans and animals (Lai et al., 2016).…”

Isolation, identification and antibiogram of verotoxin producing Escherichia coli from raw salad vegetables at Jashore, Bangladesh

“…Out of the 119 samples, E. coli was isolated from 55 samples, with a prevalence of 46% for this investigation. Isolation of E. coli from raw vegetables is also published in Dhaka city by several researchers (Islam et al, 2015;Kabir et al, 2014). But the prevalence ratio is relatively low.…”

Use of Non-Chlorine Sanitizers in Improving Quality and Safety of Marketed Fresh Salad Vegetables

“…Lettuce, tomato [12,13] Shigella spp. Lettuce, salad vegetables [14] Yersinia enterocolitica Carrots, cucumber, lettuce, and tomatoes [15][16][17] Viruses Hepatitis A and Norovirus Lettuce [18,19] Protozoa Cryptosporidium spp. and Cyclospora spp.…”