Given that it should be aware of the nutritional benefits, resulting from the consumption of fresh fruits and vegetables consumed raw and/or minimally processed, comparing the efficacy of different individual sanitizing methods against the major food-borne pathogens localized in fresh commodities is of much importance; these products are easily vulnerable to the microbial contamination. In this review, the current propensity of alternative sanitizing methods was introduced, as well as principal elements for deteriorating the cleaning effects were also discussed. Chlorine-based-sanitizers exhibited the microbial reduction of <1.12 log CFU/g on fruits and vegetables. Most of aqueous disinfectants showed ≤3.01 log-redcutions against a variety of microorganisms inoculated on fresh commodities. Similarly, several physical technologies such as hydrostatic pressure and ultraviolet light were effective for reducing surviving bacterial cells could recover and grow rapidly during the whole processing, posing a potential risk of causing food-borne outbreaks associated with the fresh products. The invasion and subsequent localization of the organisms into the inner parts of products, interactions between the microbial cell and food-contacting surfaces, as well as development of biofilms could restrict the antimicrobial activity of the currently used approaches.

There has been limited information available on the behavior of and as a function of higher levels of NaCl in combination with acidic pH. In the present study, bacterial suspensions were transferred into artificial seawater (pH 4-7) microcosms containing 0.75% NaCl and supplemented with 5, 10, and 30% NaCl, respectively. Each of and was inoculated in these microcosms and fermented seafood, and then stored at 4 °C until the microbial populations reached below the detectable levels on agar plates (thiosulphate-citrate-bile salts-sucrose agar and tryptic soy agar amended with 3% NaCl). Consequently, ATCC 27969, ATCC 33844, and ATCC 33815 rapidly reached the viable-but-nonculturable (VBNC) state with increasing levels (≤30%) of NaCl at 4 °C. Within seven days, these pathogens in seafood appeared to enter the VBNC state at 4 °C, as shown by the fluorescence microscopic assay.

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This study shows that depending on the type of acid, the addition of NaCl can increase the resistance of Sh. flexneri to acid treatments. This may provide useful information for developing methods of preserving acidified foods.

This study was conducted to investigate the antibacterial effect of various essential oils (EOs) against pathogens and fresh produce spoilage bacteria using the agar disc diffusion method and 96‐well dilution method. Moreover, the antibacterial effect of EOs to reduce the level of total mesophilic microorganisms in fresh leaf lettuce and radish sprouts was determined by dipping method. Furthermore, membrane damage of two pathogens before and after treatment with effective EOs was determined using the fluorescent dye propidium iodide (PI) staining method. The results showed that thyme‐1, thyme‐2 and tea tree‐2 oils demonstrated the strongest antibacterial effect against 18 strains of pathogens, except for Pseudomonas aeruginosa, in the agar disc diffusion method. Thyme‐1 oil showed the strongest antibacterial effect against spoilage bacteria. The dipping treatment results showed that oregano‐2 oil was the most effective at maintaining reduced levels of total mesophilic microorganisms in fresh produce compared with control, although it affected the quality of both vegetables after treatment. The results showed that treatment with clove bud, cinnamon‐2 and oregano‐2 oils led to PI values significantly greater than that of untreated cell. Practical Applications Natural essential oil solutions can be used for the disinfection of fresh produce as an alternative to chlorine, and oregano oil could be used as an alternative to synthetic sanitizers, classically applied in fresh produce.

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Viable but nonculturable (VBNC) Vibrio parahaemolyticus cannot be detected by the standard cultivation‐based methods. In this study, commonly used viability assessment methods were evaluated for the detection of V. parahaemolyticus in a VBNC state. Vibrio parahaemolyticus cells exposed to nutrient deficiency at cold temperature were used for epifluorescence microscopy with SYTO9 and propidium iodide (PI) staining and real‐time polymerase chain reaction (qPCR) with propidium monoazide (PMA), and its resuscitative ability was determined by a temperature upshift in freshly prepared artificial sea water (ASW; pH 7) fluids. Viable cells with intact membranes always exceeded 5·0 log CFU per ml in ASW microcosms at 4°C. After 80 days, cycle thresholds for V. parahaemolyticus ATCC 27969 were 16·15–16·69. During cold‐starvation, PMA qPCR selectively excluded DNAs from heat‐killed cells. However, there may be some penetration of PMA into undamaged cells that persisted in ASW for 150 days, as evidenced by their ability to resuscitate from a VBNC state after a temperature upshift (25°C); V. parahaemolyticus ATCC 33844 and V. parahaemolyticus ATCC 27969 were successfully reactivated from a VBNC state in ASW microcosms containing <5% NaCl, following enrichment in ASW medium (pH 7). Significance and Impact of the Study Few studies have evaluated the characteristics of and detection methods for viable but nonculturable (VBNC) Vibrio parahaemolyticus induced by cold‐starvation. Currently, VBNC cells are routinely detected by SYTO9 and propidium iodide double staining. However, viable cell counts might be overestimated by this approach, suggesting that the fluorescence dyes may be ineffective for accurately determining the viability of bacterial cells. We demonstrated that quantitative real‐time polymerase chain reaction with propidium monoazide, which selectively permeates damaged cell membranes, can be used to obtain viable cell counts of V. parahaemolyticus after its evolution to a VBNC state under cold‐starvation conditions.