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The growing concerns regarding foodborne illnesses related to fresh produce accentuate the necessity for innovative material solutions, particularly on surfaces that come into close contact with foods. This study introduces a sustainable, efficient, and removable antimicrobial and antifouling coating ideally suited for hydrophobic food-contact surfaces such as low-density polyethylene (LDPE). Developed through a crosslinking reaction involving tannic acid, gelatin, and soy protein hydrolysate, these coatings exhibit proper stability in aqueous washing solutions and effectively combat bacterial contamination and prevent biofilm formation. The unique surface architecture promotes the formation of halamine structures, enhancing antimicrobial efficacy with a rapid contact killing effect and reducing microbial contamination by up to 5 log10 cfu·cm-2 against both Escherichia coli (Gram-negative) and Listeria innocua (Gram-positive). Notably, the coatings are designed for at least five recharging cycles under mild conditions (pH6, 20 ppm free active chlorine) and can be easily removed with hot water or steam to refresh the depositions. This removal process not only conveniently aligns with existing sanitation protocols in the fresh produce industry but also facilitates the complete eradication of potential developed biofilms, outperforming uncoated LDPE coupons. Overall, these coatings represent sustainable, cost-effective, and practical advancements in food safety and are promising candidates for widespread adoption in food processing environments.

Introduction: Integrated crop-livestock systems (ICLS) use animals to graze crop residues or cover crops before planting fresh produce and provide ecosystem services to support organic vegetable production. However, there is a risk of foodborne pathogen transfer to fresh produce because grazing may introduce enteric foodborne pathogens into the soil via animal feces, which may subsequently be transferred to the produce. Methods: To examine the effect of cover crop use and the risk of cover crop grazing on the contamination of soil and produce by foodborne pathogens in ICLS, a three-year (2019–2021) experimental study was conducted in organically managed plots, which were assigned three different treatments (fallow without cover crop or grazing, cover crop without grazing, or cover crop with grazing by sheep) in a maize/tomato rotation. During the three years of the experiment, a total of 184 pre- and post-graze fecal samples and 96 samples of tomatoes were collected to test for foodborne pathogens (Escherichia coli O157, non-O157 Shiga toxin-producing Escherichia coli (STEC), and Listeria (L.) monocytogenes). Soil samples were collected monthly until 126–171 days after grazing (824 in total) to examine the presence of foodborne pathogens, and generic E. coli (MPN/g) was quantified to compare its persistence among the three treatments. Results and Discussion: We did not detect any foodborne pathogens from harvested tomatoes in 2020 and 2021. One non-O157 STEC positive soil sample (0.1%, 1/824) was detected in the fallow treatment, and one L. monocytogenes-positive (1.1%, 1/92) was detected from the post-graze fecal samples. When assessing proportions of generic E. coli positive and counts of generic E. coli in the soil samples using mixed effect zero-inflated negative binomial models, soil samples collected in the graze cover crop treatment plot showed significant increases in the counts of generic E. coli until 61–82 days post grazing, but no difference was observed after 96–123 days, compared to the baseline of the fallow treatment. Findings from generic E. coli counts support the use of the United States Department of Agriculture (USDA) National Organic Program (NOP) 90- or 120-day interval rule between applying raw manure and harvesting in organic farming into ICLS. Additionally, we confirmed that commercial organic compost application before cover crop seeding in the winter had no significant effect on the proportions and counts of generic E. coli in the soil of the following growing seasons. This longitudinal field trial confirmed that the effect of sheep grazing on foodborne pathogen contamination in ICLS is minimal but further studies comparing the genetic associations between fecal and soil samples would be necessary to distinguish the source of foodborne pathogen contamination.

Multiple Salmonella enterica serovars and strains have been reported to be able to persist inside the foliar tissue of lettuce (Lactuca sativa L.), potentially resisting washing steps and reaching the consumer. Intraspecies variation of the bacterial pathogen and of the plant host can both significantly affect the outcome of foliar colonization. However, current understanding of the mechanisms underlying this phenomenon is still very limited. In this study, we evaluated the foliar fitness of 14 genetically barcoded S. enterica isolates from 10 different serovars, collected from plant and animal sources. The S. enterica isolates were vacuum-infiltrated individually or in pools into the leaves of three- to four-week-old lettuce plants. To estimate the survival capacity of individual isolates, we enumerated the bacterial populations at 0- and 10- days post-inoculation (DPI) and calculated their net growth. The competition of isolates in the lettuce apoplast was assessed through the determination of the relative abundance change of barcode counts of each isolate within pools during the 10 DPI experimental period. Isolates exhibiting varying apoplast fitness phenotypes were used to evaluate their capacity to grow in metabolites extracted from the lettuce apoplast and to elicit the reactive oxygen species burst immune response. Our study revealed that strains of S. enterica can substantially differ in their ability to survive and compete in a co-inhabited lettuce leaf apoplast. The differential foliar fitness observed among these S. enterica isolates might be explained, in part, by their ability to utilize nutrients available in the apoplast and to evade plant immune responses in this niche.

Leafy vegetables are among the potential foods that can combat food insecurity in developing countries. Their major drawback is a short shelf life, which limits their supply chain and is commonly associated with their high metabolic activities. Leafy vegetables have a high water content, which determines their freshness. Moisture loss through respiration and transpiration at postharvest storage is one quality attribute that leads to rapid quality deterioration. Little has been carried out in studying the mechanisms associated with the quality deterioration of leafy vegetables; however, understanding these mechanisms may aid in developing effective preservation measures. Furthermore, recent literature reviews that focus on discussing the mechanisms that lead to quality loss in leafy vegetables are scarce. The current paper aims to review the physiological and biochemical processes associated with quality deterioration in leafy vegetables. The respiration, ethylene production, moisture loss, colour, and texture are highly associated with the quality deterioration of fresh produce and, thus will be discussed critically in selected leafy vegetables, namely: broccoli and Swiss chard. The findings from this review indicate that the quality deterioration in leafy vegetables is primarily enzymatic. Understanding the mechanisms of quality deterioration involves identifying the specific enzymes responsible for each metabolic process and examining the internal and external factors that influence enzyme activities. [ABSTRACT FROM AUTHOR]

This study targets a fresh produce supply chain that includes a retailer owning private demand information, a supplier who may adopt blockchain, and a 3PL (Third Party Logistics) engaging in freshness keeping. By developing a multi‐stage game model, we study the blockchain adoption strategy and the information‐sharing strategy considering information transmission between the 3PL and the supplier and analyze the interaction of these strategies. We find that under the case of moderate blockchain cost, the retailer could encourage the supplier to adopt blockchain by sharing information strategically. In that case, the retailer would actively share with the supplier and the 3PL for fresh produce with low freshness sensitivity and serious consumer distrust. Otherwise, due to the dominant impact of information transmission, the retailer has to keep private information if consumers are less concerned about freshness, while it has to share information if consumers are more concerned about freshness. [ABSTRACT FROM AUTHOR]

The European Union (EU) regulations mandate 10% of all food packaging to be reusable by 2030. United States (U.S.) exporters of specialty crops face new challenges in ensuring microbiological food safety using reusable packaging. A novel antimicrobial formulation consisting of ammonium carboxylate salt of capric acid and L-arginine (GS-2) was recently developed as a spray coating chemical for food packaging materials. In this study, we evaluated the antimicrobial efficacy of GS-2 against microbial strains representing three foodborne bacterial pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica), one fungal spoilage organism (Aspergillus niger), and one surrogate viral pathogen (murine norovirus) on three reusable plastic materials (acrylonitrile butadiene styrene, high-density polyethylene, and polypropylene) and one cardboard packaging material, respectively. Different chemical concentrations, exposure times, and storage conditions were individually evaluated for the relative antimicrobial efficacies of GS-2 against these microorganisms. Our results showed that GS-2 was highly effective for inactivating bacterial pathogens on both plastic and cardboard surfaces. For instance, 3% GS-2 achieved a >5 log CFU/in2 reduction in E. coli O157:H7, L. monocytogenes, and S. enterica on tested plastic surfaces at an exposure time of 60 min. However, its efficacy against A. niger and murine norovirus was less optimal, resulting in a ≤1 log CFU/in2 reduction on all tested surfaces. Based on our study, GS-2 demonstrated a strong potential as an antibacterial coating reagent for reusable food packaging materials to minimize pathogen contamination and ensure the safety of the specialty crops. [ABSTRACT FROM AUTHOR]

Fresh produce prone to microbial contamination is a potential reservoir for antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs), posing challenges to food safety and public health. This systematic review aims to comprehensively assess the prevalence of bacterial pathogens and the incidence of ARB/ARGs in fresh produce and agro-ecosystems across South Asia. Twenty-two relevant studies published between 2012 and 2022 from three major scientific databases and the grey literature were identified. The results revealed a wide occurrence of microbial contamination in various types of fresh produce across South Asia, with a predominance of E. coli (16/22), Salmonella spp. (13/22), Staphylococcus spp. (5/22), and Klebsiella spp. (4/22). The agro-ecosystem serves as a complex interface for microbial interactions; studies have reported the prevalence of E. coli (1/4), Salmonella spp. (1/4) and Listeria monocytogenes (1/4) in farm environment samples. A concerning prevalence of ARB has been reported, with resistance to multiple classes of antibiotics. The presence of ARGs in fresh produce underscores the potential for gene transfer and the emergence of resistant pathogens. To conclude, our review provides insights into the requirements of enhanced surveillance, collaborative efforts, implementation of good agricultural practices, and public awareness for food safety and safeguarding public health in the region. [ABSTRACT FROM AUTHOR]

Fresh produce is suggested to contribute highly to shaping the gut resistome. We investigated the impact of pig manure and irrigation water quality on microbiome and resistome of field-grown lettuce over an entire growth period. Lettuce was grown under four regimes, combining soil amendment with manure (with/without) with sprinkler irrigation using river water with an upstream wastewater input, disinfected by UV (with/without). Lettuce leaves, soil, and water samples were collected weekly and analysed by bacterial cultivation, 16S rRNA gene amplicon sequencing, and shotgun metagenomics from total community DNA. Cultivation yielded only few clinically relevant antibiotic-resistant bacteria (ARB), but numbers of ARB on lettuce increased over time, while no treatment-dependent changes were observed. Microbiome analysis confirmed a temporal trend. Antibiotic resistance genes (ARGs) unique to lettuce and water included multidrug and β-lactam ARGs, whereas lettuce and soil uniquely shared mainly glycopeptide and tetracycline ARGs. Surface water carried clinically relevant ARB (e.g. ESBL-producing Escherichia coli or Serratia fonticola) without affecting the overall lettuce resistome significantly. Resistance markers including biocide and metal resistance were increased in lettuce grown with manure, especially young lettuce (increased soil contact). Overall, while all investigated environments had their share as sources of the lettuce resistome, manure was the main source especially on young plants. We therefore suggest minimizing soil–vegetable contact to minimize resistance markers on fresh produce. [ABSTRACT FROM AUTHOR]

Different refund policies offered by e-commerce platforms provide diverse options for consumers and are crucial for enhancing after-sales service. This study constructs a refund and ordering decision model based on three typical refund policies: both basic refund and refund guarantee option ('Policy I'), basic refund only ('Policy II'), and refund guarantee option only ('Policy III'). We examine scenarios where demand is influenced by price, refund policies, and stochastic factors, and returns are affected by refund policies, aiming to determine the optimal refund and ordering decisions for fresh produce e-commerce platforms. Our results indicate that, under the same parameters, the platform achieves the maximum order quantity and highest expected profit with Policy I. The return rate under Policy I is always higher than under Policy III, but not consistently higher than under Policy II. Additionally, as the sensitivity of demand to the refund policy increases, both the order quantity and basic refund price rise, while the refund guarantee option price decreases. Conversely, as the sensitivity of returns to the refund policy increases, the opposite occurs. Although market demand uncertainty does not impact the basic refund or refund guarantee option prices, the platform must increase order quantities to manage market volatility. [ABSTRACT FROM AUTHOR]

This paper considers an e‐tailing supply chain for fresh produce (E‐FSC) composed of a supplier investing in freshness‐keeping effort and an e‐retailer providing value‐added service. We study the e‐retailer's information sharing strategy with supplier encroachment. First, we discuss the supplier's encroachment strategy without or with information sharing and indicate that the e‐retailer may profit more from encroachment. Second, we explore the e‐retailer's information sharing strategy under two scenarios. Under the independent scenario, the e‐retailer may share information when the freshness sensitivity is comparatively high, which cannot affect the supplier's encroachment strategy. Under the interactive scenario, the e‐retailer influences the supplier's encroachment strategy through an information sharing strategy. The e‐retailer may share (withhold) information to induce (deter) encroachment when the competition intensity is comparatively low or high (moderate). Finally, we discuss the influence of the entry cost on E‐FSC members' profits, which finds that increasing entry cost may improve the supplier's profit. [ABSTRACT FROM AUTHOR]

Decentralized supply chain operation in India adds to inefficiency in management and control difficulties for perishable product supply chain (PPSC). One of the important categories of factors that underly the problem in supply chain is the establishment of processing units that results in end – product distribution. This paper presents an optimal establishment of processing unit around production area for apple supply chain as a case study of India. This study proposed amalgamation of mixed integer linear programming (MILP) and colored petri nets (CPN) to model the PPSC. The mathematical model was set up in regard with capacity of processing unit and transportation cost with continuation in partner selection using MILP approach. The simulation model directs the maximization of system performance by running in CPN environment. The values of the results are subjected to transportation cost and production area with estimate of 25% loss during post harvesting such as transportation and environmental variation. The results corresponding to the case study provided an optimal establishment of processing units. Further, the specific partner associated with the facility and transportation cost. Decision-makers can identify the set of partners from the set of facilities dependent upon the transportation cost for further supply of product using a threshold values. Thereby, the model can be used as a decision-making system for processing companies to result in efficient PPSC management. The developed model was tested and validated on case study to demonstrate our approach's applicability. [ABSTRACT FROM AUTHOR]

Contamination of leafy greens with Staphylococcus spp. can occur at various supply chain stages, from farm to table. This study comprehensively analyzes the species diversity, antimicrobial resistance, and virulence factors of Staphylococci in salad vegetables from markets in the United Arab Emirates (UAE). A total of 343 salad items were sampled from three major cities in the UAE from May 2022 to February 2023 and tested for the presence of Staphylococcus spp. using standard culture-based methods. Species-level identification was achieved using matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antimicrobial susceptibility testing was conducted using the VITEK-2 system with AST-P592 cards. Additionally, whole genome sequencing (WGS) of ten selected isolates was performed to characterize antimicrobial resistance determinants and toxin-related virulence factors. Nine Staphylococcus species were identified in 37.6% (129/343) of the tested salad items, with coagulase-negative staphylococci (CoNS) dominating (87.6% [113/129]) and S. xylosus being the most prevalent (89.4% [101/113]). S. aureus was found in 4.6% (14/343) of the salad samples, averaging 1.7 log10 CFU/g. One isolate was confirmed as methicillin-resistant S. aureus, harboring the mecA gene. It belonged to multi-locus sequence type ST-672 and spa type t384 and was isolated from imported fresh dill. Among the characterized S. xylosus (n = 45), 13.3% tested positive in the cefoxitin screen test, and 6.6% were non-susceptible to oxacillin. WGS analysis revealed that the cytolysin gene (cylR2) was the only toxin-associated factor found in S. xylosus, while a methicillin-sensitive S. aureus isolate harbored the Panton-Valentine Leukocidin (LukSF/PVL) gene. This research is the first to document the presence of methicillin-resistant S. aureus in the UAE food chain. Furthermore, S. xylosus (a coagulase-negative staphylococcus not commonly screened in food) has demonstrated phenotypic resistance to clinically relevant antimicrobials. This underscores the need for vigilant monitoring of antimicrobial resistance in bacterial contaminants, whether pathogenic or commensal, at the human-food interface. [ABSTRACT FROM AUTHOR]

Enteropathogenic bacteria, such as Salmonella, have been linked to numerous fresh produce outbreaks, posing a significant public health threat. The ability of Salmonella to persist on fresh produce for extended periods is partly attributed to its capacity to form biofilms, which pose a challenge to food decontamination and can increase pathogenic bacterial load in the food chain. Preventing Salmonella colonization of food products and food processing environments is crucial for reducing the incidence of foodborne outbreaks. Understanding the mechanisms of establishment on fresh produce will inform the development of decontamination approaches. We used Transposon-Directed Insertion site Sequencing (TraDIS-Xpress) to investigate the mechanisms used by Salmonella enterica serovar Typhimurium to colonize and establish on fresh produce over time. We established an alfalfa colonization model and compared the findings to those obtained from glass surfaces. Our research ident ified distinct mechanisms required for Salmonella establishment on alfalfa compared with glass surfaces over time. These include the type III secretion system (sirC), Fe-S cluster assembly (iscA), curcumin degradation (curA), and copper tolerance (cueR). Shared pathways across surfaces included NADH hydrogenase synthesis (nuoA and nuoB), fimbrial regulation (fimA and fimZ), stress response (rpoS), LPS O-antigen synthesis (rfbJ), iron acquisition (ybaN), and ethanolamine utilization (eutT and eutQ). Notably, flagellum biosynthesis differentially impacted the colonization of biotic and abiotic environments over time. Understanding the genetic underpinnings of Salmonella establishment on both biotic and abiotic surfaces over time offers valuable insights that can inform the development of targeted antibacterial therapeutics, ultimately enhancing food safety throughout the food processing chain. [ABSTRACT FROM AUTHOR]

The effect of plasma-activated water (PAW) generated with a dielectric barrier discharge diffusor (DBDD) system on microbial load and organoleptic quality of cucamelons was investigated and compared to the established sanitizer, sodium hypochlorite (NaOCl). Pathogenic serotypes of Escherichia coli, Salmonella enterica, and Listeria monocytogenes were inoculated onto the surface of cucamelons (6.5 log CFU g-1) and into the wash water (6 log CFU mL-1). PAW treatment involved 2 min in situ with water activated at 1,500 Hz and 120 V and air as the feed gas; NaOCl treatment was a wash with 100 ppm total chlorine; control treatment was a wash with tap water. PAW treatment produced a 3-log CFU g-1 reduction of pathogens on the cucamelon surface without negatively impacting quality or shelf life. NaOCl treatment reduced the pathogenic bacteria on the cucamelon surface by 3 to 4 log CFU g-1; however, this treatment also reduced fruit shelf life and quality. Both systems reduced 6-log CFU mL-1 pathogens in the wash water to below detectable limits. The critical role of superoxide anion radical (·O2-) in the antimicrobial power of DBDD-PAW was demonstrated through a Tiron scavenger assay, and chemistry modeling confirmed that ·O2- generation readily occurs in DBDD-PAW generated with the employed settings. Modeling of the physical forces produced during plasma treatment showed that bacteria likely experience strong local electric fields and polarization. We hypothesize that these physical effects synergize with reactive chemical species to produce the acute antimicrobial activity seen with the in situ PAW system. IMPORTANCE Plasma-activated water (PAW) is an emerging sanitizer in the fresh food industry, where food safety must be achieved without a thermal kill step. Here, we demonstrate PAW generated in situ to be a competitive sanitizer technology, providing a significant reduction of pathogenic and spoilage microorganisms while maintaining the quality and shelf life of the produce item. Our experimental results are supported by modeling of the plasma chemistry and applied physical forces, which show that the system can generate highly reactive ·O2- and strong electric fields that combine to produce potent antimicrobial power. In situ PAW has promise in industrial applications as it requires only low power (12 W), tap water, and air. Moreover, it does not produce toxic by-products or hazardous effluent waste, making it a sustainable solution for fresh food safety.

The increased consumption of fresh produce in the last decades has led to an escalation in the number of associated foodborne outbreaks. Various stressful conditions along the fresh produce supply chain can induce bacteria to enter a dormancy state, such as the persistence state and the viable but nonculturable (VBNC) state. Bacteria can develop an increased tolerance to a range of environmental stresses in the dormancy state and return to their normal growing state when conditions become favorable, leading to foodborne illnesses. This review will explore how bacteria contaminate fresh produce along the supply chain and the conditions that can promote the formation of dormant cells. Additionally, various options for detecting and eradicating dormant bacterial cells in the fresh produce supply chain will be discussed.

The COVID-19 pandemic worsened food insecurity by curbing the food supply chain, slowing the delivery of provisions to food banks and pantries, and magnifying the impact of the pandemic on those depending on such resources to meet their nutritional needs. The study’s objective was to identify areas of resilience and vulnerability in food security intervention programming during the COVID-19 crisis, with specific attention to fresh produce donation partnerships. This study examined the cultivation and provision of fresh produce to food pantries in Iowa before and during the pandemic. It also analyzed the experiences of volunteers in a Master Gardener volunteer program in Iowa, which grew the donated produce. The study analyzes program data on donation quantities and labor hours and uses a time series analysis and content analysis to understand changes between the pre-pandemic and pandemic years. Findings include a significant decrease in labor hours during the pandemic years of 2020–2021, which volunteers attributed to multi­­level government policies and social distancing requirements. Vulnerabilities revealed in this study were exacerbated by the pandemic rather than singly caused by it. Volunteer shortages, donation inconsistency, and exclusionary practices of community appeared to be inherent to the concept and structure of volunteer-based food donation partnership programs.

ABSTRACT In this study, the genomes of 22 Enterobacteriaceae isolates from fresh produce and herbs obtained from retail markets in northern Germany were completely sequenced with MiSeq short-read and MinION long-read sequencing and assembled using a Unicycler hybrid assembly. The data showed that 17 of the strains harbored between one and five plasmids, whereas in five strains, only the circular chromosomal DNA was detected. In total, 38 plasmids were identified. The size of the plasmids detected varied between ca. 2,000 and 326,000 bp, and heavy metal resistance genes were found on seven (18.4%) of the plasmids. Eleven plasmids (28.9%) showed the presence of antibiotic resistance genes. Among large plasmids (>32,000 bp), IncF plasmids (specifically, IncFIB and IncFII) were the most abundant replicon types, while all small plasmids were Col-replicons. Six plasmids harbored unit and composite transposons carrying antibiotic resistance genes, with IS26 identified as the primary insertion sequence. Class 1 integrons carrying antibiotic resistance genes were also detected on chromosomes of two Citrobacter isolates and on four plasmids. Mob-suite analysis revealed that 36.8% of plasmids in this study were found to be conjugative, while 28.9% were identified as mobilizable. Overall, our study showed that Enterobacteriaceae from fresh produce possess antibiotic resistance genes on both chromosome and plasmid, some of which are considered to be transferable. This indicates the potential for Enterobacteriaceae from fresh produce that is usually eaten in the raw state to contribute to the transfer of resistance genes to bacteria of the human gastrointestinal system.IMPORTANCEThis study showed that Enterobacteriaceae from raw vegetables carried plasmids ranging in size from 2,715 to 326,286 bp, of which about less than one-third carried antibiotic resistance genes encoding resistance toward antibiotics such as tetracyclines, aminoglycosides, fosfomycins, sulfonamides, quinolones, and β-lactam antibiotics. Some strains encoded multiple resistances, and some encoded extended-spectrum β-lactamases. The study highlights the potential of produce, which may be eaten raw, as a potential vehicle for the transfer of antibiotic-resistant bacteria.

Farmers markets offer an apparently easy way for small-scale or hobbyist food producers to sell fresh produce, meat, and poultry from their farms or dis­tribute value-added products, but they may be unaware of the foodborne illness risks associated with both fresh produce and derivative products, as well as of their local food safety requirements. Food guidance and rules vary from state to state and market to market, making it difficult for indi­viduals to navigate the various regulatory levels. Even if a local food producer is exempt from these rules due to their amount of sales, they will still benefit greatly from resources and educational tools that increase awareness and knowledge of food safety best practices. This review discusses current knowledge of and guidelines for food safety in farmers markets based on peer-reviewed and grey literature as well as published guidelines and recommendations. We examine facilities and supplies, regulatory measures, education and train­ing, and Good Farmers Market Practices as pre­ventive measures to enhance food safety in farmers markets, which are critical to local and regional food systems. Overall, we identified various barri­ers to implementing farmers market food safety standards and practices in this scoping review; removing these barriers will require the participa­tion of local regularity authorities, market managers, vendors, and consumers.

Human noroviruses pose grave threats to public health and economy. In this study, we genetically engineered yeast (Saccharomyces cerevisiae EBY100) to display specific norovirus-binding nanobodies (Nano-26 and Nano-85) on cell surface to facilitate the concentration of noroviruses for improved detection. Binding of norovirus virus-like particles (VLPs) to these nanobody-displaying yeasts was confirmed and characterized using confocal microscopy and flow cytometry. The ability of our engineered yeasts to capture norovirus VLPs can reach up to 91.3%. Furthermore, this approach was applied to concentrate and detect norovirus VLPs in a real food matrix. A wide linear detection range (1-104 pg/g) was observed, and the detection limit on spiked spinach was calculated as low as 0.071 pg/g. Overall, our engineered yeasts could be a promising approach to concentrate and purify noroviruses in food samples for easy detection, which allows us to prevent the spread of food-borne virus in the food supply chain.

Over the last thirty years, the presence of Salmonella spp. on cantaloupes has been linked to multiple large and deadly foodborne outbreaks in multiple countries. To identify factors associated with the number of cases and risk of severe illness in these outbreaks, information from previous melon-associated salmonellosis outbreaks was analyzed. Data were collected from sixty outbreak investigations. Compared to other melon types, such as watermelon, honeydew, and Galia melon, cantaloupes had the highest public health burden. Cantaloupes were implicated in 43% of reported melon-related outbreaks, 51% of melon-related laboratory-confirmed cases, 54% of melon-related hospitalizations, and 76% of melon-related deaths. In the United States, imported cantaloupes were associated with higher rates of severe salmonellosis and a greater diversity of Salmonella spp. serovars compared to domestically grown cantaloupes. Cantaloupes implicated in outbreaks were equally likely to have been consumed in either private or public settings. Larger outbreaks were associated with the consumption of precut cantaloupe and/or the consumption of cantaloupes in public settings. With the identification of these contributing factors, a literature search was conducted to assess the state of knowledge concerning Salmonella and cantaloupes. Several gaps in the literature were noted and are discussed in the context of reducing the number of illnesses associated with the presence of Salmonella on cantaloupes.

Introduction: Biological soil amendments of animal origin (BSAAO), including untreated amendments are often used to improve soil fertility and are particularly important in organic agriculture. However, application of untreated manure on cropland can potentially introduce foodborne pathogens into the soil and onto produce. Certified organic farms follow the USDA National Organic Program (NOP) standards that stipulate a 90- or 120-day interval between application of untreated manure and crop harvest, depending on whether the edible portion of the crop directly contacts the soil. This time-interval metric is based on environmental factors and does not consider a multitude of factors that might affect the survival of the main pathogens of concern. The objective of this study was to assess predictors for the prevalence of Shiga-toxin-producing Escherichia coli (non-O157 STEC) in soils amended with untreated manure on USDA-NOP certified farms. Methods: A longitudinal, multi-regional study was conducted on 19 farms in four USA regions for two growing seasons (2017–2018). Untreated manure (cattle, horse, and poultry), soil, and irrigation water samples were collected and enrichment cultured for non-O157 STEC. Mixed effects logistic regression models were used to analyze the predictors of non-O157 STEC in the soil up to 180 days post-manure application. Results and discussion: Results show that farm management practices (previous use with livestock, presence of animal feces on the field, season of manure application) and soil characteristics (presence of generic E. coli in the soil, soil moisture, sodium) increased the odds of STEC-positive soil samples. Manure application method and snowfall decreased the odds of detecting STEC in the soil. Time-variant predictors (year and sampling day) affected the presence of STEC. This study shows that a single metric, such as the time interval between application of untreated manure and crop harvest, may not be sufficient to reduce the food safety risks from untreated manure, and additional environmental and farm-management practices should also be considered. These findings are of particular importance because they provide multi-regional baseline data relating to current NOP wait-time standards. They can therefore contribute to the development of strategies to reduce pathogen persistence that may contribute to contamination of fresh produce typically eaten raw from NOP-certified farms using untreated manure.

Low level of rifampicin‐resistant E. coli is frequently used in food safety research as a model microorganism and is typically enumerated using traditional Most Probable Number (MPN) method. To simplify the process, we developed and validated a modified MPN method based on lactose peptone broth (LPB) containing rifampicin and bromocresol purple, the broth changes to a yellow color due to pH shifts induced by lactose fermentation from E. coli. E. coli TVS353 were prepared in following suspensions including healthy cells, injured cells, competitive bacteria with or without rifampicin resistance, and unknown natural microflora. E. coli TVS353 was quantified by traditional MPN method and our improved method. At a predicted level of 1 log CFU/mL, there was no significant difference in the MPN index of LPBR compared with TSB and TSBR in these suspensions (p > 0.05). Confirmation results generated from this new color change MPN method were analogous to traditional MPN methods. [ABSTRACT FROM AUTHOR]

The scope of this study was to enhance the shelf life of green bell peppers via application of rice starch based edible coating incorporated with onion peel extract (OPE). The physicochemical properties of uncoated (control) and coated bell peppers were evaluated at different intervals during storage at refrigeration temperature (4 ± 0.5°C) for 15 days. The results indicated that rice starch based edible coating considerably decreased the physiological weight loss while maintaining titratable acidity, total soluble solids, and pH of stored bell peppers. The coated bell peppers also had higher total phenolic content, total flavonoid content, and antioxidant activity when compared with control. The texture analysis after 15 days revealed that the coated samples were firmer (4.77 N) than the control (2.95 N). Also, the treated bell peppers received better sensory scores in terms of freshness, color, taste, and hardness leading to higher overall acceptability (5.2) in comparison to control sample (1.0). Consequently, the findings of this study suggested that preservation of green bell peppers with OPE enriched rice starchbased coating could delay the senescence process leading to their reduced postharvest loss. [ABSTRACT FROM AUTHOR]

Considering the characteristics of both quality and quantity losses in fresh produce as well as the existence of spot markets, optimal retailer ordering, pricing, and freshness-keeping decisions through the single ordering policy (firm ordering only or option ordering only) and the mixed ordering policy (firm ordering and option ordering simultaneously) are constructed based on option contracts and analyzed for the retailer under different ordering policies. The results show that there is a unique optimal pricing, ordering, and freshness-keeping decision under all three ordering policies, but there is no joint decision. The optimal freshness-keeping and retail price under the mixed ordering policy are lower than those under the option ordering only but higher than those under the firm ordering only. When only a single order can be placed, the retailer's optimal ordering policy is determined by demand risk. When all three ordering policies are available, the optimal ordering policy for the retailer is the mixed ordering policy. A spot market will weaken the role of option contracts in mitigating supply chain risks, and the larger the risk, the more significant the role of the spot market. [ABSTRACT FROM AUTHOR]

With the construction of a multi-period newsvendor model, this study examines the ordering behaviour and pricing decisions of a fresh produce firm. The firm ordered the fresh produce via a wholesale price contract and option contract to determine the optimal preliminary order quantity, option order quantity, and retail pricing when faced with price-dependent random demand. We first determine the optimal decision that could be made through the use of the single-period model. The results revealed that the firm's retail price, option order quantity and total order quantity all increased in the circulation loss rate. In contrast, the preliminary order quantity was found to decrease in the circulation loss rate. In the multi-period model, the retail price and total order quantity were unaffected by the price difference between the regular and concessionary prices, while an increase in the price difference caused an increase in the option order quantity and decrease in the preliminary order quantity in the previous period. Further, a lower discount factor for the concessionary price than for the regular price did not have as much of an effect on the retail price and total order quantity, while a rise in the discount factor led to a fall in the option order quantity as well as a rise in the preliminary order quantity in the previous period. [ABSTRACT FROM AUTHOR]

Contamination of fresh produce with Listeria monocytogenes can occur throughout the supply chain, including at retail, where Listeria spp., including L. monocytogenes, may be introduced and spread via various routes. However, limited tools are available for retailers to assess practices that can enhance control of Listeria transmission to fresh produce. Therefore, we developed an agent-based model that can simulate Listeria transmission in retail produce sections to optimize environmental sampling programs and evaluate control strategies. A single retail store was used as a model environment, in which various routes of Listeria introduction into and transmission between environmental surfaces were modeled. Model prediction (i.e., Listeria prevalence) was validated using a published longitudinal study for all surfaces that were included in both the model and the validation data. Sensitivity analysis using the Partial Rank Correlation Coefficient showed that (i) initial Listeria concentration from incoming produce, (ii) transfer coefficient from produce to employee’s hands, and (iii) transfer coefficient from consumer to produce were the top three parameters that were significantly (p

The demand for fresh produce is rising daily as it's an excellent way to maintain a healthy lifestyle. The current work fixed the target employing culture-based and molecular techniques for isolating and identifying the pathogenic Vibrio parahaemolyticus from fresh produce. The colonial appearance on TCBS agar and CHROMagar culture plates revealed the prevalence of Vibrio spp. and V. parahaemolyticus in all examined samples, which were 45/112 (40.2%) and 40/112 (35.7%), with the highest load of up to 2.0x105cfu/g and 6.4x103cfu/g, respectively. Sixty isolates in all were chosen for further molecular characterization. Multiplex PCR results exhibited that all tested isolates were positive for tlh gene and six for tdh gene but none of isolate for trh gene. According to obtained data on antimicrobial susceptibility, the major portion of tested strains was found to be resistant to ampicillin (90%), tetracycline (80%), and streptomycin (70%). The range of the multiple antibiotic index was 0-0.33. This study finding revealed that the existence of potential pathogenic V. parahaemolyticus in tested fresh produce samples constitutes a risk to public health and consumer safety thus urging continued surveillance. [ J Adv Biotechnol Exp Ther 2024; 7(2.000): 303-313]

COVID-19 is a major public health emergency, the Chinese government adopts pandemic prevention and control measures such as home quarantine in order to block the strong contagiousness of the virus. In order to solve the problem of distribution difficulties due to the limited transportation resources brought by the pandemic and to guarantee the demand of fresh agricultural products for the isolated residents, this study takes the emergency supply as the main objective, and designs three distribution modes, namely, single distribution center, multi-vehicle model based on the classification of temperature zones, and multi-distribution center for isolated communities of different sizes, with the objectives of minimizing the number of vehicles in use, minimizing the average response time, and minimizing the risk of viral infections. A multi-objective optimization model was constructed as the objectives. Then the genetic algorithm is improved by adding destruction operator, repair operator and greedy operation, and the effectiveness of the algorithm is verified through empirical research, and the advantages of the algorithm in convergence speed are compared and analyzed. Finally, different distribution methods are suggested for the number of communities of different sizes. This study can provide a scientific basis for government departments to formulate an optimized decision-making plan for the emergency supply and distribution of fresh agricultural products under public health emergencies.

Fresh produce prone to microbial contamination is a potential reservoir for antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs), posing challenges to food safety and public health. This systematic review aims to comprehensively assess the prevalence of bacterial pathogens and the incidence of ARB/ARGs in fresh produce and agro-ecosystems across South Asia. Twenty-two relevant studies published between 2012 and 2022 from three major scientific databases and the grey literature were identified. The results revealed a wide occurrence of microbial contamination in various types of fresh produce across South Asia, with a predominance of E. coli (16/22), Salmonella spp. (13/22), Staphylococcus spp. (5/22), and Klebsiella spp. (4/22). The agro-ecosystem serves as a complex interface for microbial interactions; studies have reported the prevalence of E. coli (1/4), Salmonella spp. (1/4) and Listeria monocytogenes (1/4) in farm environment samples. A concerning prevalence of ARB has been reported, with resistance to multiple classes of antibiotics. The presence of ARGs in fresh produce underscores the potential for gene transfer and the emergence of resistant pathogens. To conclude, our review provides insights into the requirements of enhanced surveillance, collaborative efforts, implementation of good agricultural practices, and public awareness for food safety and safeguarding public health in the region.

Leafy vegetables are among the potential foods that can combat food insecurity in developing countries. Their major drawback is a short shelf life, which limits their supply chain and is commonly associated with their high metabolic activities. Leafy vegetables have a high water content, which determines their freshness. Moisture loss through respiration and transpiration at postharvest storage is one quality attribute that leads to rapid quality deterioration. Little has been carried out in studying the mechanisms associated with the quality deterioration of leafy vegetables; however, understanding these mechanisms may aid in developing effective preservation measures. Furthermore, recent literature reviews that focus on discussing the mechanisms that lead to quality loss in leafy vegetables are scarce. The current paper aims to review the physiological and biochemical processes associated with quality deterioration in leafy vegetables. The respiration, ethylene production, moisture loss, colour, and texture are highly associated with the quality deterioration of fresh produce and, thus will be discussed critically in selected leafy vegetables, namely: broccoli and Swiss chard. The findings from this review indicate that the quality deterioration in leafy vegetables is primarily enzymatic. Understanding the mechanisms of quality deterioration involves identifying the specific enzymes responsible for each metabolic process and examining the internal and external factors that influence enzyme activities.

Due to the immense societal and economic impact that the COVID-19 pandemic has caused, limiting the spread of SARS-CoV-2 is one of the most important priorities at this time. The global interconnectedness of the food industry makes it one of the biggest concerns for SARS-CoV-2 outbreaks. Although fomites are currently considered a low-risk route of transmission for SARS-CoV-2, new variants of the virus can potentially alter the transmission dynamics. In this study, we compared the survival rate of pseudotyped SARS-CoV-2 on plastic with some commonly used food samples (i.e., apple, strawberry, grapes, tomato, cucumber, lettuce, parsley, Brazil nut, almond, cashew, and hazelnut). The porosity level and the chemical composition of different food products affect the virus's stability and infectivity. Our results showed that tomato, cucumber, and apple offer a higher survival rate for the pseudotyped viruses. Next, we explored the effectiveness of ozone in deactivating the SARS-CoV-2 pseudotyped virus on the surface of tomato, cucumber, and apple. We found that the virus was effectively inactivated after being exposed to 15 ppm of ozone for 1 h under ambient conditions. SEM imaging revealed that while ozone exposure altered the wax layer on the surface of produce, it did not seem to damage the cells and their biological structures. The results of our study indicate that ozonated air can likely provide a convenient method of effectively disinfecting bulk food shipments that may harbour the SARS-CoV-2 virus.

Introduction: Integrated crop-livestock systems (ICLS) use animals to graze crop residues or cover crops before planting fresh produce and provide ecosystem services to support organic vegetable production. However, there is a risk of foodborne pathogen transfer to fresh produce because grazing may introduce enteric foodborne pathogens into the soil via animal feces, which may subsequently be transferred to the produce. Methods: To examine the effect of cover crop use and the risk of cover crop grazing on the contamination of soil and produce by foodborne pathogens in ICLS, a three-year (2019-2021) experimental study was conducted in organically managed plots, which were assigned three different treatments (fallow without cover crop or grazing, cover crop without grazing, or cover crop with grazing by sheep) in a maize/tomato rotation. During the three years of the experiment, a total of 184 pre- and post-graze fecal samples and 96 samples of tomatoes were collected to test for foodborne pathogens (Escherichia coli O157, non-O157 Shiga toxin-producing Escherichia coli (STEC), and Listeria (L.) monocytogenes). Soil samples were collected monthly until 126-171 days after grazing (824 in total) to examine the presence of foodborne pathogens, and generic E. coli (MPN/g) was quantified to compare its persistence among the three treatments. Results and Discussion: We did not detect any foodborne pathogens from harvested tomatoes in 2020 and 2021. One non-O157 STEC positive soil sample (0.1%, 1/824) was detected in the fallow treatment, and one L. monocytogenespositive (1.1%, 1/92) was detected from the post-graze fecal samples. When assessing proportions of generic E. coli positive and counts of generic E. coli in the soil samples using mixed effect zero-inflated negative binomial models, soil samples collected in the graze cover crop treatment plot showed significant increases in the counts of generic E. coli until 61-82 days post grazing, but no difference was observed after 96-123 days, compared to the baseline of the fallow treatment. Findings from generic E. coli counts support the use of the United States Department of Agriculture (USDA) National Organic Program (NOP) 90- or 120-day interval rule between applying raw manure and harvesting in organic farming into ICLS. Additionally, we confirmed that commercial organic compost application before cover crop seeding in the winter had no significant effect on the proportions and counts of generic E. coli in the soil of the following growing seasons. This longitudinal field trial confirmed that the effect of sheep grazing on foodborne pathogen contamination in ICLS is minimal but further studies comparing the genetic associations between fecal and soil samples would be necessary to distinguish the source of foodborne pathogen contamination. [ABSTRACT FROM AUTHOR]

This paper considers a fresh produce supply chain in which a retailer sources alternative produce from two competing suppliers. The suppliers make efforts to preserve product freshness, while the retailer, with demand forecast information, can share it with none, one or both of the suppliers strategically. By constructing a multistage game model, the optimal demand information sharing strategy in the supply chain is explored. The results show that the retailer has the willingness to disclose demand information only when the freshness elasticity is high. Significantly, with the improvement of the freshness elasticity, the retailer will transform from sharing information with both suppliers to one supplier. The suppliers are always willing to accept the information disclosed by the retailer. However, complete transparency of demand information may hurt the supply chain under certain conditions. To improve the supply chain performance, the retailer can charge both suppliers for information fees and adjust from sharing information with no suppliers to both suppliers with a relatively low freshness elasticity. Conversely, the retailer can change from sharing information with both suppliers to sharing information with one supplier through a charging contract with a relatively high freshness elasticity. [ABSTRACT FROM AUTHOR]

Low‐income households and minority communities in the US are considered highly vulnerable to diet‐and nutrition‐related adverse health effects. Households' food‐related decisions may entail real or perceived tradeoffs among price, preference, access and availability, and other factors. We use a sample of low‐income households, mostly from African American communities, from the Nashville metropolitan area of Tennessee to assess fruit and vegetable purchasing behavior. We found that the vast majority of household shops for fruits and vegetables (F&Vs) less than two to three times per month. Using probit and nested logit models, we analyzed purchase decisions and investigated reasons and factors determining "not to buy" F&Vs by low‐income households. [ABSTRACT FROM AUTHOR]

Green nanotechnology is fast growing in feasible precision agriculture that assures to refashion food production. This work presents the silver (Ag) and zinc oxide (ZnO) nanoparticles (NPs) synthesized by the green synthesis method. The morphology, composition, structure, size, and purity have been confirmed by and characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, and photoluminescence (PL). The optical energy band gap for Ag and ZnO NPs was 2.5 eV and 3.5 eV respectively as investigated by UV–visible spectroscopy. The primary goal of this study is to develop eco-friendly biosynthesized nanoparticles that enhance the shelf time of fruits at room temperature. For this purpose, the different concentrations of Ag and ZnO nanostructures (100 ppm, 500 ppm, and 1000 ppm) have been applied to apples and lemons to study the influence on their shelf life. The PWL% and PO are employed by using a 5-point scale to calculate shelf time correctly. Moreover, periodic measurements have been performed over the coated apple and lemon samples to understand the chemistry and physics behind improvements in shelf life. In contrast to Ag NPs, ZnO NPs present low weight loss at 100 ppm and 1000 ppm. The weight loss percentage of lemon showed direct relation with a concentration of ZnO NPs, whereas inverse for the case of Ag NPs due to strong pathogenic effects of ZnO NPs. These nanoparticles can be easily synthesized by using freely available neem leaves and highly useful for the agricultural industry and food sectors around the globe. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to determine the prevalence and virulome of Listeria in fresh produce distributed in urban communities. Methods: A total of 432 fresh produce samples were collected from farmer's markets in Michigan and West Virginia, USA, resulting in 109 pooled samples. Listeria spp. were isolated and L. monocytogenes was subjected to genoserogrouping by PCR and genotyping by pulsed-field gel electrophoresis (PFGE). Multi-locus sequence typing (MLST) and core-genome multi-locus sequence typing (cgMLST) were conducted for clonal identification. Results: Forty-eight of 109 samples (44.0%) were contaminated with Listeria spp. L. monocytogenes serotype 1/2a and 4b were recovered from radishes, potatoes, and romaine lettuce. Four clonal complexes (CC) were identified and included hypervirulent CC1 (ST1) and CC4 (ST219) of lineage I as well as CC7 (ST7) and CC11 (ST451) of lineage II. Clones CC4 and CC7 were present in the same romaine lettuce sample. CC1 carried Listeria pathogenicity island LIPI-1 and LIPI-3 whereas CC4 contained LIPI-1, LIPI-3, and LIPI-4. CC7 and CC11 had LIPI-1 only. Discussion: Due to previous implication in outbreaks, L. monocytogenes hypervirulent clones in fresh produce pose a public health concern in urban communities. [ABSTRACT FROM AUTHOR]

Food bioactive packaging has received increasing attention from consumers and the food industry for its potential to reduce food waste and environmental issues. Several materials can be used to produce edible films/coats; however, bio-based, cost-effective, and sustainable coatings have gained a high reputation these days. For instance, Aloe vera gel (AV) is a promising bio-based material for edible coatings and films; therefore, the present study aimed to investigate the film-forming abilities of AV and Chitosan (CH) combination as a potential active food packaging material. The physicochemical and mechanical characteristics of formed films of various combinations were prepared at different concentrations, i.e., CH (0.5% w/v), AV (100%), CH:AV (75:25), and CH:AV (60:40). The results showed significant differences among all the prepared edible films wherein these differences were mainly on account of incorporating AV gel. The rheological and antioxidant properties of the formulations improved with the inclusion of AV gel. The films composed of CH:AV (60:40) positively affected the water solubility, thermal properties, and water vapour permeability of the edible films. The X-ray Diffraction (XRD) and Scanning electron microscopy (SEM) results showed that the films composed of CH:AV, (60:40) were amorphous and had smooth morphology. Further, the edible film solutions were applied to fresh figs (Ficus carica) to investigate their role in preserving fruits during storage. A significant reduction in microbial growth was found in coated fruits after 28 days of cold storage. The films composed of CH and AV showed overall improved results compared to the CH (0.5%, w/v). Therefore, the used formulations (CH:AV, 60:40) can form a sustainable film that has the potential to be utilized for fresh product preservation to maintain its quality and shelf life. [ABSTRACT FROM AUTHOR]

We assessed the efficacy of oversampling techniques to enhance machine learning model performance in predicting Escherichia coli MG1655 presence in spinach wash water. Three oversampling methods were applied to balance two datasets, forming the basis for training random forest (RF), support vector machines (SVMs), and binomial logistic regression (BLR) models. Data underwent method‐specific centering and standardization, with outliers replaced by feature‐specific means in training datasets. Testing occurred without these preprocessing steps. Model hyperparameters were optimized using a subset of testing data via 10‐fold cross‐validation. Models were trained on full datasets and tested on newly acquired spinach wash water samples. Synthetic Minority Oversampling Technique (SMOTE) and Adaptive Synthetic Sampling approach (ADASYN) achieved strong results, with SMOTE RF reaching an accuracy of 90.0%, sensitivity of 93.8%, specificity of 87.5%, and an area under the curve (AUC) of 98.2% (without data preprocessing) and ADASYN achieving 86.55% accuracy, 87.5% sensitivity, 83.3% specificity, and a 92.4% AUC. SMOTE and ADASYN significantly improved (p < 0.05) SVM and RF models, compared to their non‐oversampled counterparts without preprocessing. Data preprocessing had a mixed impact, improving (p < 0.05) the accuracy and specificity of the BLR model but decreasing the accuracy and specificity (p < 0.05) of the SVM and RF models. The most influential physiochemical feature for E. coli detection in wash water was water conductivity, ranging from 7.9 to 196.2 µS. Following closely was water turbidity, ranging from 2.97 to 72.35 NTU within this study. [ABSTRACT FROM AUTHOR]

Fresh produce handling, particularly in final inspection and pack, is highly dependent on dextrous human labour. As part of a relatively low-profit margin industry, rising wage costs and labour shortages are impacting the viability of this sector and are a direct threat to global food security. Adoption of robotics is required to automate delicate handling tasks; this is a key goal for sustainable and profitable businesses that supply packed produce to consumers. This mini review considers the state of the art, as well as any developments required in robotic technology for the automation of inspection and packing of whole unprocessed fresh produce. There is a particular focus on robotic end effectors for the handling of fresh produce. We consider the role of soft robotics research in meeting hygiene and safety requirements, as well as the current limited range of end effectors for handling of highly varied and delicate produce types. Future directions are discussed based on the observation of available current technology available in research and the application to commercial practice. [ABSTRACT FROM AUTHOR]

This study analyzed the virulence, growth characteristics, and cytotoxicity of Bacillus cereus strains isolated from fresh produce, including romaine lettuce, sesame leaf, tomato, and cucumber grown by different methods. Polymerase chain reaction (PCR) was used to assess the toxigenic potential, and the cytotoxicity of B. cereus was estimated using cell-free supernatant in HEp-2 cells. The study found that hblD was the predominant diarrheal enterotoxin in the 59 isolated B. cereus strains, followed by nheB and hblC. The optimal temperatures for growth ranged from 42 to 44 °C, with the highest growth rates and shortest lag times. Cytotoxicity varied greatly depending on abiotic factors, including NaCl, pH, and medium, and was not always correlated with cell population. The study highlights the importance of establishing control measures to prevent B. cereus intoxication in fresh vegetables. [ABSTRACT FROM AUTHOR]

Food safety has emerged as a paramount concern for both Vietnamese consumers and the government. However, limited data are available on food safety management systems in Viet Nam. This study identified significant gaps in good agricultural and hygienic practices along the fresh produce chain (farmers and traditional wholesalers/market sellers) in the region of Da Nang, Viet Nam. This was achieved through a survey on good agricultural and hygienic practices for farmers (n = 100) and sellers (n = 100), which researchers further supplemented by microbiological analysis for E. coli, Salmonella spp., and Listeria monocytogenes on leafy greens, water in contact with produce and contact surfaces (hands). The results indicated that 86.0 % of farmers and 54.0 % of sellers received food safety training in the last 3 years; and women dominated both vegetable cultivation but also trading. Farm-level deficiencies included inadequate handwashing practices, lack of documentation for manure application schedules, improper washing and drying of harvest tools, failure to keep containers elevated off the ground, improper storage of vegetables, and inadequate covering of containers, with respectively 34.0 %, 30.3 %, 12.1 %, 41.7 % and 7.9 % of farmers executing the practice as prescribed by the WHO/FAO ‘5 keys of growing safer fruits and vegetables’. As for sellers, the most dominant gaps (

The use of flume tanks for tomato processing has been identified as a potential source of cross-contamination, which could result in foodborne illness. This study's objective was to assess the efficacy of peroxyacetic acid (PAA) at a concentration of ≤80 mg/L in preventing Salmonella enterica cross-contamination under various organic loads in a benchtop model tomato flume tank. The stability of 80 mg/L PAA at different chemical oxygen demand (COD) levels was also tested. Tomatoes were spot inoculated with a five-serovar rifampin-resistant (rif+) Salmonella cocktail (106 or 108 colony forming unit (CFU)/tomato). Inoculated (n = 3) and uninoculated (n = 9) tomatoes were introduced into the flume system containing 0–80 mg/L PAA and 0 or 300 mg/L COD. After washing for 30, 60, or 120 s, uninoculated tomatoes were sampled and analyzed for cross-contamination. All experiments were conducted in triplicate. Increasing the organic load (measured as COD) affected the stability of PAA in water with significantly faster dissociation when exposed to 300 mg/L COD. The concentration of PAA, inoculum level, COD levels, and time intervals were all significant factors that affected cross-contamination. Cross-contamination occurred at the high inoculum level (108 CFU/tomato) even when 80 mg/L PAA was present in the model flume tank, regardless of the organic load level. When the tomatoes were contaminated at a level of 106 CFU/tomato, concentrations as low as 5 mg/L of PAA were effective in preventing cross-contamination at 0 mg/L COD; however, 100 % tomatoes (9/9) were positive when the organic load increased to 300 mg/L COD. When the PAA concentration was increased to 10 mg/L, it effectively prevented cross-contamination in the tank, regardless of the presence of organic load. These results suggest that using PAA at concentrations below the maximum limit remains effective in limiting bacterial cross-contamination and offers a more environment-friendly option for tomato packinghouse operators.

Fresh vegetables have been linked to multiple foodborne outbreaks in the U.S., with Listeria monocytogenes and Salmonella enterica identified as leading causes. Beyond raw vegetables, cooked vegetables can also pose food safety concerns due to improper cooking temperature and time combinations or postcooking contamination. Cooked vegetables, having had their native microbiota reduced through heat inactivation, might provide an environment that favors the growth of pathogens due to diminished microbial competition. While the risks associated with raw vegetables are recognized, the survival and growth of pathogens on cooked vegetables remain inadequately studied. This study investigated the growth kinetics of both L. monocytogenes and S. enterica on various cooked vegetables (carrot, corn, onions, green bell pepper, and potato). Vegetables were cooked at 177°C until the internal temperature reached 90°C and then cooled to 5°C. Cooled vegetables were inoculated with a four-strain cocktail of either L. monocytogenes or S. enterica at 3 log CFU/g, then stored at different temperatures (5, 10, or 25°C) for up to 7 days. Both pathogens survived on all vegetables when stored at 5°C. At 10°C, both pathogens proliferated on all vegetables, with the exception of L. monocytogenes on pepper. At 25°C, the highest growth rates were observed by both pathogens on carrot (5.55 ± 0.22 and 6.42 ± 0.23 log CFU/g/d for L. monocytogenes and S. enterica, respectively). S. enterica displayed higher growth rates at 25°C compared to L. monocytogenes on all vegetables. Overall, these results bridge the knowledge gap concerning the growth kinetics of both S. enterica and L. monocytogenes on various cooked vegetables, offering insights to further enhance food safety.

[This corrects the article DOI: 10.3389/fmicb.2021.709418.].

Introduction Antimicrobial resistance (AMR) has emerged as one of the leading threats to public health. AMR possesses a multidimensional challenge that has social, economic, and environmental dimensions that encompass the food production system, influencing human and animal health. The One Health approach highlights the inextricable linkage and interdependence between the health of people, animal, agriculture, and the environment. Antibiotic use in any of these areas can potentially impact the health of others. There is a dearth of evidence on AMR from the natural environment, such as the plant-based agriculture sector. Antibiotics, antibiotic-resistant bacteria (ARB), and related AMR genes (ARGs) are assumed to present in the natural environment and disseminate resistance to fresh produce/vegetables and thus to human health upon consumption. Therefore, this study aims to investigate the role of vegetables in the spread of AMR through an agroecosystem exploration in Ahmedabad, India. Protocol The present study will be executed in Ahmedabad, located in Gujarat state in the Western part of India, by adopting a mixed-method approach. First, a systematic review will be conducted to document the prevalence of ARB and ARGs on fresh produce in South Asia. Second, agriculture farmland surveys will be used to collect the general farming practices and the data on common vegetables consumed raw by the households in Ahmedabad. Third, vegetable and soil samples will be collected from the selected agriculture farms and analyzed for the presence or absence of ARB and ARGs using standard microbiological and molecular methods. Discussion The analysis will help to understand the spread of ARB/ARGs through the agroecosystem. This is anticipated to provide an insight into the current state of ARB/ARGs contamination of fresh produce/vegetables and will assist in identifying the relevant strategies for effectively controlling and preventing the spread of AMR.