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Airborne microorganisms in food processing environments pose a potential risk for food product contamination. Yet, the absence of established standards or guidelines setting quantitative limits on airborne microorganisms underscores a critical gap in current regulatory frameworks. This review seeks to explore the feasibility of establishing quantitative limits for airborne microorganisms in food processing facilities, aiming to provide evidence-based guidance to enhance food safety practices in the industry. The review begins by addressing the complexities of microbial air quality in the food industry through a general literature search covering sources of airborne microorganisms, factors affecting particle deposition, air sampling methods and preventive measures. Subsequently, it employs a structured approach to assess the significance of air quality and its impact on product quality. Utilizing the PRISMA method, relevant scientific literature from May 2002 to May 2022 was examined, resulting in 26 articles meeting inclusion criteria from a pool of 11,737 original research papers. Additionally, the review investigates existing probability models for assessing airborne contamination to enhance air quality risk assessment in food safety management systems. The literature reveals a lack of substantial evidence supporting a direct correlation between airborne microorganisms and food contamination. The absence of standardized air sampling methodologies in previous studies hinders the comparability and reliability of research findings. Additionally, the literature fails to establish a conclusive relationship between influencing factors such as total particle counts, temperature, relative humidity and airborne contamination. Contradictory probability models for quantifying airborne contamination, and the absence of tailored preventive measures, hinder effective control and undermine microbial contamination control in diverse food processing contexts. In conclusion, the development of numeric guidelines for airborne contamination necessitates a tailored approach, considering factors such as product characteristics and production context. By integrating risk assessment models into this process, a more thorough comprehension of contamination risks can be achieved, providing tailored guidance based on the identified risk levels for each product. Ongoing collaborative efforts are essential to develop evidence-based guidelines that effectively mitigate risks without incurring unnecessary costs. • The extent of airborne contamination in the food industry remains unknown. • Quantitative data on particle deposition factors, such as airflow, is lacking. • Progress is hampered by inconsistent air sampling methods. • Probability models overlook production context and product characteristics. • Numeric guidelines need customization, integrating risk assessment models. [ABSTRACT FROM AUTHOR]

The Hazard Analysis and Critical Control Point (HACCP) system plays a crucial role in ensuring food safety within food service establishments, effectively reducing the risk of foodborne diseases. This study focused on assessing the risk of microbe contamination in poultry-based cook-served food during meal preparation in four restaurants and five selected HACCP-certified hotels in eastern China. We examined samples collected from 26 poultry-based cooked dishes, 248 food contact surfaces, 252 non-food contact surfaces, and 121 hand swabs. Our findings indicated a favorable trend of compliance with Chinese national standards, as Escherichia coli and Campylobacter were not detected in any cooked food samples. However, the microbiological assessments revealed non-compliance with total plate count standards in 7 % of the cooked samples from restaurants. In contrast, both dine-in hotels and restaurants exhibited significant non-compliance with guidance concerning food and non-food contact surfaces. Furthermore, our study found that chefs' hand hygiene did not meet microbiological reference standards, even after washing. Notably, Campylobacter persisted at 27 % and 30 % on chefs' hands, posing a significant risk of cross-contamination and foodborne diseases. These findings emphasize the urgent necessity for enhanced supervision of hygiene procedures and process monitoring in the HACCP-certified establishments engaged in the preparation and serving of food. Targeted interventions and food safety education for different chef subgroups can enhance food handling practices and reduce the risk of foodborne diseases in independent food establishments. • This study aimed to assess microbe contamination risk in food establishments in China. • Escherichia coli and Campylobacter were not detected in any of the cooked food samples. • Food establishments exhibited critical non-compliance with guidelines for kitchen surfaces. • Chefs' hand hygiene might possess a huge risk of cross-contamination and foodborne diseases. • Targeted interventions and education are needed to improve the awareness of safe handle practices. [ABSTRACT FROM AUTHOR]

Pathogenic microbial contamination (bacteria and fungi) in food products during production poses a significant global health risk, leading to food waste, greenhouse gas emissions, and aesthetic and financial losses. Bacteria and fungi, by forming solid biofilms, enhance their resistance to antimicrobial agents, thereby increasing the potential for cross-contamination of food products. Curcumin molecule-mediated photodynamic inactivation (Cur-m-PDI) technology has shown promising results in sterilizing microbial contaminants and their biofilms, significantly contributing to food preservation without compromising quality. Photosensitizers (curcumin) absorb light, leading to a chemical reaction with oxygen and producing reactive oxygen species (ROS) that effectively reduce bacteria, fungi, and biofilms. The mechanism of microorganism inhibition is caused by exposure to ROS generated via the type 1 pathway involving electron transfer (such as O 2 •−, H 2 O 2 , -OH•, and other radicals), the type 2 pathway involving energy transfer (such as 1O 2), secondary ROS, and weakening of antioxidant enzymes. The effectiveness of the inactivation of microorganisms is influenced by the concentration of curcumin, light (source type and energy density), oxygen availability, and duration of exposure. This article reviews the mechanism of reducing microbial food contamination and inhibiting their biofilms through Cur-m-PDI. It also highlights future directions, challenges, and considerations related to the effects of ROS in oxidizing food, the toxicity of PDI to living cells and tissues, conditions/types of food products, and the stability and degradation of curcumin. [Display omitted] • Curcumin-mediated photodynamics can inactivate bacteria, fungi, and their biofilm. • Reactive oxygen and oxidative products damage microbial cells. • Curcumin doses, light source and energy, oxygen, and exposure time affect cell death. • Food oxidation and curcumin stability and degradation are crucial for photodynamics. • Curcumin-mediated photodynamics maintain food quality and extend its shelf-life. [ABSTRACT FROM AUTHOR]

Escherichia coli is one of the most prevalent foodborne pathogens, frequently found in meat and dairy products. Current decontamination methods are often associated with changes in organoleptic characteristics, nutrient loss, and potentially harmful side effects. Furthermore, despite the array of available methods, foodborne outbreaks still frequently occur. For this reason, bacteriophages (or simply phages) emerged as a natural alternative for the biocontrol of bacterial contamination in food without altering their organoleptic properties. In this study, the potential of phage phT4A was assessed in the biocontrol of E. coli in liquid (milk) and solid (ham) food matrices. Firstly, as foods have different pH and temperature values, the influence of these parameters on phage phT4A viability was also assessed to develop an effective protocol. Phage phT4A proved to be stable for long storage periods at pH 7–8 (56 days) and temperatures of 4–37 °C (21 days). Before application of phages to inactivate pathogenic bacteria in food, previous assays were carried out in Tryptic Soy Broth (TSB) to study the dynamics of phage-bacteria interaction. Then, the antibacterial potential of phage phT4A was evaluated in the two food matrices at different temperatures (4, 10 and 25 °C). This phage was more efficient at 25 °C in all tested matrices (maximum inactivation of 6.6, 3.9 and 1.8 log CFU/mL in TSB, milk and ham, respectively) than at 10 °C (maximum decrease of 4.7, 2.1 and 1.0 log CFU/mL in TSB, milk and ham, respectively) and 4 °C (maximum reduction of 2.6 and 0.7 log CFU/mL in TSB and milk, respectively). However, the decrease of temperature from 25 °C to 10 and 4 °C prevented bacterial regrowth. The results suggest that during phage treatment, a balance between an incubation temperature that provide effective results in terms of bacterial inactivation by the phages and at the same time prevents or delays bacterial regrowth, is needed. The application of phage phT4A at a temperature of 10 °C can be an effective strategy in terms of bacterial inactivation, delaying bacterial regrowth and also reducing energy costs. • Phage phT4A was applied for the first time against Escherichia coli in milk and ham. • The impact of different conditions on phage phT4A viability was also assessed. • Phage phT4A was stable for long periods over a wide range of temperatures and pHs. • Phage phT4A effectively reduced E. coli in a matrix- and temperature-dependent way. • Phage phT4A is a potential biocontrol agent in food without impact sensory quality. [ABSTRACT FROM AUTHOR]

In this study, a multi-scale attention transformer (MSAT) was coupled with hyperspectral imaging for classifying peanut kernels contaminated with diverse Aspergillus flavus fungi. The results underscored that the MSAT significantly outperformed classic deep learning models, due to its sophisticated multi-scale attention mechanism which enhanced its classification capabilities. The multi-scale attention mechanism was utilized by employing several multi-head attention layers to focus on both fine-scale and broad-scale features. It also integrated a series of scale processing layers to capture features at different resolutions and incorporated a self-attention mechanism to integrate information across different levels. The MSAT model achieved outstanding performance in different classification tasks, particularly in distinguishing healthy peanut kernels from those contaminated with aflatoxigenic fungi, with test accuracy achieving 98.42±0.22%. However, it faced challenges in differentiating peanut kernels contaminated with aflatoxigenic fungi from those with non-aflatoxigenic contamination. Visualization of attention weights explicitly revealed that the MSAT model's multi-scale attention mechanism progressively refined its focus from broad spatial-spectral features to more specialized signatures. Overall, the MSAT model's advanced processing capabilities marked a notable advancement in the field of food quality safety, offering a robust and reliable tool for the rapid and accurate detection of Aspergillus flavus contaminations in food. • Propose a multi-scale attention transformer (MSAT) to classify fungi contamination • Design a multi-scale attention mechanism integrating a series of multi-scale layers • Find the optimal hyperparameter and evaluate the performance of the MSAT • Utilize attention weights visualization to reveal the model focused on [ABSTRACT FROM AUTHOR]

Prevalent in marine, estuarine and coastal environments, Vibrio parahaemolyticus is one of the major foodborne pathogens which can cause acute gastroenteritis through consumption of contaminated food. This study encompassed antimicrobial resistance, molecular characteristics and phylogenetic relationships of 163 V. parahaemolyticus isolated from aquatic foods across 15 provinces in China. The isolates showed high resistance rates against ampicillin (90.80 %, 148/163) and cefazolin (72.39 %, 118/163). Only 5 isolates demonstrated multi-drug resistance (MDR) phenotypes. A total of 37 different antibiotic resistance genes (ARGs) in correlation with seven antimicrobial categories were identified. tet (34) and tet (35) were present in all 163 isolates. Other most prevalent ARGs were those conferring resistance to β-lactams, with prevalence rate around 18.40 % (30/163). The virulence genes tdh and trh were found in 17 (10.43 %) and 9 (5.52 %) isolates, respectively. Totally 121 sequence types (STs) were identified through whole genome analysis, among which 60 were novel. The most prevalent sequence type was ST3 (9.20 %, 15/163), which shared the same genotype profile of trh _ , tdh + and bla CARB-22 +. Most of the tdh + V. parahaemolyticus isolates was clustered into a distinctive clade by the phylogenetic analysis. Our study showed that the antimicrobial resistance of V. parahaemolyticus in aquatic foods in China was moderate. However, the emerging of MDR isolates implicate strengthened monitoring is needed for the better treatment of human V. parahaemolyticus infections. High genetic diversity and virulence potential of the isolates analyzed in this study help better understanding and evaluating the risk of V. parahaemolyticus posed to public health. • MDR V. parahaemolyticus isolates appeared in a specific region of China. • One trh + MDR V. parahaemolyticus was found. • The most prevalent sequence type ST3 all harbored tdh and bla CARB. • The majority of the tdh + isolates were clustered into a distinctive clade. [ABSTRACT FROM AUTHOR]

Foodborne illnesses involving raw and minimally processed foods are often caused by human noroviruses (HuNoV) and hepatitis A virus (HAV). Since food is contaminated usually with small numbers of virions, these must be eluted from the food surface and then concentrated for detection. The objective of this study was to optimize an ultrafiltration (UF) concentration method for HAV and HuNoVs present on various fresh and frozen produce. The detection range of the optimized method and its applicability to different food matrices was compared to the reference method ISO 15216-1:2017. Strawberry, raspberry, blackberry, lettuce, and green onion (25 g) were contaminated with HAV, HuNoV GI.7 and HuNoV GII.4 and then recovered therefrom by elution. A commercial benchtop UF device was used for the concentration step. Viral RNA was extracted and detected by RT-qPCR. From fresh strawberries, recovery of HAV loaded at 104 genome copies per sample was 30 ± 13 %, elution time had no significant impact, and UF membrane with an 80–100 kDa cut-off in combination with Tris-glycine elution buffer at pH 9.5 was found optimal. At lower copy numbers on fresh strawberry, at least 1 log lower numbers of HuNoV were detectable by the UF method (103 vs 104 GII.4 copies/sample and 101 vs 103 GI.7 copies/sample), while HAV was detected at 101 genome copies/sample by both methods. Except on raspberry, the UF method was usually equivalent to the ISO method regardless of the virus tested. The UF method makes rapid viral concentration possible, while supporting the filtration of large volume of sample. With fewer steps and shorter analysis time than the ISO method, this method could be suitable for routine analysis of viruses throughout the food production and surveillance chain. • Ultrafiltration (UF) can be used to concentrate viruses from fresh and frozen produce. • Low numbers of enteric viruses on strawberry can be detected using UF. • Viral concentration by UF and by ISO method 15,216–1 are equivalent on various produce. • Raspberry presents challenges associated with UF virus recovery. • The UF method appears to be suitable for routine analysis of viruses in produce. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes is a foodborne pathogen that can cause deadly severe listeriosis. While systematic review and meta-analysis are powerful tools for comprehensive analysis by pooling every related study, these approaches to L. monocytogenes contamination food have yet to be studied in South Korea. We aimed to identify high-risk L. monocytogenes foods in South Korea through a prevalence survey of retail food products for the first time. A total of 13,684 samples of 59 articles were used for meta-analysis through the systematic review, and the results were synthesized using a random-effects model considering the heterogeneity. The overall pooled prevalence was 2.26 % (95 % CI: 1.44–3.52 %). Among nine food categories, meat exhibited the highest prevalence at 8.32 % (95 % CI: 4.42–12.14 %) after sample size restriction. Specifically, a post-hoc sensitivity analysis was conducted to identify the prevalence difference among subgroups and the source of heterogeneity. Intriguingly, the analysis revealed chicken as the primary contributor to the elevated prevalence of L. monocytogenes , a key factor deriving the observed heterogeneity. This study carries significant implications for public health and food safety in Korea. Furthermore, knowledge of differences in prevalence levels in various foods will be able to be used as a predictive guideline for foodborne outbreaks. • First systematic review and meta-analysis were conducted for L. monocytogenes in South Korea. • The overall rate of L. monocytogenes contamination in retail food was 2.26 %. • Poultry and meat exhibited the highest prevalent food type at 8.32 %. • Meta-analysis with sample size restriction could mitigate the potential bias with lowered heterogeneity. • Through post-hoc sensitivity analysis, chicken was the predominant contamination subgroup. [ABSTRACT FROM AUTHOR]

Human noroviruses (HuNoVs) are the most predominant viral agents of acute gastroenteritis. Vegetables are important vehicles of HuNoVs transmission. This study aimed to assess the HuNoVs prevalence in vegetables. We searched the Web of Science, Excerpta Medica Database, PubMed, and Cochrane databases until June 1, 2023. A total of 27 studies were included for the meta-analysis. Statistical analysis was conducted using Stata 14.0 software. This analysis showed that the pooled HuNoVs prevalence in vegetables was 7 % (95 % confidence interval (CI): 3–13) worldwide. The continent with largest number of studies was Europe, and the highest number of samples was lettuce. As revealed by the results of the subgroup meta-analysis, the prevalence of GI genogroup was the highest (3 %, 95 % CI: 1–7). A higher prevalence was seen in vegetables from farms (18 %, 95 % CI: 5–37), while only 4 % (95 % CI: 1–8) in retail. The HuNoVs prevalence of ready-to-eat vegetables and non-ready-to-eat vegetables was 2 % (95 % CI: 0–8) and 9 % (95 % CI: 3–16), respectively. The prevalence by quantitative real time RT-PCR was 8 % (95 % CI: 3–15) compared to 3 % (95 % CI: 0–13) by conventional RT-PCR. Furthermore, the HuNoVs prevalence in vegetables was 6 % (95 % CI: 1–14) in ISO pretreatment method and 8 % (95 % CI: 1–19) in non-ISO method, respectively. This study is helpful in comprehensively understanding the prevalence of HuNoVs contamination in vegetables worldwide. • Field studies on human noroviruses (HuNoVs) contamination in vegetables worldwide were reviewed. • We found a higher prevalence of HuNoVs GI than GII in vegetables. • Prevalence of HuNoVs in vegetables varied across packagings and between sources. • Most of samples testing were done in accordance with the standard ISO, compared to other methods. • We urge studies monitoring HuNoVs in vegetables to help with management and control of this issue. [ABSTRACT FROM AUTHOR]

Viability RT-qPCR, a molecular detection method combining viability marker pre-treatment with RT-qPCR, has been proposed to infer infectivity of viruses which is particularly relevant for non-culturable viruses or sophisticated cell culture systems. Being human noroviruses (HuNoV) most frequently associated with foodborne outbreaks, this study compared different viability techniques and infectivity in human intestinal enteroids (HIE) to ultimately determine whether the molecular approaches could serve as rapid assays to predict HuNoV inactivation in high-risk food. To this end, the performance of three viability RT-qPCR assays with different intercalating markers ((Viability PCR Crosslinker Kit (CL), propidium monoazide (PMAxx™), and platinum chloride (PtCl 4)) in estimating survival of HuNoV exposed to thermal and high pressure (HPP) treatments was compared to replication tested in the HIE cell culture model. A nearly full-length genomic molecular assay coupled with PMAxx™ to infer HuNoV thermal inactivation was also assessed. The experimental design included HuNoV genogroup I.3 [P13], GII.4 Sydney [P16], GII.6 [P7], along with Tulane virus (TV) serving as surrogate. Finally, viability RT-qPCR was tested in HPP-treated strawberry puree, selected as a food matrix with high viral contamination risk. PMAxx™ and CL performed evenly, while PtCl 4 affected HuNoV infectivity. Taking all experimental data together, viability RT-qPCR was demonstrated to be an improved method over direct RT-qPCR to estimate viral inactivation at extreme thermal (95 °C) and HPP (450 MPa) exposures, but not under milder conditions as amplification signals were detected. Despite its complexity and limitations, the HIE demonstrated a more robust model than viability RT-qPCR to assess HuNoV infectivity. • Viability RT-qPCR and replication in human intestinal enteroids (HIE) were compared using human norovirus (HuNoV). • Platinum chloride (PtCl 4), as viability marker, affected HuNoV infectivity. • Viability RT-qPCRs detected HuNoV inactivation at extreme thermal and pressure conditions only. • Replication in HIE was a more robust assay than viability RT-qPCRs to infer HuNoV infectivity. [ABSTRACT FROM AUTHOR]

Fusarium verticillioides is one of the important mycotoxigenic pathogens of maize since it causes severe yield losses and produces fumonisins (FBs) to threaten human and animal health. Previous studies showed that temperature and water activity (a w) are two pivotal environmental factors affecting F. verticillioides growth and FBs production during maize storage. However, the genome-wide transcriptome analysis of differentially expressed genes (DEGs) in F. verticillioides under the stress combinations of temperature and a w has not been studied in detail. In this study, DEGs of F. verticillioides and their related regulatory pathways were analyzed in response to the stress of temperature and a w combinations using RNA-Seq. The results showed that the optimal growth conditions for F. verticillioides were 0.98 a w and 25 °C, whereas the highest per-unit yield of the fumonisin B 1 (FB 1) was observed at 0.98 a w and 15 °C. The RNA-seq analysis showed that 9648 DEGs were affected by temperature regardless of a w levels, whereas only 218 DEGs were affected by a w regardless of temperature variations. Gene Ontology (GO) analysis revealed that a decrease in temperature at both a w levels led to a significant upregulation of genes associated with 24 biological processes, while three biological processes were downregulated. Furthermore, when a w was decreased at both temperatures, seven biological processes were significantly upregulated and four were downregulated. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that the genes, whose expression was upregulated when the temperature decreased, were predominantly associated with the proteasome pathway, whereas the genes, whose expression was downregulated when the a w decreased, were mainly linked to amino acid metabolism. For the FB 1 , except for the FUM15 gene, the other 15 biosynthetic-related genes were highly expressed at 0.98 a w and 15 °C. In addition, the expression pattern analysis of other biosynthetic genes involved in secondary metabolite production and regulation of fumonisins production was conducted to explore how this fungus responds to the stress combinations of temperature and a w. Overall, this study primarily examines the impact of temperature and a w on the growth of F. verticillioides and its production of FB 1 using transcriptome data. The findings presented here have the potential to contribute to the development of novel strategies for managing fungal diseases and offer valuable insights for preventing fumonisin contamination in food and feed storage. • Higher temperature (25 °C) and higher water activity (0.98 a w) favored the growth of Fusarium verticillioides • Lower temperature (15 °C) and higher water activity (0.98 a w) favored the fumonisin B 1 production in F. verticillioides • Secondary metabolite gene clusters were differentially expressed under temperature/water activity stresses. • The RNA-seq analysis provides gene groups for further investigation of fumonisin biosynthesis in F. verticillioides [ABSTRACT FROM AUTHOR]

Listeriosis remains one of the most severe foodborne diseases regarding mortality rate. L. monocytogenes can grow under stressful conditions and contaminate various food categories. Regulation (EC) No 2073/2005 modified on microbiological criteria for foodstuffs includes either qualitative or quantitative food safety criteria on L. monocytogenes and mentions EN ISO 11290-1 Standard as the reference detection method. The use of alternative certified methods is allowed at European level for own checks and by certain European countries in the frame of official controls. Here we report the comparison of alternative certified methods for the detection of L. monocytogenes , according to the criteria expressed by the National Reference Laboratories (NRLs) for L. monocytogenes network in Europe, through an enquiry conducted in 2022 by the European Union Reference Laboratory (EURL) for L. monocytogenes. Emerging detection methods make it possible to diversify the panel of available detection methods. Each method has advantages and limitations and the choice of a method depends on the needs, organization and objectives of the laboratory. Our study focused on a comparison by category in order to provide an overview of the differences between the methods as complete and simple as possible, mainly by examining the certification files of the alternative methods, which constitute a reliable and publicly accessible source of information about performances of the methods. • European regulation allows certified methods for L. monocytogenes detection. • We report comparison of methods categories for L. monocytogenes detection. • Choice depends on the needs, organization and objectives of the laboratory. • Certification files constitute reliable public information about performances. [ABSTRACT FROM AUTHOR]

Contamination of food by multidrug-resistant (MDR) bacteria is a potential threat to consumers. Aquatic products are increasingly consumed due to their high value and rich nutrient. Nevertheless, the prevalence of multi-drug resistant (MDR) E. coli in retail aquatic products has not been systematically investigated in China. In this study, we conducted a national investigation on the prevalence of E. coli and MDR E. coli in retail aquatic products and the characteristics of the MDR E. coli isolates. A total of 849 samples consisting of 680 fish, 143 shrimp, and 26 shellfish were purchased from markets in 39 cities in China and investigated for the presence of E. coli. Overall, 340 (40.0 %) and 169 (19.9 %) samples were contaminated with E. coli and MDR E. coli , indicating poor hygiene conditions of retail aquatic products. A total of 190 MDR E. coli were isolated, which were recovered from 38.5 % shellfish, 20.1 % shrimp, and 19.0 % fish. Thirty-two ESBL-producing E. coli were identified from 3.5 % fish, 3.5 % shrimp, and 3.8 % shellfish. The MDR E. coli isolates showed a high prevalence of resistance to tetracycline (93.7 %), trimethoprim-sulfamethoxazole (78.9 %), ampicillin (78.4 %), chloramphenicol (72.1 %), nalidixic acid (73.2 %), cephalothin (65.3 %), and streptomycin (65.8 %). Resistances to kanamycin (42.1 %), gentamicin (37.9 %), ciprofloxacin (42.6 %), and norfloxacin (45.8 %) were also common. Further, 15.3 % and 8.4 % of the isolates were resistant to cefotaxime and ceftazidime, respectively. Four isolates were resistant to colistin. More than 85.0 % of the isolates were resistant to 5–15 antibiotics. Of the antibiotic resistance genes, TEM-1, tetA , strA/B , sul2 , aadA , floR , and qnrS were the most prevalent, followed by sul1 , aac(6′)-Ib , oqxA/B , cmlA and aphA1. Six CTX-M-types were found, among which CTX-M-55 and CTX-M-14 were predominant. All 4 colistin-resistant isolates carried the mcr-1 gene, of which three were ESBL strains. WGS indicated that the mcr-1 gene was located on two types of plasmids (IncHI2 and IncX4). Conjugation experiments showed the mcr-1 gene could be transferred to E. coli C600. To our knowledge, this is the first report of mcr-1 -positive ESBL E. coli (ST10 and ST2705) in retail aquatic products. The emergence of such strains poses a serious threat to consumers, with the potential to spread resistance genes to humans. Our results indicate that retail aquatic products are important reservoirs of MDR E. coli and facilitate the dissemination of the resistance genes. Continuous surveillance and interventions of restricting antibiotic use in aquatic environments should also be applied to reduce the prevalence of MDR bacteria. • High prevalence of multidrug-resistant E. coli was observed in retail aquatic products. • Six CTX-M types were found with CTX-M-55 and CTX-M-14 as the predominant types. • This is the first report of mcr-1 -positive ESBL-producing E. coli ST2705 and ST10 in retail fish. • Two plasmids bearing mcr-1 (IncHI2 and IncX4) were found in retail fish. [ABSTRACT FROM AUTHOR]

Control of bacterial spores continues to be one of the main challenges for the food industry due to their wide dissemination and extremely high resistance to processing methods. Furthermore, the large variability in heat resistance in spores that contaminate foods makes it difficult to establish general processing conditions. Such heterogeneity not only derives from inherent differences among species and strains, but also from differences in sporulation environments that are generally ignored in spores encountered in foods. We evaluated heat inactivation kinetics and the thermodependency of resistance parameters in B. subtilis 168 spores sporulated at adverse temperatures, water activity (a w), and pH, applying an experimental approach that allowed us to quantitatively compare the impact of each condition. Reduction of incubation temperature from the optimal temperature dramatically reduced thermal resistance, and it was the most influential factor, especially at the highest treatment temperatures. These spores were also more sensitive to chemicals presumably acting in the inner membrane. Reducing sporulation a w increased heat resistance, although the magnitude of that effect depended on the solute and the treatment temperature. Thus, changes in sporulation environments varied 3D 100°C values up to 10.4-fold and z values up to 1.7-fold, highlighting the relevance of taking such a source of variability into account when setting heat processing conditions. UV-C treatment and sodium hypochlorite efficiently inactivated all spore populations, including heat-resistant ones produced at low a w. • Impact of sporulation conditions was studied using comparable stress levels. • 3D 100°C varied by 10.4-fold and z by 1.7-fold with sporulation conditions. • Low sporulation temperature was the most influencing factor. • Spores obtained at low a w presented increased heat resistance. • UV-C and sodium hypochlorite effectively inactivated heat resistant spores. [ABSTRACT FROM AUTHOR]

Salmonella enterica subsp. enterica serotype Rissen is the predominant serotype found in Thai pork production and can be transmitted to humans through contamination of the food chain. This study was conducted to investigate the genetic relationships between serovar Rissen isolates from all levels of the pork production chain and evaluate the ability of the in silico antimicrobial resistance (AMR) genotypes to predict the phenotype of serovar Rissen. A total of 38 serovar Rissen isolates were tested against eight antibiotic agents by a disk diffusion method and the whole genomes of all isolates were sequenced to detect AMR genetic elements using the ResFinder database.A total of 86.84% of the isolates were resistant to tetracycline, followed by ampicillin (78.96%) and sulfonamide-trimethoprim (71.05%). Resistance to more than one antimicrobial agent was observed in 78.95% of the isolates, with the most common pattern showing resistance to ampicillin, chloramphenicol, streptomycin, sulfonamide-trimethoprim, and tetracycline. The results of genotypic AMR indicated that 89.47% of the isolates carried tet(A) , 84.22% carried bla TEM-1B , 78.95% carried sul3 , and 78.95% carried dfrA12. The genotypic prediction of phenotypic resistance resulted in a mean sensitivity of 97.45% and specificity of 75.48%. Analysis by core genome multilocus sequence typing (cgMLST) demonstrated that the Salmonella isolates from various sources and different locations shared many of the same core genome loci. This implies that serovar Rissen has infected every stage of the pork production process and that contamination can occur in every part of the production chain. • S. Rissen from the different stages of the pork production chain were genetically related based on cgMLST analysis. • S. Rissen can persist and cross/re-contamination can occur in all steps of the pork production chain. • Phenotype of antimicrobial resistance to antimicrobials are accurately predicted using WGS data. [ABSTRACT FROM AUTHOR]

The increasing antimicrobial resistance (AMR) among pathogenic and opportunistic pathogenic microorganisms is one of the main global public health problems. The consumption of food contaminated with such bacteria (ARB), especially of raw products, might result in the direct acquisition of ARB and in a spread of resistant bacteria along the food chain. The aim of the study was to characterize the antimicrobial susceptibility of potentially extended spectrum β-lactamase (ESBL) producing or AmpC resistant Enterobacteriaceae isolated from the surface of 147 muskmelons from wholesale and retail. A phenotypic analysis was carried out by using minimum inhibitory concentration (MIC) test strips for ESBL detection and MIC susceptibility plates against 14 antimicrobials. Furthermore, ESBL genes, sul -genes and plasmid-mediated AmpC resistance were analyzed by real-time PCR. Additionally, a further insight in the AmpC resistance of isolates of the Enterobacter cloacae complex (ECC) was obtained by analyzing the sequence of the ampC regulatory region (n = 15). A total of 73 potentially resistant Enterobacteriaceae were isolated from 56 muskmelons. Of these, 15 isolates of the ECC were suspicious for ESBL/AmpC resistance, and eleven thereof were positive for the AmpC family EBC. Phenotypic analysis showed diminished susceptibility against "critically" and "highly important" antimicrobials, according to the WHO classification. Furthermore, divergence in the ampC regulatory region was detected between the 15 isolates. These findings highlight the important role that raw produce might play in the transmission of antimicrobial resistances along the food chain. • A total of 15 AMR ECC strains were isolated from 15 of the 147 analyzed muskmelons. • Eleven ECC isolates were additionally positive for AmpC EBC plasmid. • All ECC isolates were negative for ESBL-/ sul -genes. • Analyzed ampR gene of ECC isolates showed heterogeneity even within same species. [ABSTRACT FROM AUTHOR]

The most important mode of transmission causing outbreaks of Chagas disease in the Amazon region is the oral route due to the ingestion of contaminated food. Herein, prevention methods for foodborne diseases caused by Trypanosoma cruzi , namely, sanitization, thermal treatment were investigated and the use of reverse transcription PCR (RT-PCR) amplification for the mRNA-based detection of viable T. cruzi in açai, was developed. Three T. cruzi strains (T. cruzi I, T. cruzi III and Y) were used in the present study. The Amazonian strains T. cruzi I (425) and T. cruzi III (370) showed higher resistance to sodium hypochlorite treatment and heat treatment than the reference strain Y. The blanching of fruits (70 ± 1 °C for 10 s) and pasteurization of juice (82.5 °C for 1 min) efficiently eliminated T. cruzi in food matrices. Additionally, a method that uses RT-PCR amplification of mRNA was developed for the detection of viable T. cruzi in açai, which could play a role in examining food samples, ensuring consumer health, and reducing this foodborne disease. • Prevention methods for oral transmission in food matrices were evaluated. • Blanching and pasteurization are efficient technologies to eliminate T. cruzi. • An RT-PCR assay for the detection of viable T. cruzi was developed. [ABSTRACT FROM AUTHOR]

Clostridium difficile is a major cause of infectious diarrhea associated to healthcare settings. Community-acquired infections are increasingly reported in the last decade and exposure other than to symptomatic patients rather to contaminated foods or animals is feasible. Occurrence of C. difficile in shellfish raises concern because spores can survive the cooking temperatures given that shellfish is often consumed poorly cooked or raw. Aim of our study was to investigate whether shellfish represents a reservoir of C. difficile human PCR-ribotypes (RTs). 702 shellfish samples of farmed and wild bivalve mollusc species were collected over the 2015–2017 period in North Adriatic Italian Sea to investigate contamination with C. difficile and characterize the isolates in terms of genotypic variability and antimicrobial resistance profile. C. difficile was detected in 16.9% (CI: 14.1%–19.8%) samples: 11.6% mussels and 23.2% clams. Compared to mussels, clams were significantly associated with detection of C. difficile (OR = 2.4, P < 0.01). Overall 113 C. difficile isolates were genotyped and 75 (66.4%) were toxigenic. Fifty-three different RTs were identified. 40.7% C. difficile isolates were among the RTs most commonly involved in human infection in Europe. The profile of antimicrobial susceptibility was determined by E-test; microbiological resistance was frequent against clindamycin (17%), erythromycin (23%), rifampicin (8.8%) and moxifloxacin (10.6%). All isolates were susceptible to metronidazole and one showed MIC > ECOFF for vancomycin. C. difficile strains showed high variety in RTs, most of them already detected in other animals or known as highly virulent and epidemic in humans. These results prompt towards investigating on specific risk mitigation measures against C. difficile and are preliminary for any source attribution and risk assessment study. • 118/702 (16.9%, CI: 14.1%–19.8%) marine bivalve mollusc samples contaminated with C. difficile • High genotypic diversity of C. difficile isolates (53 PCR-ribotypes/113 isolates) • 66.4% C. difficile isolates toxigenic, some hypervirulent • 40.7% of C. difficile isolates overlap with PCR-ribotypes commonly isolated from C. difficile infection (CDI) in Europe. • Compared to mussels, clams have 2.4 more odds to be contaminated with C. difficile. [ABSTRACT FROM AUTHOR]

Abstract The presence of Aspergillus section Flavi and aflatoxins in sugarcane as well as in by-products, such as molasses, sugar, yeast cream and dried yeast, collected from different fields and processing plants in São Paulo state, were investigated throughout the sugarcane production chain. A total of 246 samples was collected and analyzed and 226 isolates of Aspergillus section Flavi were isolated. Aspergillus section Flavi strains were found in sugarcane juice, milled sugarcane, stalk, soil and dried yeast samples. Among the isolates of Aspergillus section Flavi submitted to polyphasic identification (n = 57), Aspergillus novoparasiticus and Aspergillus arachidicola were predominantly found. A significant proportion of the isolates (84.5%) were found to have morphological and physiological characteristics of A. novoparasiticus. Most samples, with the exception of sugar, showed some aflatoxin contamination. The highest level was in dried yeast with an average of 2.55 μg/kg and maximum value of 10.19 μg/kg. This is the first report of contamination of sugarcane by A. novoparasiticus. Highlights • Aspergillus section Flavi and aflatoxins were investigated from ethanol and sugar production chain. • The highest aflatoxins contamination occurred in dried yeast. • Aspergillus novoparasiticus was isolated for the first time from sugarcane and soil. [ABSTRACT FROM AUTHOR]

Abstract The effects of surface coating, microbial loading, surface-to-volume ratio, sample stacking, mixing of samples with romaine lettuce, and shaking of the samples on the inactivation of Salmonella contaminating boiled chicken breast (BCB) cubes using in-package atmospheric dielectric barrier discharge cold plasma (ADCP) treatment at 38.7 kV were investigated. Whey protein coating increased the ADCP treatment efficacy in inactivating Salmonella on BCB cubes; the D -value increased from 0.2 to 1.3 min when the initial inoculum concentration increased from 3.8 to 5.7 log CFU/sample. ADCP decontaminated stacked BCB samples uniformly, and shaking during the treatment increased the inactivation rate. The concentrations of chicken protein isolate, water, and soybean oil in a chicken breast model food that resulted in the highest Salmonella reduction (1.7 log CFU/sample) were 20.5%, 68.9%, and 10.6%, respectively. ADCP treatment did not affect the color and tenderness of the model food, irrespective of its composition. The present study indicated that ADCP is a feasible technology to decontaminate prepackaged ready-to-eat meat cube products. Highlights • Atmospheric cold plasma (CP) decontaminates lettuce-mixed boiled chicken meat cubes. • Meat cube coating aids effective inactivation of Salmonella on chicken breast. • Chicken composition affects the microbial reduction efficacy of CP treatment (CPT). • CPT with shaking uniformly decontaminates a chicken-salad model food. • CPT does not affect the color and tenderness of chicken and chicken model foods. [ABSTRACT FROM AUTHOR]

Abstract Epicoccum sorghinum isolates from sorghum grain grown in Brazil were characterized using a polyphasic approach based on morphological, genetic and physiologic features. A considerable intraspecific variability was observed. The phylogenetic analysis showed that the 53 isolates studied formed four distinct clades, and their morphological features revealed a high variability in culture. The four clades could not be distinguished clearly by morphology or enzyme production patterns. The tenuazonic acid (TeA) production capability of 11 isolates was also determined and revealed a good agreement with the phylogeny results. All of the 11 isolates were revealed as TeA producers, indicating a potential toxicological risk to sorghum crops. This is the first study to provide a detailed morphological description of E. sorghinum isolates from sorghum grains in Brazil and it clearly confirms the wide genetic and phenotypic variability previously reported for this species in other countries. Highlights • Polyphasic characterization of an important sorghum grain mold fungus • Intraspecific variability was found in Epicoccum sorghinum isolated from Brazil. • High levels of tenuazonic acid were produced by E. sorghinum isolates. • E. sorghinum may play a role in TeA contamination on sorghum grains. [ABSTRACT FROM AUTHOR]

Abstract Although hepatitis E virus (HEV) transmission has been demonstrated after consumption of products containing infected pig liver, human cases can be also associated with other pig meat products, such as sausages. Data on HEV viremia and dissemination in muscle meat of infected animals are still sparse, especially during long-term infection. Previously, we have shown that experimental co-infection of pigs with HEV and porcine reproductive and respiratory syndrome virus (PRRSV) lengthens HEV infection up to 49 days and increases the likelihood of the presence of HEV RNA in the liver of the pig at a later stage of infection. In the present study, we show that during experimental HEV-PRRSV co-infection, prolonged HEV viremia, up to 49 days post-inoculation (dpi), is detected. The long-term viremia observed was statistically associated with the absence of HEV seroconversion. HEV RNA was also frequently detected, at a late stage of infection (49 dpi), in the three different types of muscle tested: femoral biceps, psoas major or diaphragm pillar. The HEV RNA load could reach up to 1 · 106 genome copies per gram of muscle. Detection of HEV in muscle meat was statistically associated with high HEV loads in corresponding liver and fecal samples. The presence of HEV in pig blood, femoral biceps and major psoas, corresponding to ham and tenderloin muscles respectively, is of concern for the food industry. Hence, these results indicate new potential risks for consumers and public health regarding pork products. Highlights • Long-lasting HEV viremia in pigs supports the possible contamination of products containing pig blood or derivatives • HEV was detected in pig muscle (ham and tenderloin) after experimental co-infection of pigs with HEV and PRRSV • New experimental evidence of HEV contamination in pig muscle supports that various pork products are a risk for HEV exposure [ABSTRACT FROM AUTHOR]

Abstract Aspergilli are common contaminants of food and feed and a major source of mycotoxins. In this study, 87 Aspergillus strains were isolated from beans from 14 different cities in Brazil and identified to the species level based on partial calmodulin and β-tubulin sequence data. All green spored isolates belonged to section Flavi and were identified as A. flavus (n = 39) or A. pseudocaelatus (n = 1). All black spored isolates belonged to section Nigri and were identified as A. niger (n = 24) or A. luchuensis (n = 10), while the yellow spored strains were identified as A. westerdijkiae (n = 7), A. ostianus (n = 3), A. ochraceus (n = 1) or A. wentii (n = 2). The toxigenic potential of these Aspergillus strains from beans was studied by the prospection of genes in three of the major mycotoxin clusters: aflatoxin (seven genes checked), ochratoxin A (four genes) and fumonisin (ten genes and two intergenic regions). Genes involved in the biosynthesis of aflatoxin were only detected in A. flavus isolates: 17/39 A. flavus isolates proved to contain all the aflatoxin genes tested, the others missed one or more genes. The full complement of fumonisin biosynthesis genes was identified in all A. niger isolates. Finally, no genes for ochratoxin A were detected in any of the isolates. Our work suggests that aflatoxin production by some A. flavus strains and fumonisin production by A. niger isolates form the largest mycotoxin risks in Brazilian beans. Highlights • Molecular identification of Brazilian strains of Aspergillus associated with beans • Prospection of genes involved on aflatoxin, ochratoxin and fumonisin biosynthesis • Suggests a potentially high risk of daily intake of mycotoxins by the population [ABSTRACT FROM AUTHOR]

Abstract The methods for the detection and enumeration of Enterobacteriaceae , described in EN ISO 21528, parts 1 and 2, were validated by order of the European Commission under the mandate M/381. Fourteen laboratories from seven European countries participated in the collaborative trials, organized by The Netherlands Food and Consumer Product Safety Authority (Wageningen/Utrecht, The Netherlands). Five different matrices from different food categories were selected to be tested in the collaborative trials, in order to validate the method horizontally, according to ISO 16140. The matrices included meat, tiramisu, infant formula, liquid egg, smoked salmon (detection method only) and animal feed (enumeration method only). The raw meat and liquid egg were naturally contaminated and the other matrices were artificially contaminated with a cocktail of four different Enterobacteriaceae strains. The samples used in the trial were tested for homogeneity and stability before distribution. The method for detection of Enterobacteriaceae showed a specificity and sensitivity above 95% for all matrices. The method for the enumeration had a repeatability limit r of 0.37 (expressed as a difference between log 10 -transformed test results) and a reproducibility limit R of 0.87 (expressed as a difference between log 10 -transformed test results). The validation data were incorporated in the newly published ISO standards EN ISO 21528:2017- Microbiology of the food chain - Horizontal methods for the detection and enumeration of Enterobacteriaceae - Part 1: Detection method, and Part 2: Colony-count technique. [ABSTRACT FROM AUTHOR]

Abstract The European and International Standard method for the detection of Salmonella spp. in samples from the primary production stage, EN ISO 6579:2002/Amd.1:2007, was validated by an interlaboratory study in the frame of Mandate M/381, ordered by the European Commission and accepted by the European Standardisation Organisation (CEN). In addition to this study, results from two interlaboratory studies organised earlier by the European Union Reference Laboratory (EURL) for Salmonella were used for determination of the performance characteristics. Parallel to the performance evaluation for the Mandate, the revision of EN ISO 6579:2002 started. Part of this revision was the incorporation of the standardised method for detection of Salmonella in samples from the primary production stage (EN ISO 6579:2002/Amd.1:2007) and its performance characteristics in the new part 1 of EN ISO 6579. The 2002 version of EN ISO 6579 already contained performance characteristics for the detection of Salmonella in food samples, but LOD 50 values (contamination level at which 50% of the samples are found positive) were not yet included. To be in line with the performance characteristics determined for detection of Salmonella spp. in samples from the primary production stage, LOD 50 values for detection of Salmonella in food samples were calculated from the raw data of the validation studies performed in 2000. In this paper, the performance characteristics of EN ISO 6579-1:2017 are determined based not only on the results of the interlaboratory study carried out in 2013 under the Mandate, but also on several other interlaboratory studies. These performance characteristics consist of specificity, sensitivity and LOD 50. [ABSTRACT FROM AUTHOR]

Abstract A method for the quantification of the Bacillus cereus emetic toxin (cereulide) was developed and validated. The method principle is based on LC-MS as this is the most sensitive and specific method for cereulide. Therefore the study design is different from the microbiological methods validated under this mandate. As the method had to be developed a two stage validation study approach was used. The first stage (pre-study) focussed on the method applicability and the experience of the laboratories with the method. Based on the outcome of the pre-study and comments received during voting at CEN and ISO level a final method was agreed to be used for the second stage the (final) validation of the method. In the final (validation) study samples of cooked rice (both artificially contaminated with cereulide or contaminated with B. cereus for production of cereulide in the rice) and 6 other food matrices (fried rice dish, cream pastry with chocolate, hotdog sausage, mini pancakes, vanilla custard and infant formula) were used. All these samples were spiked by the participating laboratories using standard solutions of cereulide supplied by the organising laboratory. The results of the study indicate that the method is fit for purpose. Repeatability values were obtained of 0.6 μg/kg at low level spike (ca. 5 μg/kg) and 7 to 9.6 μg/kg at high level spike (ca. 75 μg/kg). Reproducibility at low spike level ranged from 0.6 to 0.9 μg/kg and from 8.7 to 14.5 μg/kg at high spike level. Recovery from the spiked samples ranged between 96.5% for mini-pancakes to 99.3% for fries rice dish. [ABSTRACT FROM AUTHOR]

Abstract Hepatitis A virus (HAV) and norovirus are important agents of food-borne human viral illness, with common vehicles including bivalve molluscan shellfish, soft fruit and various vegetables. Outbreaks of viral illness due to contamination of the surfaces of foods, or food preparation surfaces by for example infected food handlers are also common. Virus analysis of food matrices can contribute towards risk management for these hazards and a two-part technical specification for determination of Hepatitis A virus and norovirus in food matrices (ISO/TS 15216:2013) was published jointly by the European Committee for Standardisation and the International Organization for Standardization in 2013. As part of the European Mandate No. M381 to validate 15 standards in the field of food microbiology, an international validation study involving 18 laboratories from 11 countries in Europe was conducted between 2012 and 2014. This study aimed to generate method characteristics including limit of detection, limit of quantification, repeatability and reproducibility for ISO 15216 – Part 1, the method for quantification, in seven food matrices. The organization and results of this study, including observations that led to improvements in the standard method are presented here. After its conclusion, the method characteristics generated were added to the revised international standard, ISO 15216-1:2017, published in March 2017. [ABSTRACT FROM AUTHOR]

Abstract Foods and beverages are nutrient-rich ecosystems in which most microorganisms are able to grow. Moreover, several factors, such as physicochemical characteristics, storage temperature, culinary practices, and application of technologies for storage, also define the microbial population of foods and beverages. The yeast population has been well-characterised in fresh and processed fruit and vegetables, dairy products, dry-cured meat products, and beverages, among others. Some species are agents of alteration in different foods and beverages. Since the most comprehensive studies of spoilage yeasts have been performed in the winemaking process, hence, these studies form the thread of the discussion in this review. The natural yeast populations in raw ingredients and environmental contamination in the manufacturing facilities are the main modes by which food contamination occurs. After contamination, yeasts play a significant role in food and beverage spoilage, particularly in the alteration of fermented foods. Several mechanisms contribute to spoilage by yeasts, such as the production of lytic enzymes (lipases, proteases, and cellulases) and gas, utilisation of organic acids, discolouration, and off-flavours. This review addresses the role of yeasts in foods and beverages degradation by considering the modes of contamination and colonisation by yeasts, the yeast population diversity, mechanisms involved, and the analytical techniques for their identification, primarily molecular methods. Highlights • Raw material, plant facilities, air and water are main source of spoilage yeasts. • Origin of contamination by Brettanomyces / Dekkera during winemaking • Independent- and dependent-culture molecular methods of yeast identification • Recent reports of yeast spoilage in foodstuffs [ABSTRACT FROM AUTHOR]

Abstract Kitchen mishandling practices contribute to a large number of foodborne illnesses. In this study, the transfer and cross-contamination potential of Vibrio parahaemolyticus from bloody clams to ready-to-eat food (lettuce) was assessed. Three scenarios were investigated: 1) direct cross-contamination, the transfer of V. parahaemolyticus from bloody clams to non-food contact surfaces (hands and kitchen utensils) to lettuce (via slicing), was evaluated; 2) perfunctory decontamination, the efficacy of two superficial cleaning treatments: a) rinsing in a pail of water, and b) wiping with a kitchen towel, were determined; and 3) secondary cross-contamination, the microbial transfer from cleaning residuals (wash water or stained kitchen towel) to lettuce was assessed. The mean of percent transfer rates through direct contact was 3.6%, and an average of 3.5% of total V. parahaemolyticus was recovered from sliced lettuce. The attempted treatments reduced the transferred population by 99.0% (rinsing) and 94.5% (wiping), and the relative amount of V. parahaemolyticus on sliced lettuce was reduced to 0.008%. V. parahaemolyticus exposure via secondary cross-contamination was marginal. The relative amount of V. parahaemolyticus recovered from washed lettuce was 0.07%, and the transfers from stained kitchen towel to lettuce were insubstantial. Our study highlights that V. parahaemolyticus was readily spread in the kitchen, potentially through sharing of non-food contact surfaces. Results from this study can be used to better understand and potentially raising the awareness of proper handling practices to avert the spread of foodborne pathogens. Highlights • Improper kitchen hygiene practices facilitate Vibrio parahaemolyticus dissemination in the kitchen. • Superficial treatments significantly reduced the bacterial count, but were insufficient to eliminate them. • Awareness of proper handling practices should be encouraged. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes can adapt, persist, and form biofilms on food premises surfaces, representing a challenge for food safety, since they led to disease transmission, food contamination and spoilage during production. Physical interventions (scrubbing and wiping) can help controlling formation, nevertheless when biofilms are formed, they are usually very resistant to current control strategies used in the food industry. Biofilm attachment and formation is influenced by environment characteristics, substrate properties and microbial motility. The purpose of this study was to evaluate the ability of L. monocytogenes to attach and form biofilms on different surfaces (wood, nylon, and polycarbonate) representative of the materials used during produce harvesting and storage. Multi-strain L. monocytogenes biofilms were grown in a CDC Biofilm reactor at 20 ± 2 °C up to 96-h and characterized for: a) attachment strength by enumerating cells after rinsing; b) hydrophobicity and interfacial tension by contact angle measurements; c) biofilm architecture by Laser Scanning Confocal Microscopy. All experiments were done in triplicate. Material, incubation, and solvent significantly affected the hydrophobicity and wetting properties of L. monocytogenes biofilms (P < 0.05). The type of material and incubation time significantly influenced hydrophobicity and wetting properties of L. monocytogenes biofilms (P < 0.05). Highest contact angle and lowest interfacial tension were observed on polycarbonate coupons. The data presented contributes to understanding Listeria biofilms grow on different surfaces commonly used in produce harvesting and storage. The data obtained in this study can be used when evaluating intervention strategies to control this pathogen in food premises. • L. monocytogenes biofilms are a challenge for food safety. • This study highlights the importance of considering surface characteristics. • Biofilms present different hydrophobicity property depending on the surface. • This information should be considered when selecting cleaning and sanitizers. [ABSTRACT FROM AUTHOR]

SUMO adducts occur in Aspergillus flavus , and are implicated in fungal biology, while the underlying mechanism and the SUMOylation apparatus components in this saprophytic food spoilage mould, remain undefined. Herein, genes encoding SUMOylation cascade enzymes in A. flavus , including two heterodimeric SUMO E1 activating enzymes, a unique SUMO E2 conjugating enzyme, and one of SUMO E3 ligases, were identified and functionally analyzed. Global SUMO adducts immunoassay, multiple morphological comparison, aflatoxin attributes test, fungal infection and transcriptomic analyses collectively revealed that: E1 and E2 were essential for intracellular SUMOylation, and contributed to both stress response and fungal virulence-related events, including sporulation, colonization, aflatoxins biosynthesis; the primary E3 in this fungus, AfSizA, might serve as the molecular linkage of SUMOylation pathway to fungal virulence rather than SUMOylation-mediated stress adaptation. These findings demonstrated that SUMOylation machinery in A. flavus was functionally intact and contributed to multiple pathobiological processes, hence offering ideas and targets to control food contamination by this mycotoxigenic fungus. [Display omitted] • A functionally intact SUMOylation machinery in A. flavus was identified. • Unique E1 and E2 contributed to fungal virulence as well as stress response. • The primary E3, AfSizA transferred the majority of SUMO from sole E1-E2 cascade. • Fungal virulence may molecularly converge with SUMOylation machinery at AfSizA. [ABSTRACT FROM AUTHOR]

Salmonella is a food-borne zoonotic pathogen that threatens food safety and public health security. Temperate phages can influence bacterial virulence and phenotype and play an important role in bacterial evolution. However, most studies on Salmonella temperate phages focus on prophage induced by bacteria, with few reports on Salmonella temperate phages isolated in the environment. Moreover, whether temperate phages drive bacterial virulence and biofilm formation in food and animal models remains unknown. In this study, Salmonella temperate phage vB_Sal_PHB48 was isolated from sewage. TEM and phylogenetic analysis indicated that phage PHB48 belongs to the Myoviridae family. Additionally, Salmonella Typhimurium integrating PHB48 was screened and designated as Sal013+. Whole genome sequencing revealed that the integration site was specific and we confirmed that the integration of PHB48 did not change the O-antigen and coding sequences of Sal013. Our in vitro and in vivo studies showed that the integration of PHB48 could significantly enhance the virulence and biofilm formation of S. Typhimurium. More importantly, the integration of PHB48 significantly improved the colonization and contamination ability of bacteria in food samples. In conclusion, we isolated Salmonella temperate phage directly from the environment and systematically clarified that PHB48 enhanced the virulence and biofilm-forming ability of Salmonella. In addition, we found that PHB48 increased the colonization and contamination ability of Salmonella in food samples. These results indicated that the highly pathogenic Salmonella induced by temperate phage was more harmful to food matrices and public health security. Our results could enhance the understanding of the evolutionary relationship between bacteriophages and bacteria, and raise public awareness of large-scale outbreaks resulting from Salmonella virulence enhancement in food industry. • Salmonella temperate phage vB_Sal_PHB48 was directly isolated from the sewage. • We screened S. Typhimurium integrated PHB48 and determined the integration site. • Integration of PHB48 enhanced virulence and biofilm-forming ability of Sal013+. • PHB48 enhanced the colonization and contamination ability of Sal013+ on food. [ABSTRACT FROM AUTHOR]

Ultrasound technology has been focused on due to its unique advantages in biofilm removal compared with traditional antibacterial methods. Herein, the anti-biofilm properties of low-frequency ultrasound (LFUS) were studied against Enterohemorrhagic Escherichia coli O157: H7 (E. coli O157:H7). After ultrasonication (20 kHz, 300 W) for 5 min, the removal rate of biofilm from polystyrene sheets reached up to 99.999 %. However, the bacterial cells could not be inactivated completely even extending the duration of ultrasonic irradiation to 30 min. Fortunately, this study indicated that LFUS could efficiently weaken the metabolic capacity and biofilm-forming ability of bacterial cells separated from biofilm. It could be associated with the removal of cell surface appendages and damage to cell membrane induced by mechanical vibration and acoustic cavitation. Besides, the genetic analysis proved that the transcription level of genes involved in curli formation was significantly down-regulated during ultrasonic irradiation, thus impeding the process of irreversible adhesion and cells aggregation. Finally, the actual application effect of LFUS was also evaluated in different fresh produces model. The results of this study would provide a theoretical basis for the further application of ultrasound in the food preservation., Competing Interests: Declaration of competing interest No conflict of interest exists in the submission of this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Heat-resistant moulds (HRMs) are well known for their ability to survive pasteurization and spoil high-acid food products, which is of great concern for processors of fruit-based products worldwide. Whilst the majority of the studies on HRMs over the last decades have addressed their inactivation, few data are currently available regarding their contamination levels in fruit and fruit-based products. Thus, this study aimed to quantify and identify heat-resistant fungal ascospores from samples collected throughout the processing of pasteurized high-acid fruit products. In addition, an assessment on the effect of processing on the contamination levels of HRMs in these products was carried out. A total of 332 samples from 111 batches were analyzed from three processing plants (=three processing lines): strawberry puree (n = 88, Belgium), concentrated orange juice (n = 90, Brazil) and apple puree (n = 154, the Netherlands). HRMs were detected in 96.4% (107/111) of the batches and 59.3% (197/332) of the analyzed samples. HRMs were present in 90.9% of the samples from the strawberry puree processing line (1–215 ascospores/100 g), 46.7% of the samples from the orange juice processing line (1–200 ascospores/100 g) and 48.7% of samples from the apple puree processing line (1–84 ascospores/100 g). Despite the high occurrence, the majority (76.8%, 255/332) of the samples were either not contaminated or presented low levels of HRMs (<10 ascospores/100 g). For both strawberry puree and concentrated orange juice, processing had no statistically significant effect on the levels of HRMs ( p  > 0.05). On the contrary, a significant reduction ( p  < 0.05) in HRMs levels was observed during the processing of apple puree. Twelve species were identified belonging to four genera - Byssochlamys , Aspergillus with Neosartorya -type ascospores, Talaromyces and Rasamsonia . N. fumigata (23.6%), N. fischeri (19.1%) and B. nivea (5.5%) were the predominant species in pasteurized products. The quantitative data (contamination levels of HRMs) were fitted to exponential distributions and will ultimately be included as input to spoilage risk assessment models which would allow better control of the spoilage of heat treated fruit products caused by heat-resistant moulds. [ABSTRACT FROM AUTHOR]

A cluster of 34 human cases of listeriosis was traced to consumption of contaminated quargel cheese, a sour milk specialty sold in Austria, Germany and Czech Republic. Here, we try to assess how many portions were consumed by the Austrian population at a certain contamination level (CL). In total, 1623 cheese lots were produced during the outbreak period resulting in >3 million portions of cheese delivered to the market. From 650 sets of quality control data provided by the food business operator, we reconstructed the contamination scenario over time and identified 84 lots that were found to be positive. With regard to another sixteen lots, a CL was found ranging from one to 3,84 log 10  CFU L. monocytogenes /g, measured in product stored between one to 23 days after production. However the number of storage days at home before consumption is unknown. To resolve this issue, we modelled the theoretical CL of the product if consumed either 20, 30, 40 or 50 days post production. We found that 10 lots (approx. 27,350 portions) would have been contaminated at CLs higher than 3 log 10  CFU L. monocytogenes /g if all cheese had been consumed after 20 days of storage. This number shifts to 20 lots (approx. 54,700 portions) after 30 days of storage. If all cheese had been consumed at the end of shelf life (50 days of storage), theoretically 242,5 lots would have exceeded a CL of 6 log 10  CFU L. monocytogenes /g. We concluded that the extended shelf life given to the product was a driver of the outbreak scenario. It is stunning to note that so few cases were reported in spite of consumers' massive exposure to L. monocytogenes . We hypothesized that a low pathogenicity of both quargel outbreak clones (QOC1 and QOC2) could have contributed to this discrepancy. Our hypothesis was falsified since both strains QOC1 and QOC2 are fully virulent in an oral infection mouse model, showing even higher pathogenicity than the reference strain EGDe. [ABSTRACT FROM AUTHOR]

Next to applications in fermentations, Lactobacillus plantarum is recognized as a food spoilage organism, and its dispersal from biofilms in food processing environments might be implicated in contamination or recontamination of food products. This study provides new insights into biofilm development by L. plantarum WCFS1 through comparative analysis of wild type and mutants affected in cell surface composition, including mutants deficient in the production of Sortase A involved in the covalent attachment of 27 predicted surface proteins to the cell wall peptidoglycan (Δ srtA ) and mutants deficient in the production of capsular polysaccharides (CPS1–4, Δ cps1 – 4 ). Surface adhesion and biofilm formation studies revealed none of the imposed cell surface modifications to affect the initial attachment of cells to polystyrene while biofilm formation based on Crystal Violet (CV) staining was severely reduced in the Δ srtA mutant and significantly increased in mutants lacking the cps1 cluster, compared to the wild-type strain. Fluorescence microscopy analysis of biofilm samples pointed to a higher presence of extracellular DNA (eDNA) in cps1 mutants and this corresponded with increased autolysis activity. Subsequent studies using Δ acm2 and Δ lytA derivatives affected in lytic behaviour revealed reduced biofilm formation measured by CV staining, confirming the relevance of lysis for the build-up of the biofilm matrix with eDNA. [ABSTRACT FROM AUTHOR]

Salmonella enterica serovar Weltevreden is the most common non-typhoid Salmonella found in South and Southeast Asia. It causes zoonoses worldwide through the consumption of contaminated foods and seafood, and is considered as an important food-borne pathogen in China, especially in the Southern coastal area. We compared the whole genomes of 44 S . Weltevreden strains isolated from human stool and contaminated food samples from Southern Coastal China, in order to investigate their phylogenetic relationships and establish their genetic relatedness to known international strains. ResFinder analysis of the draft genomes of isolated strains detected antimicrobial resistance (AMR) genes in only eight isolates, equivalent to minimum inhibitory concentration assay, and only a few isolates showed resistance to tetracycline, ciprofloxacin or ampicillin. In silico MLST analysis revealed that 43 out of 44 S . Weltevreden strains belonged to sequence type 365 (CC205), the most common sequence type of the serovars. Phylogenetic analysis of the 44 domestic and 26 international isolates suggested that the population of S. Weltevreden could be segregated into six phylogenetic clusters. Cluster I included two strains from food and strains of the “ Island Cluster ”, indicating potential inter-transmission between different countries and regions through foods. The predominant S. Weltevreden isolates obtained from the samples from Southern coastal China were found to be phylogenetically related to strains from Southern East Asia, and formed clusters II–VI. The study has demonstrated that WGS-based analysis may be used to improve our understanding of the epidemiology of this bacterium as part of a food-borne disease surveillance program. The methods used are also more widely applicable to other geographical regions and areas and could therefore be useful for improving our understanding of the international spread of S. Weltevreden on a global scale. [ABSTRACT FROM AUTHOR]

The design of novel efficient antimicrobial peptides (AMPs) faces several issues, such as cost of synthesis, proteolytic stability or cytotoxicity. The identification of key determinants involved in the activity of AMPs, such as cationicity and amphipathicity, allowed the synthesis of short peptides with optimized properties. An ultrashort peptide made of the sequence H-Orn-Orn-Trp-Trp-NH2 (O3TR) showed antifungal activity against several contaminants from food products. This peptide inhibited the growth of the filamentous fungi Fusarium culmorum , Penicillium expansum and Aspergillus niger within a range of concentration of 12.5–50 μg/ml. In addition, O3TR inhibited the growth of the yeast Saccharomyces cerevisiae , Zygosaccharomyces bailii , Zygosaccharomyces rouxii , Debaryomyces hansenii and Kluyveromyces lactis within the range 12.5–50 μg/ml. A derivative peptide, called C12O3TR, made by the addition of lauric acid at the N-terminus of O3TR was 2- to 8-fold more active than O3TR against every species. In addition to the inhibition of conidial germination, O3TR and C12O3TR killed F. culmorum hyphae at 100 and 50 μg/ml respectively. The MIC of the two peptides against F. culmorum and Z. bailii after heat treatment at 100°C for 60 min and within the pH range 3–10, were not changed. However, the activity of O3TR against F.culmorum and Z. bailii was strongly reduced in salt solutions, whereas the lauric acid peptide kept its antifungal activity and resistance to proteolytic digestion. The conjugation with lauric acid reduced the random coiled structure and increased the α-helical content of O3TR. After conjugation with the dye tetramethylrhodamine (TMR), both peptides entered F. culmorum spores. They also both induced permeabilization of F. culmorum hyphae but only C12O3TR permeabilized Z. bailii membrane. In contrast to the lipopeptide, O3TR did not show haemolytic or cytotoxic activity when applied at the concentrations that exhibited antifungal potency. The two peptides were challenged against a yeast cocktail of S. cerevisiae and Z. bailii , and A. niger in different commercial beverages. After 7 days, O3TR was able to inhibit the yeast cocktail in a commercial lager and carbonated drink. Due to its antifungal potency, high stability and low cytotoxicity, the tetrapeptide could represent a promising starting point of a novel food preservative. [ABSTRACT FROM AUTHOR]

The aim of this research was to evaluate the feasibility of PCR-DGGE and Reverse Transcriptase-PCR-DGGE techniques for rapid detection of Vibrio species in foods. Primers GC567F and 680R were initially evaluated for amplifying DNA and cDNA of ten references Vibrio species by PCR method. The GC-clamp PCR amplicons were separated according to their sequences by the DGGE using 10% ( w / v ) polyacrylamide gel containing 45–70% urea and formamide denaturants. Two pair of Vibrio species, which could not be differentiated on the gel, was Vibrio fluvialis - Vibrio furnissii and Vibrio parahaemolyticus - Vibrio harveyi . To determine the detection limit, in the community of 10 reference strains containing the same viable population, distinct DNA bands of 3 species; Vibrio cholerae , Vibrio mimicus and Vibrio alginolyticus were consistently observed by PCR-DGGE technique. In fact, 5 species; Vibrio cholerae , Vibrio mimicus , Vibrio alginolyticus , Vibrio parahaemolyticus and Vibrio fluvialis consistently observed by Reverse Transcriptase-PCR-DGGE. In the community containing different viable population increasing from 10 2 to 10 5 CFU/mL, PCR-DGGE analysis only detected the two most prevalent species, while RT-PCR-DGGE detected the five most prevalent species. Therefore, Reverse Transcriptase-PCR-DGGE was also selected for detection of various Vibrio cell conditions, including viable cell (VC), injured cells from frozen cultures (IVC) and injured cells from frozen cultures with pre-enrichment (PIVC). It was found that cDNA band of all cell conditions gave the same migratory patterns, except that multiple cDNA bands of Plesiomonas shigelloides under IVC and PIVC conditions were found. When Reverse Transcriptase-PCR-DGGE was used for detecting Vibrio parahaemolyticus in the pathogen-spiked food samples, Vibrio parahaemolyticus could be detected in the spiked samples containing at least 10 2 CFU/g of this pathogen. The results obtained also corresponded to standard method (USFDA, 2004). In comparison with the detection of the Vibrio profiles in fourteen food samples using standard method, Reverse Transcriptase-PCR-DGGE resulted in 100%, 75% and 50% similarity in 3, 1 and 6 food samples, respectively. [ABSTRACT FROM AUTHOR]

This study focused on the use of antimicrobial edible coatings and films from micro-emulsions to reduce populations of foodborne pathogens in foods. Corn-Bio-fiber gum (C-BFG) was used as an emulsifier with chitosan. Allyl isothiocyanate (AIT) and lauric arginate ester (LAE) served as antimicrobials. Micro-emulsions were obtained from a solution consisting of 1% chitosan, 0.5% C-BFG, and 1–4% AIT or LAE which was subject to high pressure homogenization (HPH) processing at 138 MPa for 3 cycles. Coatings and films produced from the micro-emulsions had micro-pores with sizes ranging from 100 to 300 nm and micro-channels that hold antimicrobials effectively and facilitate the release of antimicrobials from the center to the surface of the films or coatings, thus enhancing their antimicrobial efficacy. The coatings and films with 1% AIT reduced populations of Listeria innocua by over 5, 2, and 3 log CFU in culture medium (Tryptic soy broth, TSB), ready-to-eat meat, and strawberries, respectively. The coatings and films with 1% LAE reduced populations of Escherichia coli O157:H7 and Salmonella spp. by over 5 and 2 log CFU in TSB and strawberries, respectively. This study provides an innovative approach for the development of effective antimicrobial materials to reduce food borne pathogenic contaminants on ready-to-eat meat, strawberries, or other food. [ABSTRACT FROM AUTHOR]

Salmonella survival was characterized and modeled during thermal dehydration of fresh garlic and storage of dehydrated garlic products. In our experiments that simulated commercial dehydration processing at 80 ± 5 °C, moderate level of Salmonella contamination (4–5 log CFU/g) on fresh garlic was reduced below the enumeration limit (1.7 log CFU/g) after 4.5 h of dehydration and not detectable by culture enrichment after 7 h. With high level of contamination (7–8 log CFU/g), the Salmonella population persisted at 3.6 log CFU/g after 8 h of processing. By increasing the dehydration temperature to 90 ± 5 °C, the moderate and high levels of initial Salmonella load on fresh garlic dropped below the enumeration limit after 1.5 and 3.75 h of processing and became undetectable by culture enrichment after 2.5 and 6 h, respectively. During the storage of dried garlic products, Salmonella was not able to grow under all tested combinations of temperature (25 and 35 °C) and water activity (0.56–0.98) levels, suggesting active inhibition. Storage temperature played a primary role in determining Salmonella survival on dehydrated garlic flakes. Under a typical storage condition at 25 °C and ambient relative humidity, Salmonella could persist over months with the population gradually declining (4.3 log reduction over 88 days). Granular size of dehydrated garlic had an impact on Salmonella survival, with better survival of the pathogen observed in bigger granules. At the early stage of dehydrated garlic storage (until 7 days), rising water activity appeared to initially promote but then inhibited Salmonella survival, resulting in a water activity threshold at 0.73 where Salmonella displayed strongest persistence. However, this phenomenon was less apparent during extended storage (after 14 days). [ABSTRACT FROM AUTHOR]

The efficacy of microwave-combined cold plasma treatment (MCPT) for inactivating Bacillus cereus spores contaminating red pepper ( Capsicum annum L.) flakes was investigated. The effects of red pepper drying method, particle size, and water activity (a w ) were also evaluated at two levels of microwave power (1700 and 2500 W/cm 2 ). The inactivation effect of MCPT was higher at higher microwave power. Spore reduction was more effective with vacuum-dried red pepper than far-infrared-dried flakes. A significantly higher level of spore reduction was observed with the red pepper sample with a smaller surface to volume ratio when one surface (exterior surface) was inoculated ( p < 0.05). Spore reduction by MCPT at high microwave power increased from 1.7 to 2.6 log spores/cm 2 when the a w of flake increased from 0.4 to 0.9 ( p < 0.05). MCPT did not change the color of red pepper flakes. MCPT demonstrated potential as a microbial decontaminating technology for red pepper flakes. [ABSTRACT FROM AUTHOR]

Staphylococcus argenteus is a novel species subdivided from Staphylococcus aureus . Whether this species can cause food poisoning outbreaks is unknown. This study aimed to investigate the enterotoxigenic activities of two food poisoning isolates suspected to be S. argenteus (Tokyo13064 and Tokyo13069). The results for phylogenic trees, constructed via whole genome sequencing, demonstrated that both isolates were more similar to a type strain of S. argenteus (MSHR1132) than any S. aureus strain. Moreover, the representative characteristics of S. argenteus were present in both strains, namely both isolates belong to the CC75 lineage and both lack a crtOPQMN operon. Thus, both were determined to be “ S. argenteus .” The compositions of the two isolates' accessory elements differed from those of MSHR1132. For example, the seb -related Staphylococcus aureus pathogenicity island, SaPIishikawa11, was detected in Tokyo13064 and Tokyo13069 but not in MSHR1132. Both isolates were suggested to belong to distinct lineages that branched off from MSHR1132 lineages in terms of accessory elements. Tokyo13064 and Tokyo13069 expressed high levels of s ( arg ) eb and produced S(arg)EB protein, indicating that both have the ability to cause food poisoning. Our findings suggest that S. argenteus harboring particular accessory elements can cause staphylococcal diseases such as food poisoning, similarly to S. aureus . [ABSTRACT FROM AUTHOR]

Despite continuing efforts to reduce foodborne pathogen contamination of fresh produce, significant outbreaks continue to occur. Identification of appropriate surrogates for foodborne pathogens facilitates relevant research to identify reservoirs and amplifiers of these contaminants in production and processing environments. Therefore, the objective of this study was to identify environmental Escherichia coli isolates from manures (poultry, swine and dairy) and surface water sources with properties similar to those of the produce associated foodborne pathogens E . coli O157:H7 and Salmonella enterica serotype Typhimurium. The most similar environmental E . coli isolates were from poultry ( n = 3) and surface water ( n = 1) sources. The best environmental E . coli surrogates had cell surface characteristics (zeta potential, hydrophobicity and exopolysaccharide composition) that were similar (i.e., within 15%) to those of S . Typhimurium and/or formed biofilms more often when grown in low nutrient media prepared from lettuce lysates (24%) than when grown on high nutrient broth (7%). The rate of attachment of environmental isolates to lettuce leaves was also similar to that of S . Typhimurium . In contrast, E . coli O157:H7, a commonly used E . coli quality control strain and swine isolates behaved similarly; all were in the lowest 10% of isolates for biofilm formation and leaf attachment. These data suggest that the environment may provide a valuable resource for selection of surrogates for foodborne pathogens. [ABSTRACT FROM AUTHOR]

Next generation sequencing (NGS) holds promise as a single application for both detection and sequence identification of foodborne viruses; however, technical challenges remain due to anticipated low quantities of virus in contaminated food. In this study, with a focus on data analysis using several bioinformatics tools, we applied NGS toward amplification-independent detection and identification of norovirus at low copy (< 10 3 copies) or within multiple strains from produce. Celery samples were inoculated with human norovirus (stool suspension) either as a single norovirus strain, a mixture of strains (GII.4 and GII.6), or a mixture of different species (hepatitis A virus and norovirus). Viral RNA isolation and recovery was confirmed by RT-qPCR, and optimized for library generation and sequencing without amplification using the Illumina MiSeq platform. Extracts containing either a single virus or a two-virus mixture were analyzed using two different analytic approaches to achieve virus detection and identification. First an overall assessment of viral genome coverage for samples varying in copy numbers (1.1 × 10 3 to 1.7 × 10 7 ) and genomic content (single or multiple strains in various ratios) was completed by reference-guided mapping. Not unexpectedly, this targeted approach to identification was successful in correctly mapping reads, thus identifying each virus contained in the inoculums even at low copy (estimated at 12 copies). For the second (metagenomic) approach, samples were treated as “unknowns” for data analyses using (i) a sequence-based alignment with a local database, (ii) an “in-house” k-mer tool, (iii) a commercially available metagenomics bioinformatic analysis platform cosmosID, and (iv) an open-source program Kraken. Of the four metagenomics tools applied in this study, only the local database alignment and in-house k-mer tool were successful in detecting norovirus (as well as HAV) at low copy (down to < 10 3 copies) and within a mixture of virus strains or species. The results of this investigation provide support for continued investigation into the development and integration of these analytical tools for identification and detection of foodborne viruses. [ABSTRACT FROM AUTHOR]

Blueberry have a short shelf life when fully ripe and susceptible to contamination of various pathogens. Our study investigated the effect of pulsed light (PL) on inactivation of Salmonella on blueberries and its impact on shelf-life, quality attributes and health-benefit compounds of blueberries. Dry PL (6 J/cm 2 ) and water-assisted PL (samples were agitated in water during PL treatment; 9 J/cm 2 ) along with two controls, dry control (untreated) and water-assisted control (water washing without PL), were applied to blueberries with subsequent storages at room temperature (3 days) or 5 °C (7 days). For Salmonella inactivation, dry PL treatment achieved 0.9 and 0.6 log reduction of Salmonella for spot and dip inoculation, respectively; while the water-assisted PL treatment reduced Salmonella by 4.4 log and 0.8 log for spot and dip inoculation, respectively. The water-assisted PL treatment resulted in Salmonella populations significantly lower than the dry control after storage regardless of the storage temperature and inoculation method. Neither dry nor water-assisted PL treatments improved the shelf life of blueberries even though direct inactivation of natural yeasts and molds were achieved. Surface lightness was instantly reduced after both dry and water-assisted PL treatments. Compared with the dry control, the two PL treatments did not reduce the firmness of blueberries. Weight loss was increased for the dry PL treated samples, but not for the water-assisted PL treatment for both storage conditions. Delayed anthocyanins accumulation and reduced total antioxidant activity were induced by both PL treatments at the end of storage at room temperature, while slight enhancement in total phenolics content was achieved by water-assisted PL treatment. In conclusion, the water-assisted PL treatment could effectively decontaminate Salmonella on blueberries while showed minimal or no impact on the shelf-life, quality attributes and health-benefit compounds of blueberries. PL processing parameters need to be further evaluated and optimized before possible application in the blueberry industry. [ABSTRACT FROM AUTHOR]

Kudoa septempunctata , a myxosporean parasite of the olive flounder ( Paralichthys olivaceus ), causes foodborne gastroenteritis after ingestion of contaminated raw flounder. Available methods to detect K . septempunctata require expensive equipment, well-trained personnel, and lengthy procedures. Here we generated a novel monoclonal antibody (MAb 15G11) against K. septempunctata and used it to produce a prototype immunochromatographic assay (prototype Kudoa-ICA). Within 15 min, the prototype Kudoa-ICA detected ≥ 1.0 × 10 5 spores/mL in a spore suspension and ≥ 2.0 × 10 4 spores/g of P. olivaceus muscle. The prototype Kudoa-ICA weakly cross-reacted with spores of K. lateolabracis and K. iwatai . cDNA sequence, expression, and western blot analyses revealed that MAb 15G11 detected an approximately 24-kDa protein encoded by a 573 bp mRNA. The cDNA nucleotide and predicted amino acid sequences were not significantly similar to any sequence in the GeneBank database. Immunoelectron microscopy revealed that MAb 15G11 reacted with the sporoplasmic cells and mainly with the capsulogenic cells of the K. septempunctata spore. Although the Kudoa-ICA was weakly cross-reactive with two other Kudoa species, it detected > 1.0 × 10 6 spores/g of K. septempunctata in P. olivaceus muscle, which is the criterion used to indicate a violation of the Food Hygiene Law of Japan. We conclude that MAb 15G11 may be suitable for use in an immunochromatographic assay for screening P. olivaceus muscle contaminated with K. septempunctata at food distribution sites such as food wholesalers, grocery stores, and restaurants. [ABSTRACT FROM AUTHOR]