Raw Pork Samples Research Articles

Surveillance of AMR in Escherichia ⁠coli on Raw Fresh Beef and Pork Meat in Retail Sale in Northern Ireland in 2023

• Mandatory anonymised reporting (without product details) under EU regulation 2020/1729 (https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Feur-lex.europa.eu%2Flegal-content%2FEN%2FTXT%2F%3Furi%3Duriserv%3AOJ.L_.2020.387.01.0008.01.ENG=05%7C02%7C%7C728e0578d2584889e4b308dcac7237a7%7C8a1c50f901b74c8aa6fa90eb906f18e9%7C0%7C0%7C638574853788123226%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C=KmvOFBnQh8Nlkib8E6S2hsMSMyJrJeQA%2FosdNhJvZtM%3D=0) for the monitoring and reporting of antimicrobial resistance (AMR) in zoonotic and commensal bacteria has been submitted to the EU for antimicrobial resistant Escherichia coli (E. coli) isolated from fresh pork and beef purchased for retail sale in NI from September to December 2023. • In this survey 96 pork and 98 beef fresh retail meat samples were tested for AMR E. coli according to EU guidelines. • No isolates were resistant to last line antibiotics, including colistin and carbapenems. • The prevalence of AMR E. coli was low (3%) from 194 raw fresh beef and pork samples. • The risk of acquiring AMR related infections through the handling and consumption of retail contaminated meats is very low, provided that good hygiene and cooking practices are followed when handling raw meats.

Ion coordination and chelation in Eu-MOFs matrices: Ultrafast fluorescence visual quantification monitoring of antibiotic residues

Rapid monitoring of trace antibiotics in the field in real time is essential for environment forewarning and human health. High sensitivity and real-time on-site quantitative monitoring of antibiotic residues can be accomplished by integrating portable sensors alongside fluorescent optics to construct an intelligent sensing platform that smoothly eliminates the instability of conventional detection methods. In this study, a ratiometric fluorescence sensor for the ultrasensitive detection of pefloxacin was built employing the photoinduced electron transfer (PET) mechanism from red Eu-MOFs to Mn2+-PEF complex. A visual color change results from the photoinduced electron transfer process from manganese ions to pefloxacin weakening the ligand metal charge transfer (LMCT) process in Eu-MOFs. This enables the ultrafast visible detection of pefloxacin and produces a transient shift in visual color with a detection limit as low as 15.4 nM. For the detection of pefloxacin in water, tomato, and raw pork samples, various sensing devices based on the developed fluorescent probes exhibit good practicability and accuracy. With the development of the ratiometric fluorescence sensing probe, it is now possible to quickly and quantitatively identify pefloxacin residues in the environment, offering a new method for ensuring the safety of food and people's health.

Development of a closed-tube, calcein-based loop-mediated isothermal amplification assay to detect Salmonella spp. in raw meat samples

Foodborne pathogens compromise food safety and public health, and Salmonella spp. are among the major pathogenic bacteria that cause outbreaks worldwide. Proper surveillance through timely and cost-effective detection methods across the food animal production chain is crucial to prevent Salmonella outbreaks and agricultural losses. Traditional culture methods are labor- and resource-intensive, with lengthy turnaround times. Meanwhile, conventional molecular tools, such as PCR and qPCR, are expensive and require technical skills and equipment. Loop-mediated isothermal amplification (LAMP) is a simple, rapid, inexpensive, highly sensitive, and specific molecular assay that does not require expensive equipment. Hence, this study developed and optimized a closed-tube, calcein-based LAMP assay to detect Salmonella using the invA gene and performed evaluation and validation against conventional PCR. The LAMP assay showed high specificity and sensitivity. It showed 10-fold higher sensitivity than conventional PCR, at <1 ng/μL DNA concentrations. Meanwhile, for CFU/mL, LAMP assay showed 1000-fold higher sensitivity than conventional PCR at 4.8 × 103 cells/mL than 4.8 × 107 cells/mL, respectively. For parallel testing of 341 raw meat samples, after conventional culture enrichment (until Rappaport-Vassiliadis broth), the optimized LAMP assay showed 100% detection on all samples while conventional PCR showed 100%, 99.04%, and 96.64% for raw chicken, beef, and pork samples, respectively. Meanwhile, a shortened enrichment protocol involving 3-h incubation in buffered peptone water only, showed lower accuracy in tandem with the optimized LAMP assay ranging from 55 to 75% positivity rates among samples. These suggest that the optimized LAMP assay possesses higher sensitivity over conventional PCR for invA gene detection when coupled with conventional enrichment culture methods. Hence, this assay has potential as a powerful complementary or alternative Salmonella detection method to increase surveillance capacity and protect consumer food safety and public health worldwide.

Development of triplex assay for simultaneous detection of Escherichia coli, methicillin resistant and sensitive Staphylococcus aureus in raw pork samples of retail markets.

Escherichia coli and Staphylococcus aureus are the most important food borne pathogen transmitting from animal meat and meat products. Therefore, it is vital to design an accurate and specific diagnostic tool for identifying those food-borne pathogens in animal meat and meat products. In the current study, E. coli, methicillin-resistant and sensitive S. aureus (MRSA and MSSA) were simultaneously detected using a developed triplex PCR-based technique. To obtain an optimal reaction parameter, the multiplex assay was optimised by changing just one parameter while holding the others constant. Specificity of the assay was assessed using several porcine bacterial template DNA. The plasmid DNA was used to test the multiplex PCR assay's sensitivity and interference in spiked pork samples. E. coli, MRSA, and MSSA each have PCR amplified products with sizes of 335, 533, and 209bp, respectively. The assay detects a minimum microbial load of 102CFU/μl for all the three pathogens and can identify bacterial DNA as low as 10-2ng/µl. The assay was validated employing 210 pork samples obtained from retail meat shops and slaughter houses, with MRSA, E. coli, and MSSA with the occurrence rate of 1.9%, 42.38%, and 18.1%, respectively. The rate of mixed bacterial contamination in pork meat samples examined with the developed method was 6.19%, 1.43%, 1.90%, and 1.43% for MSSA & E. coli, MRSA & E. coli, MSSA & MRSA, and E. coli, MSSA & MRSA, respectively. The developed multiplex PCR assay is quick and efficient, and it can distinguish between different bacterial pathogens in a single reaction tube.

How volatile composition facilitates olfactory discrimination of fat content in beef and pork

Foods differing in fat content can be distinguished through olfaction alone. The mechanisms underlying the ability of humans to discriminate between foods differing in fat content through olfaction are underexplored. In this study, beef and pork samples were prepared (raw and roasted) with low (muscle tissue; raw: 2–5%; roasted: 5%), medium (muscle tissue with lard; raw: 25–30%; roasted: 36–44%), and high (lard; raw: 40–42%; roasted: 69–70%) fat content. Olfactory triangle discrimination tests and ranking tests were performed to explore whether humans can discriminate and rank fat content of the samples through orthonasal olfaction. Headspace-Solid Phase Micro Extraction-Gas Chromatography-Mass Spectrometry (SPME-GC–MS) was used to characterize the volatile compound composition of the headspace of samples differing in fat content. Partial least-squares regression and partial least squares-discriminant analysis were performed to determine the volatile compounds that were responsible for olfactory fat content discrimination. We found that fat content in both raw and roasted samples can be distinguished through orthonasal olfaction. Perceived odor differences did not always contribute to olfactory identification of fat content. Roasted beef and pork meats with higher fat content had more abundant fatty acids, aldehydes, and ketones. Phthalic acid, isobutyl 2-ropylpentyl ester, and carbon disulfide facilitated the olfactory discrimination of fat content in raw pork and beef samples. 2-Methyl-propanal, benzaldehyde, 1-hydroxy-2-propanone, 2,3-pentanedione, 2,5-octanedione, and 2-butanone contributed to odor differences of roasted beef samples differing in fat content. We conclude that beef and pork samples differing in fat content differ in volatile compound composition of the headspace, and that these differences facilitate discrimination between samples differing in fat content based on olfaction alone.

Differences in Bacterial Communities of Retail Raw Pork in Different Market Types in Hangzhou, China.

Pork is widely consumed globally, and pigs' microbiota can potentially harbor foodborne pathogens. Contaminated pork in retail markets poses significant implications for food quality and safety. However, limited studies have compared pork microbiomes in various marketing environments. In this study, we utilized traditional microbial culture methods and high-throughput 16S rRNA sequencing to assess pathogen contamination and bacterial diversity in raw pork samples purchased from farmers' markets and two types of supermarkets (upscale and ordinary) in Hangzhou, China. Traditional microbial plate cultures identified E. coli and Salmonella spp. in 32.1% (27/84) and 15.5% (13/84) of the collected pork samples, respectively. Moreover, 12 out of 13 Salmonella strains were found in farmers' markets. The MIC results indicated a high prevalence of MDR strains, accounting for 51.9% in E. coli and 53.8% in Salmonella. The prevalence of NaClO tolerant strains was 33.3% and 92.3% for E. coli and Salmonella, respectively. Sequencing results indicated significantly higher microbial diversity in farmers' market samples compared to supermarket samples. Farmers' market pork samples exhibited a greater abundance of Acinetobacter, while Pseudomonas and Brochothrix were predominant in supermarket samples. The total abundance of pathogenic and spoilage bacteria was also higher for the farmers' market samples. Cross-contamination during market trading was evident through a high correlation between bacterial abundance in pork from different stalls within the same farmers' market. PICRUSt2 analysis identified significant differences in the average proportions of genes for carbohydrate, energy, and lipid metabolism from the farmers' markets, suggesting an exacerbation of microbial metabolic activity and increased perishability of pork in this environment. In conclusion, this study revealed variations in the characteristics of raw pork bacterial contamination across different types of retail stores, as well as differences in the composition and diversity of their respective bacterial communities.

1H NMR spectroscopy combined with multivariate data analysis for authentication of “Swabian–Hall Quality Pork” with protected geographical indication

1H NMR spectroscopy was applied to analyse samples of “Swabian–Hall Quality Pork” with protected geographical indication (PGI). To obtain maximum chemical information sample preparation was based on both polar extraction and non-polar extraction. A non-targeted approach was used to analyse the 1H NMR data followed by principal component analysis (PCA), linear discriminant analysis (LDA), and cross-validation (CV) embedded in a Monte Carlo (MC) resampling approach. A total of 275 raw pork samples were collected in the years 2018 to 2021. The correct prediction rate of “Swabian–Hall Quality Pork” was about 92% on average for both models based on either the polar or non-polar metabolites. In addition, 1H NMR data describing the polar and non-polar metabolites were combined in a classification model to improve the prediction accuracy. By performing a mid-level data fusion, a correct prediction rate of 98% was achieved. Furthermore, spectral regions in the NMR spectra of the polar and non-polar metabolites that are relevant for the classification of the pork samples were identified to describe potential chemical marker compounds.

Integration of Non-targeted Proteomics Mass Spectrometry with Machine Learning for Screening Cooked Beef Adulterated Samples

The degradation of ingredients in heat-processed meat products makes their authentication challenging. In this study, protein profiles of raw beef, chicken, duck, pork, and binary simulated adulterated beef samples (chicken-beef, duck-beef, and pork-beef) and their heat-processed samples were obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Heat-stable characteristic proteins were found by screening the overlapping characteristic protein ion peaks of the raw and corresponding heat-processed samples, which were discovered by partial least-squares discriminant analysis. Based on the 36 heat-stable characteristic proteins, qualitative classification for the raw and heat-processed meats was achieved by extreme gradient boosting. Moreover, quantitative analysis via partial least squares regression was applied to determine the adulteration ratio of the simulated adulterated beef samples. The validity of the approach was confirmed by a blind test with the mean accuracy of 97.4%. The limit of detection and limit of quantification of this method were determined to be 5 and 8%, respectively, showing its practical aspect for the beef authentication.

Investigation of Antibiotic Resistance in Fresh Beef, FreshPork, Fresh Chicken and Dairy Cow

Background: Chemical contamination in food has been a concern in public health both national and global levels. Contamination from pollution included air, water and soil, in meat from veterinary drugs used in animals, pesticides, food additives. Chemical residues in food are dangerous for health both short and long term. Commercial farming has grown, there are potential of using more drugs, especially antibiotics in farms. Objective: to study on antibiotic residues in fresh beef, fresh pork, fresh chicken and ready-to-drink dairy cow sold for consumers. Methods: A total of 36 samples which were 12 each of fresh meat, fresh pork and fresh chicken were tested by antibiotic residue detection kits from the Department of Medical Sciences, Thailand. These detection kits have 93% accuracy, 78.9% sensitivity, and 96.7% specificity. 72 samples of raw pork and chicken, which were advertised as organic, were tested for Tetracyclines, Macrolide, Aminoglycoside, Sulfonamide and Penicillins. Results: Tetracyclines, Macrolide, Aminoglycoside, Sulfonamide, Penicillins were detected in 12 samples of fresh beef, 12 samples of fresh pork, and 12 samples of fresh chicken. Tetracyclines were detected in 6 samples of dairy cow out of 43 samples. Conclusions: From 79 samples of fresh beef, fresh pork, fresh chicken and dairy cow, Tetracyclines, Macrolide, Aminoglycoside, Sulfonamide and Penicillin had been found in 100% of fresh beef samples, 100% of fresh pork, 100% of fresh chicken and 13.95 of dairy cow samples.

Detection of porcine DNA in food using direct asymmetric PCR and catalyzed hairpin assembly fluorescent biosensor: A novel assay for halal food analysis

Adulteration of halal-certified food with pork are often reported. Using direct PCR results in cost- and time-saving benefits, and allows flexibility in amplicon detection. Here, we aimed to develop and validate a novel, direct asymmetric PCR and catalyzed hairpin assembly fluorescent biosensor (daPCR-CHA-FB) with a portable LED lightbox for naked eye detection of porcine DNA in raw and processed food. We tested the assay's reproducibility, specificity, sensitivity, real-world applicability, and single-blind performance. Using only 1 mm3 samples, reproducibility test with 38 raw pork samples showed 2.6% false negative rate and 0.0% false positive rate. The lowest detection limits were 0.01 ng for porcine DNA and 0.1% for binary pork-and-beef mixture. No cross-reaction with 16 other species was observed. One-hundred market samples showed no false negative for pork-listed samples, while two samples declared as non-pork showed a positive reaction. The assay was simple, sensitive, specific, safe, and robust. It could be used by law enforcement agencies and small-scale laboratories to investigate contamination and adulteration of halal foods.

Research on quantitative method and contamination level of Salmonella enterica in raw pork from farmer's markets in Chengdu

To optimize the quantitative detection method for Salmonella enterica and analyze the quantitative contamination level of Salmonella enterica in raw pork samples from farmer's markets in Chengdu. Based on qualitative detection standard method of Salmonella enterica in China (GB 4789.4-2016) and the quantitative detection method of FSIS in the United States (MLG 4.08 and MLG appendix 2.05 MPN), the selective enrichment broth, screening plate, identification method and quantitative dilution ratio in quantitative detection of Salmonella enterica were optimized using 70 samples of raw pork. The optimized method compared by student's t-test was used to detect 40 samples of raw pork collected from farmer's markets in Chengdu from June to October 2020. For isolation of Salmonella from raw pork samples, the coincidence degree of TTB enrichment solution was significantly higher than that of RV enrichment solution (0.93±0.32 vs 0.35±0.62,t=8.324,P=0.001) and the consistency of suspicious colonies screened by XLT4 plate was significantly higher than that of Salmonella chromogenic medium (0.77±0.09 vs 1.00±0.00,t=2.971,P =0.017). The MPN method used 4 successive gradient dilutions, namely 12 tube method, could obtain more accurate quantitative value for Salmonella enterica. The combined use of selective enrichment broth TTB, XLT4 plate, Real-time PCR and MALDI-TOF mass spectrometry could get better results for screening and identifying Salmonella enterica. The detection rate for Salmonella enterica isolated from raw pork in farmer's markets was 92.5% (37/40). The most of the Salmonella positive samples (83.8%, 31/37) were detected with a contamination level ranged from 0.1 to 55 MPN/g. The optimized quantitative detection method for Salmonella enterica in raw pork in this study can effectively screen the target bacteria and obtain more accurate quantitative value.

Predictive Modeling of Thiol Changes in Raw Ground Pork as Affected by 13 Plant Extracts-Application of Arrhenius, Log-logistic and Artificial Neural Network Models.

In this study, predictive models of protein oxidation, expressed as the content of thiol groups (SH), in raw ground pork were established and their accuracy was compared. The SH changes were monitored during, maximum, 11 days of storage at five temperature levels: 4, 8, 12, 16, and 20 °C. The effect of 13 plant extracts, including spices such as allspice, black seed, cardamom, caraway, cloves, garlic, nutmeg, and onion, and herbs such as basil, bay leaf, oregano, rosemary, and thyme, on protein oxidation in pork was studied. The zero-order function was used to described SH changes with time. The effect of temperature was assessed by using Arrhenius and log–logistic equations. Artificial neural network (ANN) models were also developed. The results obtained showed very good acceptability of the models for the monitoring and prediction of protein oxidation in raw pork samples. High average R2 coefficients equal to 0.948, 0.957, and 0.944 were obtained for Arhhenius, log-logistic and ANN models, respectively. Multiple linear regression (MLR) was used to assess the influence of plant extracts on protein oxidation and showed oregano as the most potent antioxidant among the tested ones in raw ground pork.

Identification of Novel Sensitive and Reliable Serovar-Specific Targets for PCR Detection of Salmonella Serovars Hadar and Albany by Pan-Genome Analysis.

The accurate and rapid classification of Salmonella serovars is an essential focus for the identification of isolates involved in disease in humans and animals. The purpose of current research was to identify novel sensitive and reliable serovar-specific targets and to develop PCR method for Salmonella C2 serogroups (O:8 epitopes) in food samples to facilitate timely treatment. A total of 575 genomic sequences of 16 target serovars belonging to serogroup C2 and 150 genomic sequences of non-target serovars were analysed by pan-genome analysis. As a result, four and three specific genes were found for serovars Albany and Hadar, respectively. Primer sets for PCR targeting these serovar-specific genes were designed and evaluated based on their specificity; the results showed high specificity (100%). The sensitivity of the specific PCR was 2.8 × 101–103 CFU/mL and 2.3 × 103–104 CFU/mL for serovars Albany and Hadar, respectively, and the detection limits were 1.04 × 103–104 CFU/g and 1.16 × 104–105 CFU/g in artificially contaminated raw pork samples. Furthermore, the potential functions of these serovar-specific genes were analysed; all of the genes were functionally unknown, except for one specific serovar Albany gene known to be a encoded secreted protein and one specific gene for serovars Hadar and Albany that is a encoded membrane protein. Thus, these findings demonstrate that pan-genome analysis is a precious method for mining new high-quality serovar-targets for PCR assays or other molecular methods that are highly sensitive and can be used for rapid detection of Salmonella serovars.

Mining and evaluating novel serovar-specific Salmonella C1 serogroup genes by polymerase chain reaction analysis

Salmonella is a food-borne pathogen that causes worldwide infections in humans and animals. Over 2600 Salmonella serovars have been identified, and serogroup C1 (O:6, 7 epitopes) contains highly diverse serovars associated with high pathogenicity. Here, we aimed to develop a reliable polymerase chain reaction (PCR) method for detecting serovar-specific markers of Salmonella serogroup C1, with greater reliability and lower complexity than current methods. We identified three, two, four, and one novel genes unique to the Infantis, Rissen, Braenderup, and Virchow serovars. The PCR primers targeting these genes were specific for the target serovars. The detection limits of the PCR assays using 9 pairs of primers were 102–103 colony-forming units (CFUs)/mL and 104–105 CFU/g in pure bacterial cultures and artificially contaminated raw pork samples, respectively. No false-positive or false-negative results were obtained with 45 food samples, as determined by comparison with biochemical tests and traditional serotyping methods. The potential functions of all serovar-specific genes identified are unknown, except for one Rissen-specific gene that encodes a secreted protein. Our results imply that all 10 novel, specific genes can be considered as useful targets for detecting the Salmonella Infantis, Rissen, Braenderup, and Virchow serovars in food.

Survey of Intact and Nonintact Raw Pork Collected at Retail Stores in the Mid-Atlantic Region of the United States for the Seven Regulated Serogroups of Shiga Toxin–Producing Escherichia coli

A total of 514 raw pork samples (395 ground or nonintact and 119 intact samples) were purchased at retail stores in Pennsylvania, Delaware, and New Jersey between July and December 2017. All raw pork samples were screened for serogroup O26, O45, O103, O111, O121, O145, or O157:H7 cells of Shiga toxin-producing Escherichia coli (STEC-7) using standard microbiological and molecular methods. In short, 21 (5.3%) of the 395 ground or nonintact pork samples and 3 (3.4%) of the 119 intact pork samples tested positive via the BAX system real-time PCR assay for the stx and eae virulence genes and for the somatic O antigens for at least one of the STEC-7 serogroups. However, none of these 24 presumptive-positive pork samples subsequently yielded a viable isolate of STEC displaying a STEC-7 serogroup-specific surface antigen in combination with the stx and eae genes. These data suggest that cells of STEC serogroups O26, O45, O103, O111, O121, O145, or O157:H7 are not common in retail raw pork samples in the mid-Atlantic region of the United States.

Alternate antimicrobial resistance genes in multidrug resistant Salmonella spp. isolated from retail meats in Vietnam using RNA‐sequencing analysis

AbstractThe aim of this study was to examine the resistome characteristics of Salmonella spp. Contamination found in raw retail beef, pork, and chicken samples collected in Hanoi, Vietnam. Approximately 28% (25/90) of samples tested carried Salmonella bacteria. A total of 13/25 (52%) of these Salmonella bacteria were resistant to at least one antibiotic and 9/25 (36%) of the isolates were found to be multidrug resistant. RNA‐seq analysis detected the expression of 107 antibiotic resistance genes (e.g., 22 β‐lactam, 46 aminoglycosides, 8 quinolones, 7 chloramphenicol, 6 tetracycline, and 6 sulfonamide‐trimethoprim resistance genes, and 12 other antimicrobial resistance genes). The parC (S80R and novel mutations A628S) and gyrA (S83F and D87G) mutations contributed to ciprofloxacin resistance in Salmonella Indiana. The findings illustrate the significant potential for multiple‐antibiotic resistant Salmonella in raw retail meats from Hanoi markets, and also provide abundant data to better understand the multidrug resistant Salmonella resistome.Practical ApplicationsStudying the antibiotic resistance characteristics of Salmonella will provide important information for the prevention, control of diseases as well as food contamination control and regulations on the use of antibiotics in treatment and animal husbandry in order to limit antibiotic resistance of bacteria. Studying the expression genome of Salmonella, especially antibiotic resistance genes in multi‐antibiotic resistant Salmonella isolates, provides insight into the molecular epidemiology of antibiotic resistance genes. More importantly, it is possible to detect new mutations in antibiotic resistance genes that cause antibiotic resistance in Salmonella. In addition, studying the expression genome could help to identify new gene groups that can cause antibiotic resistance in this bacterium.

Detection of Hepatitis E Virus in Raw Pork and Pig Viscera As Food in Hebei Province of China.

Hepatitis E virus (HEV) is an important human pathogen with pigs serving as the main natural animal reservoir. In China, pork is the most popular meat, while pig viscera are also widely consumed. The aim of this study was to evaluate the prevalence of HEV among pigs at slaughter, and assess the presence of HEV in raw pork and pig viscera as food. Samples of pig blood, raw pork, liver, kidney, and blood curd were collected from slaughterhouse or (and) retail market. Anti-HEV antibody in serum samples was detected using enzyme-linked immunosorbent assay based on an ORF2 antigen sandwich kit. HEV RNA was tested by reverse transcription nested polymerase chain reaction (RT-nested PCR) and the viral load was further assessed using quantitative real-time PCR. The final amplicons of RT-nested PCR were sequenced and undergone phylogenetic analysis. Prevalence of antibodies to HEV was 90.4% (104/115) in pigs at slaughtered level, and one serum sample was HEV RNA positive (0.9%, 1/115). HEV RNA was detected in liver, kidney, and blood samples with positivity of 6.1% (7/114), 3.1% (4/129), and 1.2% (2/170) respectively with viral loads ranged 102.4-104.4 (2.4Log-4.4Log) genome equivalents per gram, but not in pork. The HEV RNA prevalence in both liver and kidney were statistically higher than in pork. Phylogenetic analysis showed that all obtained sequences belonged to HEV genotype 4, which were divided into subtypes 4a, 4b, 4d, and 4i, highly identical to the known human and swine HEV sequences in China. The results indicate that raw pig viscera are more likely to harbor HEV than pork, suggesting a higher transmission risk related to consuming pig organs.

Kimchi extracts as inhibitors of colour deterioration and lipid oxidation in raw groundpork meat during refrigerated storage.

Kimchi is a Korean, traditional fermented food made from Korean cabbage, radish, fermented jeotgal, ginger, garlic, and red pepper powder. It is a good source of natural antioxidants such as phenolic compounds, flavonoids, vitamins, and carotenoids. In this study, the antioxidant effects of various kimchi extracts on raw ground pork during refrigerated storage were investigated. Raw ground pork samples were treated with ascorbic acid, butylated hydroxyl toluene, baechu kimchi extract (BKE), gat kimchi extract (GKE), puchu kimchi extract (PKE), and white kimchi extract (WKE) and compared with raw ground pork without antioxidant treatment (NC). Increased metmyoglobin (MetMb), thiobarbituric acid reacting substance (TBARS), and total bacterial counts (TBC) were observed in all meat samples after storage, whereas pH, lightness, and redness values tended to decrease with increased storage time. All treated samples had lower TBARS and MetMb values and TBC compared to the control samples. Various kimchi ethanol extracts protected raw ground pork from lipid oxidation. The most potent antioxidant was GKE, whereas WKE was the weakest. This study suggests that the tested extracts, especially kimchi, have potential as natural preservatives to reduce colour degradation, lipid oxidation, and bacterial count in raw ground pork meat. © 2018 Society of Chemical Industry.

Contamination of Streptococcus suis in pork and edible pig organs in central Thailand.

Background and Aim:Streptococcus suis is an important zoonotic pathogen that can cause serious diseases in both swine and humans worldwide, especially in Asian countries. Since the majority of human cases reported in Thailand were infected by the consumption of a raw pork dish, the microbial food safety hazard associated with raw meat has been a matter of concern. Therefore, this study aimed to investigate the contamination by S. suis in pork and edible pig organs sold in central Thailand.Materials and Methods:In total, 88 raw pork and pig organ samples were purchased from markets, butcher shops, and supermarkets in central Thailand. The samples were examined using the loop-mediated isothermal amplification (LAMP) technique. LAMP reactions used for the detection of the DNA of S. suis (LAMPSS) and S. suis serotype 2 or 1/2 (LAMPSS2) were carried out according to previous studies.Results:The percentage of LAMPSS-positive samples was as high as 85.23% (75/88) while the percentage of LAMPSS2-positive samples was 17.05% (15/88). The percentages of LAMPSS- and LAMPSS2-positive samples were relatively high in both pig organs (lung and heart) and meat (sliced pork and minced pork) compared with the previous report. Except one supermarket, LAMPSS-positive samples were found in all sources investigated in this study. The pork and pig organs obtained from the markets and the butcher shops additionally gave positive results for LAMPSS2.Conclusion:Using LAMP techniques, high rate contamination of S. suis was found in raw pork and edible pig organs sold at different sources in central Thailand. The cross-contamination could have occurred through slaughtering, meat cutting, and meat handling processes. Therefore, consumers and people involved in the pig production industry should be aware of the potential hazards of S. suis infection; food safety education is crucial to prevent further infection.

Antibiotic resistance is lower in Staphylococcus aureus isolated from antibiotic-free raw meat as compared to conventional raw meat.

The frequent use of antibiotics contributes to antibiotic resistance in bacteria, resulting in an increase in infections that are difficult to treat. Livestock are commonly administered antibiotics in their feed, but there is current interest in raising animals that are only administered antibiotics during active infections. Staphylococcus aureus (SA) is a common pathogen of both humans and livestock raised for human consumption. SA has achieved high levels of antibiotic resistance, but the origins and locations of resistance selection are poorly understood. We determined the prevalence of SA and MRSA in conventional and antibiotic-free (AF) meat products, and also measured rates of antibiotic resistance in these isolates. We isolated SA from raw conventional turkey, chicken, beef, and pork samples and also from AF chicken and turkey samples. We found that SA contamination was common, with an overall prevalence of 22.6% (range of 2.8–30.8%) in conventional meats and 13.0% (range of 12.5–13.2%) in AF poultry meats. MRSA was isolated from 15.7% of conventional raw meats (range of 2.8–20.4%) but not from AF-free meats. The degree of antibiotic resistance in conventional poultry products was significantly higher vs AF poultry products for a number of different antibiotics, and while multi-drug resistant strains were relatively common in conventional meats none were detected in AF meats. The use of antibiotics in livestock contributes to high levels of antibiotic resistance in SA found in meat products. Our results support the use of AF conditions for livestock in order to prevent antibiotic resistance development in SA.