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During the primary pork processing at the stage of cooling half-carcasses, their mass is lost, leading to economic losses. One promising way to solve this problem is to wash half-carcasses with chilled water. This requires decontaminating meat with microflora, which causes its spoilage. The purpose of the study is to determine the effectiveness of the final treatment of pork half-carcasses with ferment cultures of SafePro® B-SF-443 (Leuconostoc carnosum) and SafePro® B-2 (Lactobacillus sakei) strains for their bioconservation and preservation of freshness. The paper uses organoleptic, chemical, and microbiological research methods. It was established that cooling half-carcasses of pork in the refrigerator using cold water washing contributes to the appearance of signs of meat spoilage in terms of microbial contamination and pH value already on the 4th day of storage. Surface treatment of half-carcasses with suspensions of lactic acid microorganisms of SafePro® B-SF-43 (Leuconostoc carnosum) and SafePro® B-2 (Lactobacillus sakei) strains at a dose of 107/cm² provides proper organoleptic parameters and the pH value of pork up to 7 days of storage, which correspond to high-quality meat. Both ferment cultures of lactic acid microorganisms reduce microbial contamination of meat due to the number of mesophilic aerobic and facultative anaerobic microorganisms in paired carcasses by 1.25 and 0.65 lg CFU/cm² and increase the number of lactic acid microorganisms by 3.47 and 3.43 lg CFU/cm² accordingly, this allows extending the shelf life of meat in the chilled form to at least 7 days. The most suitable culture for the final processing of half-carcasses of pork, which are cooled in the refrigerator in combination with washing with chilled water, is the SafePro® B-2 (Lactobacillus sakei) strain. The results obtained are promising for improving the technology of primary pork processing at the cooling stage using ferment cultures of lactic acid microorganisms as natural preservatives, which will increase the shelf life of meat, considering its quality and safety [ABSTRACT FROM AUTHOR]

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Abstract The aim of study was to evaluate the effect of high voltage dielectric barrier discharge (DBD) treatments on microbial and physicochemical quality of fresh pork in modified atmosphere packaging (MAP) during storage. Fresh pork loins were packaged in gas mixtures of 20:60:20, 40:40:20 or 60:20:20 (O 2 , N 2 , CO 2), and treated with high voltage DBD at 85 kV for 60 s and stored at 4 °C for 12 days. The data seems to suggest that the total viable counts were lower in treated groups only for days 4 and 8, and only significant on day 12 for the 60% MAP. The 60% MAP+DBD-treated group induced a higher TBARS and carbonyl values (P <.05) than 60% MAP group at 8 and 12 day. These results indicate that the in-package DBD system may be used to improve microbial quality of pork loin during storage. However, a method to overcome deteriorating effects by the treatment on fresh pork color and oxidation should be developed to guarantee consumer's acceptance. [ABSTRACT FROM AUTHOR]

The effect of high pressure processing (HPP) at 450 MPa for 10 min, enterocins A and B, thymol, and their combinations on the inactivation of a four-strain cocktail of Listeria monocytogenes and the properties of sliced dry-cured ham during 30 days at 4 and 12 °C was investigated. Enterocins A and B initially reduced L. monocytogenes levels by more than 2.5 log units, but a regrowth was recorded during the storage. Individual treatments of thymol and HPP exhibited a low antimicrobial effect against the pathogen. A synergistic antibacterial activity against L. monocytogenes was observed when HPP was combined with enterocins A and B, preventing the recovery of the pathogen during all the storage period. Such combined treatment also maintained total viable counts (TVC) at low levels after 30 days at 4 and 12 °C. Minor changes were detected in pH, aw, color parameters, and shear strength values in dry-cured ham treated with enterocins A and B, thymol, HPP, and their combinations during the storage at both temperatures. Combination of HPP at 450 MPa for 10 min and enterocins A and B might be applied as a hurdle technology, since it reduced L. monocytogenes counts and spoilage bacteria, and slightly affected the characteristics of sliced dry-cured ham. [ABSTRACT FROM AUTHOR]

This study evaluated the influence of different factors on pork hams cooked by sous-vide method. The quality and structural and microbiological properties of the treated samples were compared with those of controls. Samples were subjected to treatment at different combinations of temperature (61 °C or 71 °C), time (45 or 90 min), and vacuum degree (98.81% or 96.58%). The control sample was air packaged and boiled for 45 min in boiling water. Temperature and vacuum degree affected quality properties, while the effect of time was limited. Samples cooked at 61 °C showed higher moisture content, redness, and pink color of the meat juice, whereas samples cooked at 71 °C showed higher cooking loss rate, lightness, and volatile basic nitrogen values. Texture analysis indicated tenderer meat for the treatment group than the control. No microbial growth was detected in any treatment groups. Meat cooked at 61 °C and 98.81% vacuum showed more spacious arrangement of meat fiber. [ABSTRACT FROM AUTHOR]

The effects of adding combinations of rosemary (R: 1500, 2000, 2500 ppm) and green tea (G: 100, 200, 300 ppm) extracts in combination with synthetic antioxidants on the physiochemical, microbial, and sensory characteristics of fresh pork sausage were evaluated. R and G improved ( P  < .05) oxidative stability as evidenced by lower TBARS. R2500 and G300 had fewer PPC than the control at d 7, 14, and 21 of storage. Consumer acceptability scores were greater ( P  < .05) in sausages with R and G when compared to the control, and the majority of the R and G treatments were liked by 98% of the respondents. Treatment combinations of at least R2000 and G200 were described by positive drivers of liking such as spice-complex, ginger, nutmeg, rosemary flavors and aromas and lower scores for descriptors such as rancid, fruity, and off-flavor/odor. This research demonstrates that rosemary and green tea extracts improved the keeping quality of fresh pork sausage under simulated retail display. [ABSTRACT FROM AUTHOR]

Livestock-associated Staphylococcus aureus colonization and/or infections exist in pigs and people in frequent contact with pigs. In this study, a total of 130 S. aureus isolates obtained from different stages of pork production were subjected to antimicrobial susceptibility, biofilm formation, as well as PCR screening to identify virulence genes, and the accessory gene regulator alleles (agr). Among all 130 S. aureus isolates, 109 (83.8%, 109/130) isolates were positive for agr. All swine farms isolates belonged to agr IV, whereas S. aureus isolated from slaughterhouse and retail indicated diverse agr types. All isolates exhibited biofilm formation ability, and raw meat isolates (belonging to agr I) exhibited a greater ability to form strong biofilms than swine farms isolates (belonging to agr IV). agr -positive isolates were associated with more virulence genes than agr -negative isolates. Most biofilm-producing isolates were positive for microbial surface component recognizing adhesive matrix molecule (MSCRAMM), capsule type and ica group genes. The results illustrate a significant association between the prevalence rate of MSCRAMM, capsule type and ica group genes among isolates producing weak, moderate and strong biofilms. The high prevalence of resistance to ciprofloxacin, gentamicin, tetracycline, clarithromycin, clindamycin, and trimethoprim-sulfamethoxazole were mainly observed in moderate and weak biofilm producers. Our findings indicate that S. aureus isolates from pork production displayed diverse molecular ecology. [ABSTRACT FROM AUTHOR]

The post-mortem accumulation of the heme biosynthesis metabolite zinc protoporphyrin IX (ZnPP) in porcine muscle is associated with both a meat-inherent and a bacterial enzymatic reaction during meat storage. To estimate the bacterial impact on ZnPP formation, meat and meat-like media were investigated by HPLC-FLD (and MALDI-TOF-MS) after inoculation with a representative microorganism ( P. fluorescens ). Results indicate the principal ability of meat-inherent bacteria to form ZnPP in meat extracts and meat-like media, but not on the meat muscle. Thus it was concluded that the ZnPP formation in meat is due to a meat-inherent enzymatic reaction induced by porcine ferrochelatase (FECH), while the bacterial (FECH) induced reaction seems to be not significant. [ABSTRACT FROM AUTHOR]

Abstract: Acidic and alkaline electrolyzed water (EW) were investigated for their bactericidal effects when sprayed on the surface of beef, chevon (goat meat), and pork inoculated with Escherichia coli K12. Inoculated meat samples were subjected to different treatment times ranging from 2 to 12 min and enumerated on tryptic soy agar to determine the effective log reductions of microbial populations. Acidic EW treated beef, chevon, and pork samples resulted in the highest log reductions of approximately 1.16 (4 min), 1.22 (12 min), and 1.30 log10 CFU/mL (10 min), respectively; and alkaline EW treatments resulted in 1.61, 0.96, and 1.52 log10 CFU/mL reductions at 12 min treatment, respectively. In general, no significant difference in bacterial reduction (p > .05) among the different types of meat was observed. Experimental data were used to fit two microbial reduction models. The Weibull model best described E. coli reduction from meat surfaces. Practical applications: Foodborne microorganisms are responsible for a large number of outbreaks and foodborne illnesses. Several conventional methods such as heat and chemicals have been used for many years to ensure the safety of food. Meat is the most consumed food as a source of protein. Since meat is usually marketed raw, chlorine‐based washing technologies are commonly preferred for surface decontamination. However, these technologies may leave some chemical residues in meat that might alter its color, flavor, and texture. Electrolyzed oxidizing water is an alternative nonthermal technology that has been used in recent years to improve the safety of food products. This study thus focuses on determining the efficacy of acidic and alkaline electrolyzed water in inactivating Escherichia coli on beef, chevon, and pork surfaces. [ABSTRACT FROM AUTHOR]

Detecting pork contamination is critical for halal food preparation. A fragment of species-specific DNA from swine mitochondrial genome was selected as a target, and two oligonucleotides complementary to the target were used as probes for pork identification. The probe-conjugated gold nanoparticles bound to the target DNA, leading to the aggregation of gold nanoparticles and thus causing the colour of the gold nanoparticles to change from red to blue. More than 0.1 μmol/L of DNA led to an obvious colour change, which was observed by naked eyes after dotting test solutions onto a thin layer chromatography (TLC) plate. Furthermore, 0.001–1 μmol/L of the target was semi-quantified by using a digital camera and image processing software. This colourimetric detection might be a promising technique for differentiation of pork from other animal meat products without using any sophisticated machines, and thus will be used for halal authentication. [ABSTRACT FROM AUTHOR]

In food technology applications, electronic noses have been used on the on-line control of different processes. In this study, assessment of shelf life of fresh pork meat that had been stored under refrigeration in aerobic conditions using an electronic nose pocket device was tried. The physicochemical, sensory, and microbiological parameters of white female pork tenderloin, stored at 4 °C for 7 days, were related to the response obtained with an electronic nose device (Food Sniffer®) (FS) to validate its possible use as a rapid method of determining the shelf life of meat. The response of the electronic nose device, qualitatively validated, was significantly correlated with some parameters as microbiological counts or sensory parameters; unfortunately, tight quantitative limits between FS response and some analytical results as biogenic amine content could not be related. [ABSTRACT FROM AUTHOR]

Recent news of many cases of adulteration of meats with pork has bolstered the need for a way to detect and quantify the unwanted contamination of pork in other meats. To address this need, Microbiologique, Inc. has produced a sandwich ELISA assay that can rapidly quantify the presence of pork in cooked horse, beef, chicken, goat, and lamb meats. We carried out a validation study and showed that this assay has an analytical sensitivity of 0.00014 and 0.00040% (w/v) for cooked and autoclaved pork, respectively, and an analytical range of quantitation of 0.05-3.2% (w/v) in the absence of other meats. The assay can measure pork contamination down to 0.1% (w/w) in the presence of cooked horse, beef, chicken, goat, and lamb meats. The assay is quick and can be completed in 1 h and 10 min. [ABSTRACT FROM AUTHOR]

Abstract: Grape seed extract (GSE) as a natural antioxidant and antimicrobial was applied in Chinese traditional smoke‐cured bacon during 2 months storage in a natural ventilating room to improve its food quality and safety. Effects of GSE on color, texture, pH, humidity, microbiological quality, lipid oxidation, and biogenic amine formation in smoke‐cured bacon were investigated. These results revealed that the growth of food spoilage and pathogenic bacteria, such as Enterobacteriaceae, was completely inhibited during storage. The uses of GSE advanced the redness and lightness of Chinese traditional smoke‐cured bacon. GSE application significantly retarded (p < .05) lipid oxidation valuated by formation of thiobarbituric acid reactive substances test (TBARS) and the TBARS value was reduced by 69.8% in GSE‐treated bacon compared to the control after 2 months storage. The levels of tyramine, cadaverine, and putrescine in GSE‐treated samples were significantly lower than that of the control (p < .05), showing a reduction of 30.7, 37.1 and 29.4%, respectively. Moreover, the levels of histamine were 11.4 and 43.2 mg/kg in GSE‐treated bacon and the control sample, respectively, showing that the GSE application contributed to histamine reduction in smoke‐cured bacon. These findings suggested that GSE could be applied in Chinese traditional smoke‐cured bacon during storage to improve its quality and safety. Practical applications: High levels of biogenic amine, lipid oxidation, and microbiological quality have been described in Chinese traditional smoke‐cured bacon during storage at room temperature 0–15 °C, which are major problems for public health and food safety. Thus, it is worthwhile to select favorable conditions to strict control biogenic amine accumulation, lipid oxidation, and microbiological quality in smoke‐cured bacon. In this study, in order to improve the food quality and safety of smoke‐cured bacon during storage, grape seed extract (GSE) as a natural antioxidant and antimicrobial was used to extend the shelf life of traditional Chinese smoke‐cured bacon during storage at room temperature for 2 months and effects of GSE on lipid oxidation, biogenic amine formation, and microbiological quality on smoke‐cured bacon were investigated. The GSE as a natural antioxidant and antimicrobial applied into smoke‐cured bacon during storage appears to be beneficial for food safety and quality improvement. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is a widespread zoonotic parasite with a high seroprevalence in the human population and the ability to infect almost all warm blooded animals. Humans can acquire toxoplasmosis from different transmission routes and food plays a critical role. Within the food category, meat is of utmost importance, as it may contain bradyzoites inside tissue cysts, which can potentially cause infection after ingestion if parasites are not inactivated through freezing or cooking before consumption. In Italy, the most commonly consumed meat-producing animal species are bovines and pigs. However, T . gondii prevalence and consumption habits for meat of these animal species are very different. There is debate within the scientific community concerning which of these animal species is the main source of meat-derived human toxoplasmosis. The aim of this work was to build a quantitative risk assessment model to estimate the yearly probability of acquiring toxoplasmosis infection due to consumption of bovine meat and pork (excluding cured products) in Italy, taking into account the different eating habits. The model was fitted with data obtained from the literature regarding: bradyzoite concentrations, portion size, dose-response relation, prevalence of T . gondii in bovines and swine, meat consumption and meat preparation habits. Alternative handling scenarios were considered. The model estimated the risk per year of acquiring T . gondii infection in Italy from bovine and swine meat to be 0.034% and 0.019%, respectively. Results suggest that, due to existing eating habits, bovine meat can be a not negligible source of toxoplasmosis in Italy. [ABSTRACT FROM AUTHOR]

Abstract: Three extracts from American cranberry pomace (Vaccinium macrocarpon) were prepared: water (w‐PACE), ethanol, and a water/ethanol. Extracts were examined in terms of bioactive components content and antimicrobial activity in relation to 18 strains of bacteria, and 3 strains of fungi. Extracts contained organic acids, flavonols, terpenes (ursolic acid), and stilbenes (resveratrol). Water and water/ethanol extracts demonstrated a broader spectrum of antibacterial activity on selected strains compared to ethanol extract. The inhibition of pathogens growth (Escherichia coli, Salmonella ser. Enteritidis, Listeria monocytogenes, and Staphylococcus aureus) was determined in minced pork containing 2.5% w‐PACE. The number of pathogens in samples stored at 4 °C for 6 days was examined. The results show a significant (p < .05) growth inhibition for all pathogens in the minced pork meat with cranberry extract, compared to the control sample. Our results suggest the possibility of the application of the water extract of cranberry pomace as natural preservatives. Practical applications: American cranberry pomace can be used to receive extracts of antibacterial activity. The low cost of water extract production from cranberry pomace contributes to its attractiveness as the natural preservative to protect minced pork against foodborne pathogens. [ABSTRACT FROM AUTHOR]

This study aimed at evaluating the effect of Oregano vulgaris extract supplementation of heavy pig diet on the microbiological, chemical-physical and sensory characteristics of Fabriano salami. Fabriano salamis were produced processing meat derived from pigs belonging to two dietary groups of 16 pigs each: CTRL group fed a commercial pelleted feed, and OR group fed the CTRL diet integrated with 0.2% of oregano extract. Ten salamis per group were collected at 0, 7, 20 and 45 days of ripening and analysed for total viable count, enumeration of Enterobacteriaceae, Enterococcus spp, coagulase negative and positive staphylococci, Lactobacillus spp., Lactococcus spp., presence of Salmonella spp. and Listeria monocytogens, pH, water activity (aw) and colour (CIE L*a*b* colour system). At the end of the ripening (day 45) chemical composition (AOAC, 1990), total antioxidant capacity (ORACFL), thiobarbituric reactive substances (TBARS), total phenolic content (TPC) (Folin-Ciocalteu method) and consumer tests were performed. The integration of oregano extract in pig diets did not interfere with the microbial evolution, chemical composition, pH and aw. After 20 days of ripening the OR salami were redder then CTRL samples, which were also yellower at the end of ripening. Furthermore, the diet has significantly improved the oxidative status, the polyphenolic content and antioxidant power in OR salami. The consumers gave a higher score to OR salami in informed condition. [ABSTRACT FROM AUTHOR]

The role and importance of pigs and pork as sources of zoonotic hepatitis E virus ( HEV) has been debated in Canada and abroad for over 20 years. To further investigate this question, we compiled data to populate a risk profile for HEV in pigs or pork in Canada. We organized the risk profile ( RP) using the headings prescribed for a foodborne microbial risk assessment and used research synthesis methods and inputs wherever possible in populating the fields of this RP. A scoping review of potential public health risks of HEV, and two Canadian field surveys sampling finisher pigs, and retail pork chops and pork livers, provided inputs to inform this RP. We calculated summary estimates of prevalence using the Comprehensive Meta-analysis 3 software, employing the method of moments. Overall, we found the incidence of sporadic locally acquired hepatitis E in Canada, compiled from peer-reviewed literature or from diagnosis at the National Microbiology Laboratory to be low relative to other non-endemic countries. In contrast, we found the prevalence of detection of HEV RNA in pigs and retail pork livers, to be comparable to that reported in the USA and Europe. We drafted risk categories (high/medium/low) for acquiring clinical hepatitis E from exposure to pigs or pork in Canada and hypothesize that the proportion of the Canadian population at high risk from either exposure is relatively small. [ABSTRACT FROM AUTHOR]

The aim of this study was to design a time-effective method comprising a short pre-enrichment step in a non-selective broth in combination with the TaqMan probe applied in the real-time polymerase chain reaction to detect Yersinia enterocolitica strains in raw pork meat. The method enabled to detect 1 colony forming unit per 25 mg of Yersinia enterocolitica in pork meat. The specificity and reliability of the method was not diminished by the company of microflora naturally present in meat. The method was found successful to detect pathogenic Yersinia enterocolitica strains in pork meat. It is advised to be used for assessing the microbial risk and for controlling the microbial quality of meat and meat products. [ABSTRACT FROM AUTHOR]

Aims: Bacteria are considered one of the major driving forces of the mammalian decomposition process and have only recently been recognised as forensic tools. At this point, little is known about their potential use as 'post-mortem clocks'. This study aimed to establish the proof of concept for using bacterial identification as post-mortem interval (PMI) indicators, using a multi-omics approach.Methods and Results: Pieces of pork were placed in the University's outdoor facility and surface swabs were taken at regular intervals up to 60 days. Terminal restriction fragment length polymorphism (T-RFLP) of the 16S rDNA was used to identify bacterial taxa. It succeeded in detecting two out of three key contributors involved in decomposition and represents the first study to reveal Vibrionaceae as abundant on decomposing pork. However, a high fraction of present bacterial taxa could not be identified by T-RFLP. Proteomic analyses were also performed at selected time points, and they partially succeeded in the identification of precise strains, subspecies and species of bacteria that colonized the body after different PMIs.Conclusion: T-RFLP is incapable of reliably and fully identifying bacterial taxa, whereas proteomics could help in the identification of specific strains of bacteria. Nevertheless, microbial identification by next generation sequencing might be used as PMI clock in future investigations and in conjunction with information provided by forensic entomologists.Significance and Impact Of the Study: To the best of our knowledge, this work represents the first attempt to find a cheaper and easily accessible, culture-independent alternative to high-throughput techniques to establish a 'microbial clock', in combination with proteomic strategies to address this issue. [ABSTRACT FROM AUTHOR]

Pork meat is estimated to be responsible for 10-20% of human salmonellosis cases in Europe. Control strategies at the farm could reduce contamination at the slaughterhouse. One of the targeted sectors of production is maternity, where sows could be Salmonella reservoirs. The aim of this study was to assess the dynamics of shedding of Salmonella in terms of variation in both shedding prevalence and strains excreted during gestation in Quebec's maternity sector. The evolution of the fecal microbiota of these sows during gestation was also assessed to detect bacterial populations associated with these variations. A total of 73 sows both at the beginning and the end of the gestation were randomly selected and their fecal matter was analyzed. Salmonella detection was conducted using a method that includes two selective enrichment media (MSRV and TBG). Nine isolates per positive samples were collected. Among the 73 sows tested, 27 were shedding Salmonella. Sows in the first third of their gestation shed Salmonella significantly more frequently (21/27) than those in the last third (6/46) (χ² P < 0.05). The shedding status of 19 of the sows that were previously sampled in the first third of their gestation was followed, this time in the last third of their gestation, which confirmed reduction of shedding. Using 16S rRNA gene sequencing and qPCR, significant differences between the fecal flora of sows at the beginning and the end of the gestation, shedding Salmonella or not and with different parity number were detected. Using MaAsLin, multiple OTUs were found to be associated with the time of gestation, the status of Salmonella excretion and parity number. Some of the identified taxa could be linked to the reduction of the shedding of Salmonella at the end of gestation. In this study, we showed that the level of Salmonella shedding was variable during gestation with significantly higher shedding at the beginning rather than at the end of gestation. We also observed for the first time a significant change in the microbiota during sow gestation and identified interesting taxa which could be linked to a reduced Salmonella shedding. [ABSTRACT FROM AUTHOR]

Non-typhoidal Salmonella spp. (hereafter referred to as Salmonella ) on beef and pork is an important cause of foodborne illness and death globally. A systematic review of the effectiveness of interventions to reduce Salmonella prevalence or concentration in beef and pork was undertaken. A broad search was conducted in Scopus and CAB abstracts. Each citation was appraised using screening tools tested a priori . Level 1 relevance screening excluded irrelevant citations; level 2 confirmed relevance and categorized studies. Data were then extracted, and intervention categories were descriptively summarized. Meta-analysis was performed to provide a summary estimate of treatment effect where two or more studies investigated the same intervention in comparable populations. The Grading of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to assess the confidence in the estimated measures of intervention effect for data subgroups. [ABSTRACT FROM AUTHOR]

The safety of ready-to-eat products such as cured pork loins must be guaranteed by the food industry. In the present study, the efficacy of the dry curing process of pork loins obtained from free-range pigs in the reduction of three of the most important foodborne pathogens is analysed. A total of 28 pork loin segments, with an average weight of 0.57 ± 0.12 kg, were divided into four groups with three being inoculated by immersion with 7 log CFU/ml of either Salmonella Typhimurium, Campylobacter coli or Listeria innocua and the last one inoculated by immersion with sterile medium (control group). The loin segments were treated with a seasoning mixture of curing agents and spices, packed in a synthetic sausage casing and cured for 64 days. Microbiological analysis, pH and water activity (a w ) were assessed at four stages. The values of pH and a w decreased with curing time as expected. S. Typhimurium and C. coli dropped significantly (3.28 and 2.14 log units, respectively), but limited reduction of L. innocua (0.84 log unit) was observed along the curing process. In our study, three factors were considered critical: the initial concentration of the bacteria, the progressive reduction of pH and the reduction of a w values. Our results encourage performing periodic analysis at different stages of the manufacturing of dry cured pork loins to ensure the absence of the three evaluated foodborne pathogens. [ABSTRACT FROM AUTHOR]

The antibacterial activity of thyme essential oil (TEO) was evaluated against four serovars of Salmonella ( S. Enteritidis, S. Typhimurium, S. Montevideo and S. Infantis), experimentally inoculated (10 6 CFU/g) in minced pork, which was treated with different concentrations of the TEO (0.3%, 0.6% and 0.9%) packaged under vacuum or MAP (30%O 2 /50%CO 2 /20% N 2 ) and stored at 3 ± 1 °C for 15 days. GC–MS analysis of the TEO was performed in order to determine composition, and the predominant constituent was thymol (50.48%), followed by p -cymene and linalool. The minimum inhibitory concentration was determined for each Salmonella serovar studied. Among the tested active compounds, thymol and carvacrol exhibited the greatest inhibitory effect followed by TEO, with minimum inhibitory concentrations of 320 to 640 μg/ml. S . Enteritidis was the most sensitive serovar. During the storage period, Salmonella counts in pork were reduced by 1.69–4.05 log CFU/g. The influence of TEO on Enterobacteriaceae , lactic acid bacteria and total viable count was determined in control mince with no added Salmonella . The most pronounced antibacterial effect was achieved by the combination MAP and 0.9% TEO. Although the antibacterial activities of all studied concentrations of TEO in pork were evident and significant ( P < 0.05), sensory analysis showed that 0.3% TEO was the most acceptable to trained panellists. [ABSTRACT FROM AUTHOR]

The study was aimed to characterize, and determine antibiogram of C. perfringens type A isolated from the feces of human and animal diarrhoeal cases, as well as healthy animals, meat of pigs and goats, gills and intestine of fish and samples from fish pond. A total of 460 samples, including human diarrhoeal cases (n = 130); diarrhoeal cases of pig (n = 52) and goat (n = 50); fecal samples from healthy pig (n = 50) and goat (n = 50); meat samples viz . pork meat (n = 52); goat meat (n = 50) and fish including their environmental sources (n = 26) were used for isolation and identification of C. perfringens type A. All the biochemically confirmed isolates were positive for species-specific 16S rRNA and cpa genes by PCR assays. Toxinotyping of C. perfringens type A isolates showed that overall prevalence of C. perfringens type A with only cpa + gene was 43.2%; with cpa + and cpb2 + genes was 45.4%; with cpa + and cpe + genes was 4.9%; however, with cpa + , cpb2 + and cpe + genes was 6.6%. Antimicrobial susceptibility testing revealed that 83.7% of isolates were resistant to three or more antibiotics. [ABSTRACT FROM AUTHOR]

This paper describes a simple method focused on detection of roasted pork patties prepared from meat that was spoiled mainly by Rahnella aquatilis . The method includes application of PCR with species-specific primers differentiating R. aquatilis from other meat-spoiling Enterobacteriaceae and an electronic nose (E-nose) based on ultra-fast gas chromatography (UFGC). The volatile compound profile of R. aquatilis after heat treatment was described and compared to the volatile compound profile of minced pork patties that were stored up to 8 days. The results demonstrated that decreased relative content of trimethylamine and propanal in addition to the presence of benzeneacetaldehyde in odour of patties was linked to R. aquatilis – induced product spoilage. [ABSTRACT FROM AUTHOR]

Pork-based cooked products, such as cooked hams, are economically valuable foods that are vulnerable to bacterial spoilage, even when applying cooling and modified atmosphere packaging (MAP). Besides a common presence of Brochothrix thermosphacta , their microbiota are usually dominated by lactic acid bacteria (LAB). Yet, the exact LAB species diversity can differ considerably among products. In this study, 42 sliced cooked pork samples were acquired from three different Belgian supermarkets to map their bacterial heterogeneity. The community compositions of the dominant bacterial species were established by analysing a total of 702 isolates from selective agar media by (GTG) 5 -PCR fingerprinting followed by gene sequencing. Most of the isolates belonged to the genera Carnobacterium , Lactobacillus , and Leuconostoc , with Leuconostoc carnosum and Leuconostoc gelidum subsp. gelidum being the most dominant members. The diversity of the dominant bacterial species varied when comparing samples from different production facilities and, in some cases, even within the same product types. Although LAB consistently dominated the microbiota of sliced cooked pork products in the Belgian market, results indicated that bacterial diversity needs to be addressed on the level of product composition and batch variation. Dedicated studies will be needed to substantiate potential links between such variability and microbial composition. For instance, the fact that higher levels of lactobacilli were associated with the presence of potassium lactate (E326) may be suggestive of selective pressure but needs to be validated, as this finding referred to a single product only. [ABSTRACT FROM AUTHOR]

In order to ascertain the contamination status of Salmonella from carcass, equipment, environment and the intestinal contents in a pig slaughterhouse in Huaian, China, we investigated the prevalence and characteristics of Salmonella isolates in one slaughterhouse. A total of 636 samples were collected; Salmonella was laboratory-confirmed from 154/441 (34.9%) carcass swab-samples, 13/57 (22.8%) pieces of equipment, 30/86 (34.9%) environmental samples and the intestinal contents of 19/52 (36.5%) animals. Salmonella was found to be at its highest and lowest frequency during splitting (55.9%) and flaming (17.2%) processes, respectively. All Salmonella isolates were characterized by serotyping, multilocus sequence typing (MLST) and 69 S . Derby isolates were analyzed using pulsed-field gel electrophoresis (PFGE). Four serovars ( S . Derby, S . Rissen, S . Typhimurium, and S . London) were shared from the four sources and predominant serovars were S . Derby and S . Rissen. MLST results indicated that ten different STs were distinguished, of which ST40 was identified as the most prominent ST. Moreover, ST40, ST469, ST34 and ST155 comprised Salmonella isolates obtained from carcass, equipment, the slaughterhouse environment and intestinal contents. PFGE results showed that 33 pulsotypes (PF1-PF33) were identified. PF21, PF25 and PF29 suggested that many isolates from carcass-swab samples at different slaughterhouse process points were of the same pulsotype which also partly comprised isolates from equipment, the environment and intestinal contents. The present study provides an insight into Salmonella distribution in a pig slaughterhouse and revealed that cross-contamination occurs frequently at different sites, which provides data support for proposing some interventions to control Salmonella . [ABSTRACT FROM AUTHOR]

Pork burgers were evaluated for physical-chemical characteristics, fatty acids profile, lipid oxidation, antioxidant capacity, microbiological growth and sensory evaluation during storage time of seven days at 4 °C as function of three formulations as only meat (control, B) and meat added with ginger powder at the percentage of 1 and 2% (BG1 and BG2). BG1 and BG2 were less redness than control ones with incremented yellow hue. These modifications in color parameters did not modify sensory characteristics of burgers. PUFA were incremented (both PUFAω3 and PUFAω6) by the addition of ginger. Furthermore, BG1 and BG2 burgers showed to be less sensitive to lipid oxidation and to possess an increase in antioxidant capacity. Microbial growth evaluation of total aerobic count and Pseudomonas spp. showed that ginger powder delayed in time the bacterial contamination. Results highlighted that the presence of ginger led to an enhanced shelf life and health characteristics of burgers (increasing peroxidisability, ratio hypocholesterolemic/hypercholesterolemic and ratio ω3/ω6; reducing atherogenicity and thrombogenicity). [ABSTRACT FROM AUTHOR]

This work aims to evaluate the synergetic antimicrobial effects of cold nitrogen plasma (CNP) and lemongrass oil against L. monocytogenes on pork loin. Their possible effects on the physicochemical properties of pork were investigated as well. Lemongrass oil displayed anticipant antibacterial activities against L. monocytogenes at high dose, which could damage the bacterial membrane, leading to the losses of intracellular constituents, including DNA, protein and ATP. Compared with control groups, the number of L. monocytogenes on pork samples was reduced by 2.80 log10 steps after synergy treatment of CNP (500 W, 120 s) and lemongrass oil (5 mg/mL, 30 min). With the assistance of CNP, the satisfactory antibacterial effect for L. monocytogenes on pork was achieved after treatment for low concentration of lemongrass oil. In addition, the potential impacts on sensory attributes of pork were also minimized via combined treatment. Practical applications Under low concentration, lemongrass oil achieved the desired antibacterial effect for L. monocytogenes on pork loin with the assistance of CNP. The potential impacts on sensory attributes of pork loin were minimized via synergetic treatment as well. The synergetic treatment provides a new way for application of plant essential oil in food preservation. [ABSTRACT FROM AUTHOR]

The rate of the rise of drug resistance among pathogens in China is the fastest in the world. However, the resistance patterns for Salmonella serovars remain unknown. This study aimed to describe the resistance patterns for Salmonella serovars and confirm possible associations between antibiotic resistance and genes in connection to serovars. Five Salmonella serotypes were identified, with S. typhi (41.67%), S. enteritidis (20.83%) and S. typhimurium (18.75%) being the three most common strains. The majority of the Salmonella strains (93.75%) were resistant to one or more antimicrobial compounds. Multidrug resistance was only found in Salmonella from chicken, whereas isolates from pork were only resistant to tetracycline. Eight of 11 resistance genes were detected. Eight Salmonella isolates could transfer resistance genes to the recipient strain. These results indicated that the Salmonella isolates were resistant to more than one type of antibiotic, and resistance could be transmitted to humans through animal-based foods. Practical applications Salmonella is one of the world's most important food-borne pathogens. This study investigated Salmonella and drug resistance in fresh chicken and pork from the market to describe the resistance patterns for Salmonella serovars. The majority of the Salmonella strains were resistant to one or more antimicrobial compounds. Some Salmonella isolates could transfer resistance genes to Escherichia coli. Therefore, this study has significant application value for understanding the security situation of animal food and strengthening surveillance of food-borne zoonotic pathogens along the food chain. [ABSTRACT FROM AUTHOR]

The effect of combined treatment with supercritical CO 2 (2000 psi, 35 °C for 2 h) and rosemary powder (2.5% and 5.0% (w/w)) on microbiological and physicochemical properties of ground pork stored at 4 °C was investigated. The changes in total viable count, pH, total volatile base nitrogen (TVB-N), lipid oxidation and instrumental color (CIE L ⁎ , a ⁎ , b ⁎ ) were analyzed during a week period of refrigerated storage. It was found that microbial populations were reduced by supercritical CO 2 treatment, with the more pronounced effect being achieved by combined treatment with supercritical CO 2 and 5.0 g rosemary powder/100 g meat. Supercritical CO 2 treatment for 2 h could accelerate lipid oxidation of ground pork during refrigerated storage, whereas combination with rosemary can significantly slow down the increase of oxidation rate. Combined treatment of supercritical CO 2 and rosemary significantly increased L ⁎ and b ⁎ values of the ground pork, while the a ⁎ , pH and TVB-N value were not affected as compared to the treatment with supercritical CO 2 alone. The results of this study indicate that combined treatment of supercritical CO 2 and rosemary may be useful in the meat industry to enhance the storage stability of ground pork treated with long time exposure of supercritical CO 2 during refrigerated storage. [ABSTRACT FROM AUTHOR]

Salmonella is an important foodborne pathogen and a serious threat to human health worldwide. This study was to reduce Salmonella and the spoilage bacteria on fresh chilled pork using bacteriophage, nisin, and potassium sorbate (PS) along with their combinations. Microbial, chemical, and sensory qualities of the fresh chilled pork (artificially contaminated with Salmonella 3 log CFU/g) treated with bacteriophage (9 log PFU/g), nisin (5000 IU/g), PS (2 mg/g) and their combinations were evaluated. The result showed that all the samples treated with phage could significantly ( P < 0.05) reduce Salmonella population on fresh chilled pork. The combination treatment of nisin, PS and phage (N-PS-P) could significantly lower total viable counts (TVC), TVB-N and TBARS of the chilled pork during the storage period. The TVC of sample treated by N-PS-P was reduced by 2.3 log CFU/g at 7th day. It was also found through the electronic nose detection that the N-PS-P treatment was able to significantly reduce odour and maintain good sensory of the chilled pork. Hence, the N-PS-P treatment extended the shelf life of fresh chilled pork up to 14 days. No adverse effect of the phage on the chilled pork was observed. In conclusion, this study suggests that the phage and its combination with nisin and PS have great potential to be used as a good preservative for fresh chilled pork. [ABSTRACT FROM AUTHOR]

Salmonella Derby is one of the most prevalent serovars in pork and the most common serotype isolated from infants and toddlers. However, Salmonella Derby is also poorly understood, so we used Multilocus sequence typing (MLST) and Clustered regularly interspaced short palindromic repeats (CRISPRs) to subtype 100 Salmonella Derby isolates from pig farms, pig slaughterhouses, retail markets and humans that were collected during different years in Yangzhou, Jiangsu Province, China, in respect to the transmission of clonal groups of the serovar along the food chain. MLST analysis showed that two sequence type (ST) patterns (ST40 and ST71) were shared, and ST40 was the most common sequence type among isolates from four different sources. CRISPRs typing identified 32 different Derby CRISPR types (DCTs); ST40 and ST71 strains had 21 and 11 DCTs respectively, demonstrating the distinctiveness of the CRISPR regions among the isolates from the four sources during a seven-year period. It demonstrated that Salmonella Derby clones persisted in the same places and spread along the pork production chain. Overall, 100 spacers were analysed, including 61 for CRISPR1 (18 new) and 39 for CRISPR2 (17 new). Interestingly, we also found that the spacer arrangements were distinct between ST40 and ST71 strains, except for strain 13-S1. This analysis revealed that CRISPR genes are highly polymorphic even in the same serotype, which could be tremendously useful for bacterial subtyping during molecular epidemiological investigations. [ABSTRACT FROM AUTHOR]

Salmonella is recognized as one of the most important foodborne bacteria and has wide health and socioeconomic impacts worldwide. Fresh pork meat is one of the main sources of Salmonella, and efficient and fast methods for detection are therefore necessary. Current methods for Salmonella detection in fresh meat usually include >16 h of culture enrichment, in a few cases <12 h, thus requiring at least two working shifts. Here, we report a rapid (<5 h) and high-throughput method for screening of Salmonella in samples from fresh pork meat, consisting of a 3-h enrichment in standard buffered peptone water and a real-time PCR-compatible sample preparation method based on filtration, centrifugation, and enzymatic digestion, followed by fast-cycling real-time PCR detection. The method was validated in an unpaired comparative study against the Nordic Committee on Food Analysis (NMKL) reference culture method 187. Pork meat samples (n = 140) were either artificially contaminated with Salmonella at 0, 1 to 10, or 10 to 100 CFU/25 g of meat or naturally contaminated. Cohen's kappa for the degree of agreement between the rapid method and the reference was 0.64, and the relative accuracy, sensitivity, and specificity for the rapid method were 81.4, 95.1, and 97.9%, respectively. The 50% limit of detections (LOD50s) were 8.8 CFU/25 g for the rapid method and 7.7 CFU/25 g for the reference method. Implementation of this method will enable faster release of Salmonella low-risk meat, providing savings for meat producers, and it will help contribute to improved food safety. [ABSTRACT FROM AUTHOR]

Contaminated pork is a significant source of foodborne Salmonella infections. Pork is contaminated at the slaughterhouse; however, the mechanisms driving Salmonella contamination of carcasses are still poorly understood. The aim of this study was to investigate whether the amount of Salmonella carried by slaughtered pigs in their guts has an influence on carcass contamination. On that account, we tested whether the number of carcasses contaminated during a slaughter day was associated with the prevalence of highly contaminated pigs (HCP: Salmonella caecal loads ≥ 3log/g), or with the prevalence of pigs that simply carry Salmonella spp. in their guts. Three hundred and six pigs were sampled in a slaughterhouse from Central Italy. Salmonella loads in the caecum and on the carcass of each pig were estimated by the most probable number (MPN) technique. The overall prevalence of Salmonella was 34.64% and 7.19% for the caeca and carcasses, respectively. S . Derby and Salmonella enterica 4,[5],12:i:– were the most frequently isolated serovars. The prevalence of HCP was 11.44%. We found a higher number of contaminated carcasses on days of high prevalence of HCP than on days of low prevalence of HCP ( p = 0.0011). Conversely, carcass contamination did not vary with the prevalence of pigs that simply carried Salmonella spp. in their guts ( p = 0.7970). Therefore, the prevalence of HCP, but not the prevalence of pigs carrying Salmonella spp., was related to carcass contamination. Taken together, these findings suggest that reduction of Salmonella loads in the guts of slaughtered pigs would result in fewer contaminated carcasses, and consequently, help to minimise the risk of human infection due to the consumption of contaminated pork. [ABSTRACT FROM AUTHOR]

We investigated the presence of ESBL and AmpC-producing Enterobacteriaceae isolated from 200 rectal swabs of healthy swine and 200 samples of ground pork. Phenotypic testing by using the double synergy differential test (DSDT) for ESBL/AmpC-positive strains was confirmed by PCR and DNA sequence analysis. The localization of beta-lactamase genes was established by conjugation experiments. ESBL and/or AmpC-producing Enterobacteriaceae was found in 52.2% (95/182) of the isolates collected from rectal swabs and 3% (3/100) of isolates obtained from ground pork samples. Polymerase chain reaction and sequencing confirmed the presence of blaTEM-20, blaTEM-34, blaTEM-52, blaCTX-M-1, blaSHV-12, blaTEM-1 +SHV-12, blaTEM-20 +SHV-12, blaCMY-2, blaTEM-1+ CMY-2, blaACC-1 and blaACC-2. The conjugation assays yielded positive results, denoting a plasmid localization of the genes. Practical Applications In this study, the prevalence of ESBL and AmpC-producing Enterobacteriaceae isolated from rectal swabs of healthy swine and samples of ground pork were determined. ESBL/AmpC-positive strains were confirmed by PCR and DNA sequence analysis. The most frequently isolated species was E.coli, among the most common variants detected TEM-type ESBL, TEM-52 was showed. These findings provide new information about the presence of ESBL/AmpC at the farm level and have important implications for assessments of risks of meat contamination during slaughter. [ABSTRACT FROM AUTHOR]

Microbiological limits are widely used in food processing as an aid to reduce the exposure to hazardousmicroorganisms for the consumers. However, in pork, the prevalence and concentrations of Salmonella are generally low and microbiological limits are not considered an efficient tool to support hygiene interventions. The objective of the present studywas to develop an approachwhich couldmake it possible to define potential risk-basedmicrobiological limits for an indicator, enterococci, in order to evaluate the risk frompotential growth of Salmonella. A positive correlation between the concentration of enterococci and the prevalence and concentration of Salmonellawas shown for 6640 pork samples taken at Danish cutting plants and retail butchers. The sampleswere collected in five different studies in 2001, 2002, 2010, 2011 and 2013. The observations that both Salmonella and enterococci are carried in the intestinal tract, contaminate pork by the same mechanisms and share similar growth characteristics (lag phase and maximum specific growth rate) at temperatures around 5-10 ?C, suggest a potential of enterococci to be used as an indicator of potential growth of Salmonella in pork. Elevated temperatures during processingwill lead to growth of both enterococci and, if present, also Salmonella. By combining the correlation between enterococci and Salmonellawith risk modelling, it is possible to predict the risk of salmonellosis based on the level of enterococci. The riskmodel used for this purpose includes the dose-response relationship for Salmonella and a reduction factor to account for preparation of the fresh pork. By use of the riskmodel, it was estimated that themajority of salmonellosis cases, caused by the consumption of pork in Denmark, is caused by the small fraction of pork products that has enterococci concentrations above 5 log CFU/g. This illustrates that our approach can be used to evaluate the potential effect of differentmicrobiological limits and therefore, the perspective of this novel approach is that it can be used for definition of a risk-basedmicrobiological limit for enterococci. The limit for enterococci can then be used for development of a process hygiene criterion in cutting plants and retail butcher shops, with the purpose of reducing the risk of Salmonella for the consumer. [ABSTRACT FROM AUTHOR]

The objective of this study was to directly construct a tertiary growth model for Listeria monocytogenes in a simulated comminuted, non-cured cooked pork product and simultaneously determine the kinetic parameters using a combination of dynamic and isothermal growth curves. Growth studies were conducted using a cocktail of 5 strains of L. monocytogenes in cooked pork under both dynamic and isothermal temperature profiles designed to examine the effect of temperature on bacterial growth. A direct kinetic analysis method was used to construct the growth models and determine the kinetic parameters. The bacterial growth was simulated by a set of differential equations, and the temperature effect was evaluated by the cardinal parameters model. A numerical analysis and optimization method was used to simultaneously solve the different equations and search for the best fits of kinetic parameters for the growth curves and models. The estimated minimum, optimum, and maximum growth temperatures were 0, 33.0, and 42.6 °C, matching well with typical growth characteristics of this microorganism. The root-mean-square error (RMSE) of curve-fitting was 0.42 log CFU/g. The growth models and kinetic parameters were validated using both independent dynamic and isothermal growth curves to check the accuracy of the models. The results showed that the RMSE of predicted growth was 0.49 log CFU/g. The residual errors of predictions follow a Laplace distribution, with 80.3% of the residual errors falling within ±0.5 log CFU/g of the observations. This study proves that the one-step dynamic analysis with both dynamic and isothermal temperature profiles can be an effective approach for simultaneously constructing a tertiary model and determining the kinetic parameters. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of the fast cooling process on the microbiological community in chilled fresh pork during storage. We established a culture-independent method to study viable microbes in raw pork. Tray-packaged fresh pork and chilled fresh pork were completely spoiled after 18 and 49 d in aseptic bags at 4 °C, respectively. 16S/18S ribosomal RNAs were reverse transcribed to cDNA to characterize the activity of viable bacteria/fungi in the 2 types of pork. Both cDNA and total DNA were analyzed by high-throughput sequencing, which revealed that viable Bacteroides sp. were the most active genus in rotten pork, although viable Myroides sp. and Pseudomonas sp. were also active. Moreover, viable fungi were only detected in chilled fresh pork. The sequencing results revealed that the fast cooling process could suppress the growth of microbes present initially in the raw meat to extend its shelf life. Our results also suggested that fungi associated with pork spoilage could not grow well in aseptic tray-packaged conditions. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a molecular predictive model from quantitative real-time polymerase chain reaction methods to describe the growth ofS. aureusstrains in artificially contaminated pork in storage dependent of a constant temperature (7–30°C). This model acquired by quantitative real-time polymerase chain reaction methods was compared to a conventional predictive model using data. This study used three of the main growth models to fit the growth equation. The results proved that Modified Gompertz, Logistic, and Richards models were adequate for describing the growth curves. These models had the very low rate of the growth ofS. aureusin pork during a lag phase. The growth rate increased with temperature, and the lag time decreased. Lag phases were apparent in all models, and those samples stored at low temperatures had longer lag phases. There was no significant difference in the molecular and conventional predictive models for any of the growth curves. However, the use of a molecular predictive model could save more time and labor to construct more precise models of certain pathogens. In conclusion, the molecular predictive model could provide an effective method to lessen the risk ofS. aureusof pork. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a major public health issue, due to the presence of Toxoplasma gondii , mainly in pork. The aim of this study was to determine the occurrence of T. gondii in pigs and wild boars bred in different production systems in the Czech Republic using ELISA and qPCR methods. Our results show that T. gondii infection is widespread in pigs and wild boars bred and slaughtered in the Czech Republic and that there is a higher exposure to T. gondii in backyard slaughter operations and organic pig farming, indicating a potential risk for meat consumption. Additionally, genotyping of amplified loci for Type II suggests the presence of one clonal genotype circulating in these animals. [ABSTRACT FROM AUTHOR]

In this study nine strains of Enterococcus faecalis and 12 strains of Enterococcus faecium , isolated from different sample types in the swine meat chain and previously characterized for the presence of antibiotic resistance genes, were examined for phenotypic tolerance to seven biocides (chlorexidine, benzalkonium chloride, triclosan, sodium hypochlorite, 2-propanol, formaldehyde and hydrogen peroxide) and resistance to nine antibiotics (ampicillin, vancomycin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline and chloramphenicol). Moreover, the presence of efflux system encoding genes qac A/B, qac C, qac E, qac EΔ1, eme A, and stress response genes, sig V and gsp 65, involved in the tolerance to biocides, was analysed. Most strains were not tolerant to the biocides, but showed minimum inhibitory concentrations (MICs) higher than the recommended cut-off values for all the antibiotics tested, except for vancomycin and chloramphenicol. Only weak correlations, if any, were found between biocide and antibiotic resistance data. One E. faecalis strain was tolerant to triclosan and one E. faecium strain, with higher tolerance to chlorexidine than the other strains tested, was found to carry a qacA/B gene. Our results indicated that phenotypic resistance to antibiotics is very frequent in enterococcal isolates from the swine meat chain, but phenotypic tolerance to biocides is not common. On the other hand, the gene qacA/B was found for the first time in the species E. faecium , an indication of the necessity to adopt measures suitable to control the spread of biocide resistance determinants among enterococci. [ABSTRACT FROM AUTHOR]

An electrochemical microdevice for measuring pork freshness was developed based on the value of measurement indicators— K , K i , and H . Four sensors were integrated to measure the sum of the concentrations appearing in the equations that define the K , K i , and H values. With standard solutions, the correlation coefficients for sensors 1–4 were 0.888, 0.979, 0.816, and 0.828, respectively. Each sensor could complete one measurement in 2 min. A good correlation was obtained between the K values measured by the proposed microdevice and by ultra-performance liquid chromatography. Based on the sensor responses obtained with real pork extract samples, the R 2 value between the K and K i values was 0.843, while that between the K and H values was only 0.807 during a 15-day storage period. [ABSTRACT FROM AUTHOR]

The potential of chitosan as a possible booster of the antimicrobial activity of Origanum vulgare EO (OEO) against spoilage bacteria and Listeria monocytogenes was investigated in fresh pork meat. Pork fillets were inoculated with 3 L. monocytogenes strains, dipped either in Origanum vulgare (oregano) Essential Oil (OEO) at 2 and 4%, or in chitosan 1% alone or added with 2 and 4% OEO, then packed under modified atmosphere (70% O 2 , 20% CO 2 , 10% N 2 ) and stored at 4 °C for 15 days. OEO did not reduce L. monocytogenes growth, while 2 Log decrease was obtained after 2 days of storage in treatments with chitosan alone or with OEO, with growth inhibition up to day 15 in samples with chitosan and OEO 4%. When OEO was combined with chitosan, total viable counts and spoilage bacteria were reduced and contained over time, particularly Pseudomonas (2.0 Log CFU/g at day 15) and Brochothrix thermosphacta (undetectable). All the treatments applied extended meat shelf-life with respect to control, whose commercial shelf-life was 10 days. Chitosan treatments enhanced L* and maintained a* values almost stable during storage. Chitosan and OEO singly applied reduced lipid oxidation (0.62–0.75 mg malondialdehyde/Kg meat) compared to control (0.99 mg malondialdehyde/Kg meat). Finally, chitosan treated samples were not recognized with respect to the control, whereas OEO gave bitter taste; chitosan with OEO instead mitigated the effect of OEO addition to meat. Chitosan combined with OEO boosts its antimicrobial activity and shows a potential for application in industrial production of fresh pork in MAP, to achieve shelf-life extension, control of L. monocytogenes growth, stability of color and protective effect from oxidation, with low sensory impact. [ABSTRACT FROM AUTHOR]

Salmonella carriage and cutaneous contamination of pigs at slaughter are a major risk for carcass contamination. They depend on Salmonella prevalence at farm, but also on transmission and skin soiling among pigs during their journey from farm to slaughterhouse. To better understand and potentially control what influences Salmonella transmission within a pig batch during this transport and lairage step, we proposed a compartmental, discrete-time and stochastic model. We calibrated the model using pork chain data from Brittany. We carried out a sensitivity analysis to evaluate the impact of the variability in management protocols and of the uncertainty in epidemiological parameters on three model outcomes: prevalence of infection, average cutaneous contamination and number of new infections at slaughter. Each outcome is mainly influenced by a single management factor: prevalence at slaughter mainly depends on the prevalence at farm, cutaneous contamination on the contamination of lairage pens and new infections on the total duration of transport and lairage. However, these results are strongly affected by the uncertainty in epidemiological parameters. Re-excretion of carriers due to stress does not have a major impact on the number of new infections. [ABSTRACT FROM AUTHOR]

The use of phenolic compounds derived from agricultural by-products could be considered as an eco-friendly strategy for food preservation. In this study a purified phenol extract from olive vegetation water (PEOVW) was explored as a potential bioactive ingredient for meat products using Italian fresh sausage as food model. The research was developed in two steps: first, an in vitro delineation of the extract antimicrobial activities was performed, then, the PEOVW was tested in the food model to investigate the possible application in food manufacturing. The in vitro tests showed that PEOVW clearly inhibits the growth of food-borne pathogens such as Listeria monocytogenes and Staphylococcus aureus . The major part of Gram-positive strains was inhibited at the low concentrations (0.375–3 mg/mL). In the production of raw sausages, two concentrates of PEOVW (L1: 0.075% and L2: 0.15%) were used taking into account both organoleptic traits and the bactericidal effects. A multivariate statistical approach allowed the definition of the microbial and physicochemical changes of sausages during the shelf life (14 days). In general, the inclusion of the L2 concentration reduced the growth of several microbial targets, especially Staphylococcus spp. and LABs (2 log 10 CFU/g reduction), while the increasing the growth of yeasts was observed. The reduction of microbial growth could be involved in the reduced lipolysis of raw sausages supplemented with PEOVW as highlighted by the lower amount of diacylglycerols. Moisture and a w had a significant effect on the variability of microbiological features, while food matrix (the sausages' environment) can mask the effects of PEOVW on other targets (e.g. Pseudomonas ). Moreover, the molecular identification of the main representative taxa collected during the experimentation allowed the evaluation of the effects of phenols on the selection of bacteria. Genetic data suggested a possible strain selection based on storage time and the addition of phenol compounds especially on LABs and Staphylococcus spp. The modulation effects on lipolysis and the reduction of several microbial targets in a naturally contaminated product indicates that PEOVW may be useful as an ingredient in fresh sausages for improving food safety and quality. [ABSTRACT FROM AUTHOR]

In this paper are given the results from the analysis of the influence of the garlic extract on the chemical composition, the microbiological status and the sensory characteristics of minced pork meat and the semi-durable sausage. In order to do the analysis, we prepared the following four groups of minced pork meat and sausage: group 1 – without a garlic extract, group 2 – with garlic extract of 0.1 g/kg, group 3 – with a garlic extract of 0.2 g/kg, and group 4 – with a garlic extract of 0.3 g/kg. We randomly chose nine samples for the analyzis. Not one of the analyzed groups of minced pork meat and semi-durable sausage showed the presence of Clostridia, Escherichia coli, Salmonella or Listeria monocytogenes. The presence of other bacteria mostly bacilli was confirmed. The largest number of bacteria was confirmed in the controlled groups, while the smallest number of bacteria was in the group with a garlic extract of 0.3 g/kg. The controlled groups of minced pork meat and semi-durable sausage got very little sensory marks, while the best marked were the groups with an extract of 0.3 g/kg. [ABSTRACT FROM AUTHOR]

The hurdle technology, which consists of combining different preservative techniques is an alternative way of preventing growth of spoilage microorganisms while keeping a high quality of flavor. The objective of the study was to enhance the quality of fresh minced pork meat with mixture of lactic acid (LA), natural antioxidant dihydroquercetin (DHQ) from Siberian larch (Larix sibirica Ledeb) and essential oil (EO) extract of thymol (TH), using combinations of different packaging (vacuum (VP), modified atmosphere (MAP) and aerobic packaging (AP)). In the course of the study the aerobic colony count (ACC), Escherichia coli, yeast and mold counts and formation of biogenic amines (BA) during 9 days of storage at +4 °C temperature were observed. VP and MAP effectively inhibited ACC, yeast and mold counts and level of BA in minced pork meat (P<0.05) during 9 days of storage at +4 °C temperature. LA and its mixtures with DHQ and TH statistically significantly reduced the ACC, E. coli count, total amount of BA and meat pH (in all cases P<0.05) in comparison with control samples in VP. In general, results suggest that adding a combination of all three additives resulted in a product with a distinctly longer shelf life in VP. These results could arise as an interesting approach for the improvement of food preservation using more natural procedures, considering the current demand of consumer and sensory quality of foods. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the phenotypic and genotypic antimicrobial resistance, integrons, and transferability of resistance markers in 243 aerobic bacteria recovered from pork at slaughter in the People's Republic of China. The organisms belonged to 22 genera of gram-negative bacteria (92.2%) and gram-positive bacteria (7.8%). High levels of resistance were detected to tetracycline, trimethoprim-sulfamethoxazole, and ampicillin (36.2 to 54.3%), and lower levels were detected to nitrofurantoin, cefotaxime, gentamicin, ciprofloxacin, and chloramphenicol (7.8 to 29.2%). Across species, genes conferring antimicrobial resistance were observed with the following frequencies: blaTEM, 40.7%; blaCMY-2, 15.2%; blaCTX-M, 11.5%; sul2, 27.2%; sul1, 14.4%; tet(A), 5.4%; tet(L), 5.4%; tet(M), 5.0%; tet(E), 3.7%; tet(C), 3.3%; tet(S), 2.5%; and tet(K), 0.8%. Various antimicrobial resistance genes were found in new carriers: blaTEM in Lactococcus garvieae, Myroides odoratimimus, Aeromonas hydrophila, Staphylococcus sciuri, Raoultella terrigena, Macrococcus caseolyticus, Acinetobacter ursingii, Sphingobacterium sp., and Oceanobacillus sp.; blaCMY-2 in Lactococcus lactis, Klebsiella oxytoca, Serratia marcescens, Acinetobacter baumannii, and Myroides phaeus; tet(L) in M. caseolyticus; sul1 in Vibrio cincinnatiensis; sul2 in Acinetobacter bereziniae, Acinetobacter johnsonii, and V. cincinnatiensis; and the class 1 integron and gene cassette aadA2 in V. cincinnatiensis. Approximately 6.6% of isolates contained class 1 integrons, and one isolate harbored class 2 integrons. Plasmid associated intI1 and androgen receptor-encoding genes were transferred into Escherichia coli J53 and E. coli DH5α by conjugation and transformation experiments, respectively. Our study highlights the importance of aerobic bacteria from pork as reservoirs for antimicrobial resistance genes and mobile genetic elements that can readily be transferred intra- and interspecies. [ABSTRACT FROM AUTHOR]

Aims To gain an understanding of the growth kinetics of Staphylococcus aureus to ensure the safety of pork, and to develop a predictive growth model of Staph. aureus in raw pork, ham and sausage pork under specific storage time and temperature conditions. Methods and Results Growth of Staph. aureus was evaluated at 5-40°C using 5-6 replicates in each sampling time in order to capture experimental variability. Growth curves were fit to Baranyi model to estimate Lag time ( λ) and maximum growth rate ( μmax). The effect of temperature on λ and μmax was modelled using natural logarithm of λ and square root of μmax. The variability between repetitions was higher at 15, 20 and 40°C than observed at 25, 30 and 35°C. After only 3 and 2 days of storage at 5 and 10°C, respectively, Staph. aureus populations decreased to limit of detection (≤1 log CFU g−1). Staphylococcus aureus populations on ham presented higher μmax in comparison to those grown on raw pork and sausage. Linear regression lines showed that Staph. aureus populations in ham grew faster than those observed in sausage and raw pork. Staph. aureus presented a theoretical minimum growth temperature ( Tmin) depending on the processed pork products, which were different from in raw pork. Conclusion Staphylococcus aureus model predicts faster growth in ham compared to raw pork and sausage. The validation of models showed good predictions, suggesting that the developed models are useful in estimating growth kinetics of Staph. aureus in different pork products. Significance and Impact of this Study Established here is a data-driven, in silico model on Staph. aureus growth kinetics on different pork products. The model is extensively validated by experiments and simulations and further supported by comparisons to previous modelling efforts in other species. [ABSTRACT FROM AUTHOR]