Microbiological, rheological and physical-chemical characteristics of bovine meat subjected to a prolonged ageing period

he aim of this study was to evaluate the effects of a long ageing period on the microbiological, rheological and physical-chemical characteristics of bovine beef. For the trial n. 3 Marchigiana bovine breed (live weight of 760 kg approximately), slaughtered at 34 months were chosen and the loin muscles were undergone to a prolonged ageing process. The analytical determinations performed were: pH and aw values, texture profile analysis, Warner-Bratzler shear force, colour (CIE L*a*b*), centesimal analysis, total bacterial count, Enterobacteriaceae, Listeria monocytogenes, yeasts and moulds. The results indicate that extended ageing has a negative effect on weight loss but, by the means of the standardization of dry aging parameters, reduce lipid oxidation and improve tendernes

The influence of broilers’ body weight on the efficiency of electrical stunning and meat quality under field conditions

Water-bath stunning represents the most-applied stunning system in poultry slaughtering, but within the European Union, specific indications on electric parameters that should be used, such as voltage, are missing. The objective of this study was to evaluate the efficiency of two commercially available types of electrical equipment (A and B) on broilers with different live body weights and the influence of the tested parameters on meat quality. Experimental trials in a European Union-approved slaughterhouse were carried out using two different stunners. 6600 broilers, divided into three weight groups, were stunned applying different protocols based on the same current frequencies and intensity but different voltages. The state of unconsciousness (presence of corneal reflex and wings flapping) and post-mortem defects (pectoral hemorrhages and dark meat) were evaluated by blinded trained operators. The presence of corneal reflex and petechiae were the most reported consciousness signs and post-mortem injuries, respectively. Different weights played an important role within stunner A, registering statistical differences (p < 0.01) among groups. Considering injuries, an inverse relationship between body weight and lesions was found. The results highlighted the effectiveness of both stunning systems applying the best combination of electrical parameters considering the weight of the animal and ensuring its well-being

Wild boars as reservoir for Campylobacter and Arcobacter

Campylobacteriosis is a significant public health concern with Campylobacter jejuni and Campylobacter coli as main causative agents. Moreover, there is an increasing recognition of other pathogenic Campylobacter species and Campylobacter-like organisms as Arcobacter. However, current knowledge on presence of Arcobacter species in wild boars (Sus scrofa) is lacking, and knowledge on Campylobacter species is based on methods favoring growth of thermotolerant species. In this study, fecal samples originating from 76 wild boars hunted in Campania region (Italy) were examined for the presence of Campylobacter(-like) organisms by a culture dependent approach. Three isolation protocols were performed in parallel: Arcobacter-selective agar plates, mCCDA plates and isolation by passive filtration onto non-selective blood agar plates were used as quantitative isolation methods. Enrichment broths, i.e. Arcobacter selective enrichment broth, Preston broth and CAT broth were used for qualitative detection of low levels or stressed Campylobacter(-like) organisms. The Arcobacter and Campylobacter isolates were identified at species level using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S ribosomal RNA (rRNA) sequence analysis. Overall, 41 (53.9%) of the animals excreted Arcobacter or Campylobacter while 38 (50.0%) shed Campylobacter and 8 (10.5%) Arcobacter. Campylobacter lanienae predominated and was isolated from 31 (40.8%) animals. No statistical difference between the age groups or gender with regard to the fecal excretion of Campylobacter(-like) organisms was observed. Thirty animals (39.5%) shed Campylobacter spp. exceeding levels of 10 ³ CFU g−1 feces. As samples were obtained from hunted wild boars intended for consumption, a potential contamination of meat with these bacterial pathogens must be considered

Comparison of droplet digital PCR vs real-time PCR for Yersinia enterocolitica detection in vegetables

: Yersiniosis - the 4th most commonly reported zoonosis in the European Union - is caused by the consumption of food contaminated with the bacterium Yersinia enterocolitica. The number of human cases and contaminated food samples is probably underestimated since conventional molecular methods currently proposed for Yersinia enterocolitica detection proved to have several limitations. Critical issues associated with the detection of Yersinia enterocolitica in meat and/or meat product has already been investigated, whereas data on the possible limits of the molecular methods for Yersinia enterocolitica detection in vegetables are still lacking. According to ISO method (ISO 18867:2015), real-time polymerase chain reaction (rtPCR) should be adopted for Yersinia enterocolitica detection, even if it proved to be affected by some biases. Recently, Droplet Digital PCR (ddPCR) has been introduced as a useful tool to detect and quantify different pathogenic bacteria in complex food matrices. However, its potential application for Yersinia enterocolitica detection in vegetables has never been investigated before. In the present study two molecular platforms (rtPCR and ddPCR) were used to evaluate the pathogen's behaviour in experimentally contaminated leafy greens (Lactuca sativa L.) and to assess the rate of detection achievable after the incubation for eleven days at different temperatures. By comparing, noticeable differences emerged between the two technical approaches: only ddPCR allowed the detection of the pathogen in leafy greens when contaminated at low levels. Moreover, results of the present work highlighted the importance of length and temperature of incubation on the survival and/or the growth of Yersinia enterocolitica in vegetables: at 18 and 25 °C the concentration of the pathogen considerably decreases along incubation. Based on data, the use of rtPCR leads to an underestimation of the true prevalence of pathogenic Y. enterocolitica in vegetables, while temperature and time currently proposed for Y. enterocolitica (25 °C for 24 h), allow optimizing detection. To conclude, ddPCR may be undoubtedly proposed as a reliable alternative strategy for the quick detection of the pathogen in food samples

Antimicrobial susceptibility testing for salmonella serovars isolated from food samples: Five-year monitoring (2015–2019)

The continuous collection and analysis of updated data on the antimicrobic resistance among bacterial strains represent the essential core for the surveillance of this problem. The present work aimed to investigate the occurrence of antimicrobial resistance among Salmonella serovars isolated in foods in 2015–2019. A total of 178 Salmonella strains belonging to 39 serovars were tested against 10 antimicrobials. High proportions of Salmonella isolates were resistant to tetracycline (n = 53.9%), ciprofloxacin (n = 47.2%), ampicillin (n = 44.4%), nalidixic acid (n = 42.7%), and trimethoprim-sulfamethoxazole (n = 38.8%). Different resistance rates were recorded among the different serotypes of Salmonella, and S. Infantis, exhibited the highest resistance to antibiotics. A high percentage of strains isolated from poultry, pork, and bovine were resistant to at least one or two antimicrobials. Resistant and multidrug-resistant (MDR) strains were also recorded among the isolates from molluscan shellfish; however, the occurrence of resistant Salmonella strains isolated from this source was significantly lower compared with those reported for poultry, pork, and bovine. The high levels of resistance reported in the present study indicate a potential public health risk. Consequently, additional hygiene and antibiotic stewardship practices should be considered for the food industry to prevent the prevalence of Salmonella in foods

Microbial Toxins in Dairy Products , chapter 9: Approaches to Assess the Risks/Modellingof Microbial Growth and Toxin Production

Chapter 9: Food-borne diseases, including those via dairy products, have been recognised as major threats to human health. The causes associated with dairy food-borne disease are the use of raw milk in the manufacture of dairy products, faulty processing conditions during the heat treatment of milk, post-processing contamination, failure in due diligence and an unhygienic water supply. Dairy food-borne diseases affecting human health are associated with certain strains of bacteria belonging to the genera of Clostridium, Bacillus, Escherichia, Staphylococcus and Listeria, which are capable of producing toxins, plus moulds that can produce mycotoxins such as aflatoxins, sterigmatocytin and ochratoxin. Microbial Toxins in Dairy Products reviews the latest scientific knowledge and developments for detecting and studying the presence of these toxins in dairy products, updating the analytical techniques required to examine bacterial and mould toxins and the potential for contamination of milk as it passes along the food chain, i.e. from 'farm-to-fork'. This comprehensive and accessible collection of techniques will help dairy processors, food scientists, technologists, researchers and students to further minimise the incidences of dairy food-borne illnesses in humans. The EU (2002) laid down the general principles and requirements of food law where it had changed the approach to food safety through the integrated control of the food chain, that is, the concept ‘from farm to table’, the precautionary principle, the responsibilities of food business operators, the traceability at all stage of food chain, and the introduction of ‘risk analysis’ (Codex Alimentarius Commission-FAO, 1999). The scope of a risk assessment is dependent on the risk management question and the reason for doing the assessment. The microbiological risk assessment would reveal, for example, either the sources of exposure to the pathogen or determine which pathogen(s) may be present in a specific and/or group of cheeses. This approach is largely a qualitative evaluation of the risk issue. in the process. If a hazard identification is orientated towards the food, then the focus will be on the use of available epidemiological and microbiological data to determine which pathogens could be associated with the products. In the dairy chain, contesting the hazard identification is linked to the microbiological quality of raw milk, the cheesemaking process including raw and/or pasteurization of the milk, maturation of the pressed curd, cross‐contamination, packaging, and handling at home

Determination of the microbiological contamination in minced pork by culture dependent and 16S amplicon sequencing analysis

Routine evaluation of bacterial contamination in minced pork is still mainly performed by the enumeration of indicator bacteria, including total aerobic colony count and E. coli, using standardized isolation methods. However, the bacterial community structure as well as the effect of the storage time and temperature on the aerobic plate count are largely unknown for this matrix. The aim of the study was to characterize the microbial community in minced pork by 16S rRNA amplicon sequencing compared to classical isolation methods combined with identification by Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI TOF MS) and 16S rRNA gene sequencing. Analysis of 14 unrelated samples showed that total aerobic counts determined at 30 °C and 7 °C showed no significant difference, but the richness was higher on PCA at 30 °C for 7 samples, equal in 5, and higher at 7 °C for 2 samples. Members of the genus Pseudomonas, along with the genera Brochothrix and Carnobacterium were commonly identified among both the mesophilic and psychrotrophic population. Comparing to 16S rRNA amplicon sequencing, some contrasting data were obtained. Except for Brochothrix spp. and Pseudomonas spp., that were abundant and always detected, genera obtained with the two methods in the same sample were not always the same. Comparison of different sample preparation techniques and DNA extraction methods demonstrated also in this matrix that different results on the microbial composition and complexity are obtained. Present data illustrate that the combined isolation and identification of isolates using MALDI TOF MS and 16S gene sequencing and overall community profiling using 16S rRNA amplicon sequencing provides complementary results and yields important insights into the complex relationship between microorganisms in a food

Yersinia enterocolitica detection in pork products: Evaluation of isolation protocols

Conventional methods for Yersinia enterocolitica detection in food samples are generally considered inadequate. Problems arise from the presence of the so-called “background flora”, coupled to the low contamination level of the pathogen. Since, data on the microbial ecology occurring in competitive microflora are still lacking, MALDI TOF MS was used for strains ‘identification after enrichment in PSB or ITC broths, and after plating on selective CIN medium at different incubation times. SYBR Green Real time PCR was used for the Y. enterocolitica strains’ detection (4/O:3, 1A/O:5) in experimentally contaminated foods, as well as in naturally contaminated samples. A higher number of different bacterial genera (10 on CIN and 18 on PCA) was recorded after enrichment in PSB, whilst enrichment in ITC led to recovery of 6 and 10 genera on CIN and PCA, respectively. Yersiniaceae was the dominant family on the first day of incubation, but on the second day the percentage of isolation considerably decreased. By testing experimentally contaminated samples, substantial difficulties were encountered. The biotype 1A was always detected, whereas strain 4/O:3 proved to be poorly competitive. Based on the data, the enrichment media PSB and ITC, currently proposed for Y. enterocolitica detection, need to be improved to promote a successful pathogen's recovery

Examining the Veterinary Electronic Antimicrobial Prescriptions for Dogs and Cats in the Campania Region, Italy: Corrective Strategies Are Imperative

: Companion animals are increasingly being recognised as important contributors to the spread of antimicrobial-resistant bacteria. The present work aimed to measure the antimicrobial drug prescribing in dogs and cats in the Campania Region, Italy by analysing the Veterinary Electronic Prescriptions (VEPs) between 2019 and 2020. The medical records associated with antimicrobial drug prescriptions were collected according to the drug administration (systemic or topical) and the rationale for the treatment chosen. In the period under investigation, 166,879 drugs were prescribed of which 129,116 (73.4%) were antimicrobial. A total of 83,965 (65%) antibiotics were prescribed to dogs, 40,477 (31.4%) to cats, and 4674 (3.6%) to other companion animals. In dogs, 90.5% of VEPs prescribed for systemic treatment included an antimicrobial Critically Important or Highly Important or Important for human medicine (WHO, 2018). The most widely prescribed class was fluoroquinolones. The antimicrobials prescribed were mainly metronidazole-spiramycin (29.7%), amoxicillin-clavulanic (19.6%), enrofloxacin and cephalexin in dogs (16.5%) and enrofloxacin (22.6%) and amoxicillin-clavulanic acid (21.4%) in cats. Based on the results, the widespread use of broad-spectrum antimicrobials and the use of molecules for which limitations should be observed according to the EMA guidelines has emerged