Raw Dairy Products Research Articles

Comparative analysis of the effectiveness of analytical methods for the determination of aflatoxins in milk and dairy products (review information)

The dairy industry of Ukraine is developing dynamically, its needs for the quality of raw materials are growing significantly. Detection of mycotoxins in raw milk is one of the main indicators of its safety. The high degree of toxicity of mycotoxins is a threat to the health of the lactating animal, so a large number of them are excreted in milk. If we talk about ruminants, the vast majority of mycotoxins are utilized by microorganisms of the pancreas, which does not occur in monogastric animals, so the list of mycotoxins in their milk can be much wider than the secretion of mammalian mammals. To date, the maximum permissible levels (MRLs) of mycotoxins in raw milk and dairy products have been established. Thus, a comprehensive determination of the content of mycotoxins in the secretion of the breast has not only technological but also important diagnostic value. Milk sample preparation is the most important step in the determination of mycotoxins and consists of sampling, extraction and purification from impurities. For the extraction of aflatoxins, the method of liquid extraction with acetonitrile or chloroform is used. Purification of extracts is carried out on immunoaffinity columns, cartridges with special sorbents or using certain manufacturers (MycoSep®).Enzyme-linked immunosorbent assay and high-performance liquid chromatography with fluorescence detection are used to determine aflatoxin B1 and M1 in raw milk of cows. However, all these methods have a number of disadvantages, namely: long and expensive sample preparation and insufficiently high selectivity. Currently, the complex determination of mycotoxins in various matrices by high-performance liquid chromatography with mass spectrometric detection (LC-MS/MS) and the use of modified QuEChERS sample preparation is gaining popularity. The advantage of this technique is the combination of faster and cheaper sample preparation of QuEChERS samples with highly selective LC-MS/MS chromatography. Key words: mycotoxins, raw milk, analytical methods, QuEChERS.

Antibacterial Bioactivity of Some Lactic Acid Bacteria Isolated from Various Egyptian Products

The current research aimed to isolate and screening of antibacterial bioactive lactic acid bacteria (LAB) from different foods such as raw milk, dairy products and fermented meat and evaluate their potential for production of antibacterial substances, namely bacteriocins. Ten samples were collected from different market foods, examined and used for LAB isolation on MRS medium. A total of 71 bacterial isolates were selected based on some variation properties, such as color, shape, size and oxygen requirements. These isolates were confirmed as lactic acid bacteria based on their microscopic observation and chemical properties, i.e. catalase negative and acid producing from glucose fermentation. All selected isolates were grown on MRS medium at 37oC for 48 h, and compared to identified LAB strains, i.e. Lactococcus lactis, Streptococcus thermophilus, Befidobacterium sp, Lactobacillus casi, Lb rhamnosus, Lb. acidophilus, Lb. helveticus and Lb. plantarum. Isolates and strains were surveyed for bacteriocin production as inhibitory activity test. Partial purification of bacteriocin was carried out by salt precipitation method; this method was done by ammonium sulphate 40-60% saturation and centrifuged at 9500 rpm for 20 minutes at 4oC. Some of microbial indicator strains found to test by inhibitory biological activity substance (partial purification of bacteriocin) produced by lactic acid cultures. Indicator strains such as staphylococcus aureus, Listeria monocytogenes and others were grown by nutrient agar at 37o C for 24h. An inhibitory activity test was executed by paper diffusion method. The inhibition effect was examined by form clear inhibition zone around indicator strains. Twenty-eight isolates and the 8 LAB strains showed bioactivities against the tested pathogens. Gram positive indicator bacteria were found to be the most sensitive to inhibitory substances produced by LAB culture as compared to gram negative indicator strains. Staphylococcus aureus was exhibited the highest sensitivity to it. The highest bacteriocins activities were produced by strain Lactobacillus rhamnosus while R5 and S6 from LAB isolates. They were shown broad spectrum against gram positive and gram-negative pathogenic bacteria. Diameters of inhibition zone refer to degree of sensitive between indicator strains and bacteriocin activity

Aflatoxins in Milk and Dairy Products: Occurrence and Exposure Assessment for the Serbian Population

The main objective of this study was to assess the exposure associated with aflatoxin M1 (AFM1) of the adult population in Serbia from consumption of milk and dairy products. This assessment was performed using concentration values of AFM1 in raw milk (385 samples) and dairy products (556 samples) based on the analyses conducted in the period between 2015 and 2018. In parallel, a dairy products consumption survey was completed during 2018 based on ‘one-day’ and ‘seven-day’ recall methods. In order to estimate the intake of AFM1 from the consumption of dairy products for both recall methods, a Monte Carlo simulation was conducted. The study revealed that pasteurized milk and yogurt are dairy products mostly consumed by the Serbian adult population. Estimated daily intake of AFM1 was in the range of 62–74 × 10−3 ng/kg bw/day, depending on the recall methods and scenarios employed. Although the results show moderate exposure risks compared to similar studies worldwide, climatic conditions and weather extremes that have occurred recently may have negatively influenced the contamination of feed and, consequently, AFM1 contamination of milk. As a result, it is justifiable to promote continuous monitoring in feed and dairy supply chains in Serbia and provide an update of exposure assessment.

Identification and Monitoring of Lactobacillus delbrueckii Subspecies Using Pangenomic-Based Novel Genetic Markers.

Genetic markers currently used for the discrimination of Lactobacillus delbrueckii subspecies have low efficiency for identification at subspecies level. Therefore, our objective in this study was to select novel genetic markers for accurate identification and discrimination of six L. delbrueckii subspecies based on pangenome analysis. We evaluated L. delbrueckii genomes to avoid making incorrect conclusions in the process of selecting genetic markers due to mislabeled genomes. Genome analysis showed that two genomes of L. delbrueckii subspecies deposited at NCBI were misidentified. Based on these results, subspecies-specific genetic markers were selected by comparing the core and pangenomes. Genetic markers were confirmed to be specific for 59,196,562 genome sequences via in silico analysis. They were found in all strains of the same subspecies, but not in other subspecies or bacterial strains. These genetic markers also could be used to accurately identify genomes at the subspecies level for genomes known at the species level. A real-time PCR method for detecting three main subspecies (L. delbrueckii subsp. delbrueckii, lactis, and bulgaricus) was developed to cost-effectively identify them using genetic markers. Results showed 100% specificity for each subspecies. These genetic markers could differentiate each subspecies from 44 other lactic acid bacteria. This real-time PCR method was then applied to monitor 26 probiotics and dairy products. It was also used to identify 64 unknown strains isolated from raw milk samples and dairy products. Results confirmed that unknown isolates and subspecies contained in the product could be accurately identified using this real-time PCR method.

Prevalence of Staphylococcus aureus, Klebsiella spp., Escherichia coli and Pseudomonas spp. in some common Bangladeshi milk and dairy products

The study was done to isolate Klebsiella spp., Staphylococcus aureus, Escherichia coli & Pseudomonas spp. from raw milk, processed milk (powdered milk & ultra-high-temperature milk) and dairy products (mango milk, and ice cream). During 3 months’ time span of study, a total of ten samples were gathered where eight of the samples powdered milk (2), ultra-high-temperature milk (2), ice cream (2) & mango milk (2) were gathered from different places of Bangladesh & other 2 samples (raw milk) were collected from a cattle farm & individual households in & around Noakhali city. The samples were gathered under aseptic safety measures and were followed by plating on non-selective media (Nutrient broth) & selective media (Mannitol Salt Agar & Macconkey agar). The presumptive Klebsiella spp., Staphylococcus aureus, Escherichia coli & Pseudomonas spp. isolates were identified by biochemical tests. Analysis of the result discovered that out of a total of 10 samples; raw milk (2), processed milk i.e. powdered milk (2), ultra-high-temperature milk (2) and dairy products i.e. mango milk (2) and ice cream (2) resulted in the isolation of 8 isolates (2.5%) of S. aureus, (12.5%) of Klebsiella spp., (2.5%) of Pseudomonas spp. & (2.5%) of Escherichia coli. Results recommended a probability of potential public health threat of Staphylococcus aureus, Klebsiella spp., Escherichia coli & Pseudomonas spp. resulting from contamination of milk and dairy products with pathogenic microorganisms is mainly due to unhygienic practices and conditions in the handling, production, and processing.

Molecular epidemiology of methicillin-resistant Staphylococcus aureus from dairy farms in North-eastern Italy

Transmission of Staphylococcus aureus along the dairy production chain is an emerging public health problem with human, veterinary, and food safety issues. The prevalence of multidrug-resistant, particularly methicillin-resistant S. aureus (MRSA), has steadily increased in several European countries. In this study, the prevalence of S. aureus in raw cow milk and farm workers was investigated, and the trajectories of MRSA transmission at the primary stage of the dairy chain were assessed. To this purpose, a longitudinal survey was conducted in 618 dairy farms in two contiguous regions with high livestock density in North-eastern Italy. S. aureus contamination of bulk tank milk (BTM) was observed in more than 80% of farms, while MRSA prevalence was 3.6% and 15.9% in BTM and farm workers, respectively. The majority of MRSA isolates from both BTM and farm workers were assigned to ST398, and showed a worrisome multidrug-resistant phenotype. Enterotoxin and Panton-Valentine leukocidin genes were detected in 11.5% and 4.9% of MRSA isolates from both sources. Nearly all MRSA isolates from workers belonged to the same epidemiological type as BTM isolates from the corresponding farm, denoting a bidirectional MRSA transmission pattern. A focus on the ST398 spa type t899 MRSA lineage in the Italian livestock system highlighted the presence of two major clusters whose dissemination was likely facilitated by the selective pressure imposed by antimicrobial use in animal farming. Our findings emphasize the need for continuous monitoring of MRSA along the dairy production chain, not only to avoid transmission between animals and exposed workers, but also to contain the risk of raw milk and dairy product contamination by multidrug resistant and toxigenic strain.

Potential of N2 Gas Flushing to Hinder Dairy-Associated Biofilm Formation and Extension.

Worldwide, the dairy sector remains of vital importance for food production despite severe environmental constraints. The production and handling conditions of milk, a rich medium, promote inevitably the entrance of microbial contaminants, with notable impact on the quality and safety of raw milk and dairy products. Moreover, the persistence of high concentrations of microorganisms (especially bacteria and bacterial spores) in biofilms (BFs) present on dairy equipment or environments constitutes an additional major source of milk contamination from pre- to post-processing stages: in dairies, BFs represent a major concern regarding the risks of disease outbreaks and are often associated with significant economic losses. One consumption trend toward “raw or low-processed foods” combined with current trends in food production systems, which tend to have more automation and longer processing runs with simultaneously more stringent microbiological requirements, necessitate the implementation of new and obligatory sustainable strategies to respond to new challenges regarding food safety. Here, in light of studies, performed mainly with raw milk, that considered dominant “planktonic” conditions, we reexamine the changes triggered by cold storage alone or combined with nitrogen gas (N2) flushing on bacterial populations and discuss how the observed benefits of the treatment could also contribute to limiting BF formation in dairies.

Safety Assessment and Preliminary In Vitro Evaluation of Probiotic Potential of Lactococcus lactis Strains Naturally Present in Raw and Fermented Milk.

The present study was conducted to find the potential of Lactococcus lactis strains naturally present in raw and fermented milk as probiotics and to evaluate their safety and some technological characteristics. There are numerous studies that evaluated probiotic properties of lactococci, nevertheless, limited studies on the probiotic potential of lactococci isolated from raw milk or dairy products were performed. Strains isolation from raw milk or dairy products and their characterization is important when selection of starter strains for the production of functional dairy foods is performed. Depending on aroma production and acidifying activity, 33 L. lactis strains were selected out of 169 and evaluated for safety, technological and probiotic properties. These strains were screened for antibiotic sensitivity, enzymatic activity, hemolytic and gelatinase activities. The strains were also assessed for resistance to bile salts and acid, growth in bile acids and cholesterol, cell surface hydrophobicity. Based on the obtained results, two strains with the best probiotic potential were selected. These two L. lactis strains, with 51% and 67% survival at low pH and more than 80% resistance to various bile salt concentrations, proved their resistance in vitro to gastric conditions. Also these strains proved to be good acidifiers (the pH of milk was reduced by at least 1 unit in 6h at 30-37°C) and can be used in the development of functional dairy foods as starter cultures.

Tick-borne encephalitis outbreak following raw goat milk consumption in a new micro-location, Croatia, June 2019

In June 2019, the Croatian Institute of Public Health was informed of a cluster of patients with laboratory confirmed tick-borne encephalitis (TBE) from the Gorski Kotar region. Five of the six patients with TBE reported consuming raw (unpasteurized) goat milk in the two week period before symptom onset, and one reported a recent tick bite. To assess risk factors for infection, we selected six control individuals from among healthy family and community members, and conducted a case-control analysis. None of the cases or controls were vaccinated against TBE. Individuals with TBE (cases) had 25 (95 % CI 0.8-1410.2, p = 0.021) times higher odds of raw goat milk consumption compared to healthy controls. Milk samples from 12 goats from the implicated farm were tested for the TBE virus (TBEV) using RT-PCR. TBEV RNA was not detected in the milk, but serological testing of goats and other farm animals yielded evidence of exposure to the virus: Six goats from the flock had TBEV neutralizing antibodies. Our findings suggest that the vehicle for the outbreak was raw goat milk from a single farm. Following public health advice to cease consumption of raw dairy products, no further cases have been reported.

Screening of Salmonella enterica Serovars, Typhi, Typhimurium, and Enteritidis in Raw Milk and Dairy Products in South-Khorasan, Iran: Conventional versus Molecular Method

Background and Objective: Food-borne Salmonellosis has been reported as the second most common bacterial infection. Salmonella enterica subsp. enterica serotype enteritidis (S. Enteritidis) and S. enterica subsp. enterica serotype typhimurium (S. Typhimurium) are the most common serotypes worldwide as salmonellosis agents. Salmonella yyphi is the causative agent of typhoid fever worldwide. The purpose of the present study was to determine the contamination rate of raw milk and dairy products to Salmonella typhi, S. typhimurium and S. Enteritidis in South-Khorasan, Iran. It is very important in food safety risk assessment and human health. Methods: A total of 260 raw milk and 181 dairy products were obtained from South-Khorasan, Iran. Dairy samples were pre-enriched in buffered peptone water and enriched in Rappaport Vassiliadis (RV). Raw milk was enriched in RV. Plating of the enriched samples was carried out on Xylose Lysine Desoxycholate (XLD) agar and Brilliant Green agar (BGA). All of the enriched samples were also tested by M-PCR for detection of S. typhi, S. typhimurium and S. Enteritidis. Results: Among the 441 tested samples only 4 samples were contaminated with Salmonella spp. in culture method. PCR assay, didn’t find any positive sample regarding Salmonella spp. In chi-square test, the difference of two methods of isolation was significant (P< 0.05). Conclusions: In conclusion, the results of the present study showed a good hygienic state of raw milk and dairy products. Enrichment based PCR assay is more economical than time-consuming culture method for Salmonella detection.

New Analytical Tools for Unmasking Frauds in Raw Milk-Based Dairy Products: Assessment, Validation and Application to Fiore Sardo PDO Cheese of a RP-HPLC Method for the Evaluation of the α-l-Fucosidase Activity

The activity of α-l-fucosidase (FSC) has been measured for the first time in Fiore Sardo PDO (Protected Designation of Origin) raw milk cheese. To do this, a RP-HPLC method has been developed, validated and tested on a reliable sampling of cheese experimentally produced in laboratory batches. Three experimental factors have been considered in this work: the thermal treatment undergone by the milk, the lactation period and the ripening time of cheese. Results obtained have evidenced: (i) a meaningful reduction in the activity of FSC from cheeses produced using raw milk to those obtained by thermized milk; (ii) an increase in the activity of FSC during the first months of lactation period (from December to February), followed by a substantial constancy in the central and final months of lactation (from February to May); (iii) the enzyme activity is independent of the ripening time. This method might be useful in revealing frauds related to the use of mild thermal treatments of the milk when this is not allowed as for Fiore Sardo PDO cheese but also for several PDO cheeses for which the specifications establish that raw milk only must be used for their production.

Investigation of BRUCELLA SPP in milk and dairy products and lifespan of BRUCELLA MELITENSIS and BRUCELLA ABORTUS in kefir

Brucellosis is common disease in our country and it is an important zoonotic infection that is up to date in terms of public health, animal industry and economic losses. The aim of this study was to determine Brucella IgG positivity of raw milk and dairy products purchased non-packed and non-labelled. In this study, a total of 450 samples including 250 raw milk, 100 white cheese, 50 butter and 50 yoghurt samples were investigated by ELISA method for Brucella IgG positivity. 85 (56.6 %) of 150 raw milk samples obtained from Sivas province center and surrounding villages, 32 (32 %) of 100 raw milk samples obtained from the milk deliverers of Tokat province center and Reşadiye and Pazar districts of Tokat were detected positive for Brucella spp. 2 (4 %) of 50 white cheese samples collected in Sivas province center and 9 (18 %) of 50 white cheese samples collected in Tokat province center were positive for Brucella spp. None of the yoghurt and butter samples were positive for Brucella IgG antibodiesAdditionally, in this study, the survival time of Brucella melitensis and Brucella abortus bacteria prepared in different bacterial density in kefir obtained from 3 different sources (A, B brand and homemade) were investigated. Bacteria in A and B brand kefir lived between 0-72 hours, while homemade kefir lived between 0-24 hours. No reproduction was observed at the end of the period. This study investigated Brucella Ig G positivity in milk and dairy products in Sivas and Tokat provinces and milk and dairy products may pose a risk for Brucellosis. Additionally, it was observed that Brucella could survive up to 3 days in probiotic fermented milk drink Kefir and the kefir suppresses Brucella growth.

Determination of bacteriocin-encoding genes of lactic acid bacteria isolated from traditional dairy products of Luxor province, Egypt

BackgroundResearchers have focused on isolating and identifying the bacteriocin producing lactic acid bacteria from various food systems especially dairy products. Molecular techniques have been recently used for rabid identification of bacteriocins rather than time-consuming biochemical characters. Global climate disturbances can affect the diversity of beneficial microorganisms in dairy and their products, especially lactic acid bacteria, so it is worth to evaluate their bacteriocinogenicity in different climates. Thus, the aim of this study was to screen for predominant bacteriocin producing lactic acid bacteria (LAB) in traditional dairy products of Luxor governorate at Upper Egypt and determine their bacteriocin-encoding genes.ResultsEighty-six strains of the LAB were isolated from raw milk and traditional dairy product of Luxor province, Egypt, in which 76.1% and 23.9% were identified as lactic acid bacilli and cocci, respectively. On the basis of their antibacterial potentials, 30 out of 68 LAB isolates were found to be antimicrobial producers. These isolates exhibited a potential antibacterial activity against Salmonella paratyphi B, Escherichia coli, Staphylococcus aureus, and Proteus mirabilis, except for Listeria monocytogenes. LAB isolates were analyzed using species-specific PCR; results emphasized that 22 of isolates were identified as Lactobacillus plantarum, while 8 were Leuconostoc mesenteroides. According to the sequencing of isolates, two strains named Lactobacillus plantarum Egypt 2018 (accession no. MH817034) and Leuconostoc mesenteroides Egypt 2018 (accession no. MH817035) were identified. Detection of bacteriocin-encoding genes was performed by polymerase chain reaction (PCR). The results emphasized that almost all tested Lb. plantarum strains (n = 10) possess both plnA and plnEF genes, whereas the gene encoding mesentericin Y105 was detected in one Lc. mesenteroides of the examined isolates.ConclusionsThis study was effective for the rapid detection of bacteriocin producing strains within dairy products. Extracted bacteriocin could be a valuable source of natural food biopreservative.

Prevalence of Human Brucellosis in a Suspected Population of District Swat

Background: Brucellosis is caused by a gram-negative, aerobic, non-spore forming, coccobacillus, transmitted by consumption ofcontaminated dairy products. Close contact with infected animals is also a risk factor. Diagnosis is difficult due to non-specificmanifestations like fever, back pain, arthralgia, muscle aches, and anemia, thereby diagnosis is based on laboratory tests.Although under rated, 50,000 new cases of human brucellosis worldwide are reported annually. In Pakistan, despite the diseasebeing endemic, data is limited. Moreover, the increased consumption of raw dairy products has posed an additional risk.Objective: To identify the prevalence of human brucellosis in the suspected population of District Swat.Material and Methods: This cross-sectional study was conducted at a tertiary-care hospital, of Swat from November 2017-October 2018. From the outpatient department, 150 participants were enrolled being suspected of having human brucellosis.Every participant was screened for Brucella antibodies by Serum Plate Agglutination Test (SPAT) and confirmed through Enzyme-Linked Immunosorbent Assay (ELISA) and Polymerase Chain Reaction (PCR).Results: The mean age of the participants was 29.65+11.27 years, 34% of which were 21-30 years of age. Most (62%, n=93) werefemales and a greater proportion of them consume fresh milk (45.3%), followed by fresh milk and milk pack both (30%). Around 119(79.3%) were positive on SPAT, 50.7% on ELISA, and 49.3% on PCR with a significantly higher proportion in females (p=0.001).Conclusion: Human brucellosis was found to be highly prevalent among suspected population exposed to raw dairy products witha definitive diagnosis found in almost half of the samples collected.

Zoonotic risks of pathogens from sheep and their milk borne transmission.

Sheep were domesticated around 9000 BC in the Middle East, and since then milk from sheep gradually became very popular, not only for drinking but also for making cheeses and other dairy products. Nowadays, these dairy products are also important for people with an allergy to cow milk, and these products are an essential part of the local daily diet in regions of the world that are not suitable for cows and goats. Consumption of raw milk and raw milk products has a zoonotic risk, and with regard to sheep, the main pathogens associated with such dairy products are: Brucella melitensis, Campylobacter spp., Listeria spp., Salmonella spp., Shiga-toxin producing Escherichia coli, Staphylococcus aureus, tick borne encephalitis virus, and Toxoplasma gondii. Especially, young children, elderly people, pregnant women and immunocompromised (YOPI) persons, and those suffering from disease should be aware of the risk of consuming raw milk and raw milk products. This latter risk can be reduced by proper flock health management, prevention of contamination during milking, adequate milk processing, transport, and refrigerated storage. Only processes equaling pasteurization sufficiently reduce zoonotic risks from milk and milk products, but proper cooling is essential and recontamination must be prevented. Therefore, strict hygiene practices throughout the production process and supply chain especially for raw milk and raw dairy products, should be applied. Small scale production systems pose a greater risk compared to industrialized production systems because of a less protocolized and controlled production process. This manuscript describes zoonotic risks of pathogens from sheep and their milk borne transmission. Additionally, routes of contamination, possibilities for multiplication, and prevention measures thereof are described. We summarize some major human outbreaks caused by consumption of sheep milk and products made thereof, and finally discuss their implications.

Taking Control: Campylobacter jejuni Binding to Fibronectin Sets the Stage for Cellular Adherence and Invasion.

Campylobacter jejuni, a foodborne pathogen, is one of the most common bacterial causes of gastroenteritis in the world. Undercooked poultry, raw (unpasteurized) dairy products, untreated water, and contaminated produce are the most common sources associated with infection. C. jejuni establishes a niche in the gut by adhering to and invading epithelial cells, which results in diarrhea with blood and mucus in the stool. The process of colonization is mediated, in part, by surface-exposed molecules (adhesins) that bind directly to host cell ligands or the extracellular matrix (ECM) surrounding cells. In this review, we introduce the known and putative adhesins of the foodborne pathogen C. jejuni. We then focus our discussion on two C. jejuni Microbial Surface Components Recognizing Adhesive Matrix Molecule(s) (MSCRAMMs), termed CadF and FlpA, which have been demonstrated to contribute to C. jejuni colonization and pathogenesis. In vitro studies have determined that these two surface-exposed proteins bind to the ECM glycoprotein fibronectin (FN). In vivo studies have shown that cadF and flpA mutants exhibit impaired colonization of chickens compared to the wild-type strain. Additional studies have revealed that CadF and FlpA stimulate epithelial cell signaling pathways necessary for cell invasion. Interestingly, CadF and FlpA have distinct FN-binding domains, suggesting that the functions of these proteins are non-redundant. In summary, the binding of FN by C. jejuni CadF and FlpA adhesins has been demonstrated to contribute to adherence, invasion, and cell signaling.

Brevilactibacter flavus gen. nov., sp. nov., a novel bacterium of the family Propionibacteriaceae isolated from raw milk and dairy products and reclassification of Propioniciclava sinopodophylli as Brevilactibacter sinopodophylli comb. nov.

Eight facultatively anaerobic rod-shaped bacteria were isolated from raw milk and two other dairy products. Results of phylogenetic analyses based on 16S rRNA gene sequences showed that the isolates are placed in a distinct lineage within the family Propionibacteriaceae with Propioniciclava sinopodophylli and Propioniciclava tarda as the closest relatives (94.6 and 93.5 % similarity, respectively). The cell-wall peptidoglycan contained meso-diaminopimelic acid, alanine and glutamic acid and was of the A1γ type (meso-DAP-direct). The major cellular fatty acid was anteiso-C15 : 0 and the major polar lipids were diphosphatidylglycerol, phosphatidyglycerol and three unidentified glycolipids. The quinone system contained predominantly menaquinone MK-9(H4). The G+C content of the genomic DNA of strain VG341T was 67.7 mol%. The whole-cell sugar pattern contained ribose, rhamnose, arabinose and galactose. On the basis of phenotypic and genetic data, eight strains (VG341T, WS4684, WS4769, WS 4882, WS4883, WS4901, WS4902 and WS4904) are proposed to be classified as members of a novel species in a new genus of the family Propionibacteriaceae, for which the name Brevilactibacter flavus gen. nov., sp. nov. is proposed. The type strain is VG341T (=WS4900T=DSM 100885T=LMG 29089T) and seven additional strains are WS4684, WS4769, WS4882, WS4883, WS4901, WS4902 and WS4904. Furthermore, we propose the reclassification of P. sinopodophylli as Brevilactibacter sinopodophylli comb. nov.

Detection of antibiotic resistance profiles and aminoglycoside-modifying enzyme (AME) genes in high-level aminoglycoside-resistant (HLAR) enterococci isolated from raw milk and traditional cheeses in Turkey.

The aim of this study was isolation and identification of the high-level aminoglycoside-resistant (HLAR) enterococci in raw milk and dairy products and to analyze their antibiotic resistance and the presence of aminoglycoside-modifying enzyme (AME) genes. A total of 59 HLAR enterococci were isolated from raw milk and traditional cheese samples. Thirty-nine of the 59 HLAR enterococci were isolated on streptomycin-containing agar medium, while the other 20 HLAR strains were isolated on gentamicin containing agar medium. The 59 HLAR enterococci were identified as 26 E. faecalis (44.07%), 18 E. faecium (30.51%), 13 E. durans (22.03%), and two E. gallinarum (3.39%) by species-specific PCR. Disk diffusion tests showed that teicoplanin were the most effective antibiotics used in this study, while 89.83% of isolates were found to be resistant to tetracycline. High rates of multiple antibiotic resistance were detected in HLAR isolates. Minimum inhibitory concentration (MIC) values of HLAR enterococci against streptomycin and gentamicin were found in the range of 64 to > 4096 µg/mL. Forty-seven (79.66%) of the 59 HLAR enterococci were found to be both high-level streptomycin-resistant (HLSR) and high-level gentamicin-resistant (HLGR) by MIC tests. However, no correlation was found between the results of the disk diffusion and MIC tests for gentamicin and streptomycin in some HLAR strains. The aph(3')-IIIa (94.92%) was found to be most prevalent AME gene followed by ant(4')-Ia (45.76%), ant(6')-Ia (20.34%) and aph(2'')-Ic (10.17%). None of the isolates contained the aac(6')-Ie-aph(2'')-Ia, aph(2'')-Ib or aph(2'')-Id genes. None of the AME-encoding genes were identified in E. durans RG20.1, E. faecalis RG22.4, or RG26.1. In conclusion, HLAR enterococci strains isolated in this study may act as reservoirs in the dissemination of antibiotic resistance genes.

CalcPEFDairy: A Product Environmental Footprint compliant tool for a tailored assessment of raw milk and dairy products

A compliant tool (CalcPEFDairy) to determine the Product Environmental Footprint (PEF) of Dairy products has been developed following the Product Environmental Footprint Category Rules (PEFCR) v.6.3 guidance and the 2018 approved PEFCR for Dairy products. CalcPEFDairy is a new tool that simplifies and reduces the work for LCA practitioners when implementing the PEFCR for Dairy products. On contrary to traditional LCA software, CalcPEFDairy includes all the emission models needed to calculate farm and crop cultivation direct emissions and it also implements the specific calculation formulas stated in the PEFCR such as the Circular Footprint and Data Quality Requirement formulas. Moreover, the PEF compliant datasets provided by the Life Cycle Data Network are incorporated in the tool as source of secondary data. To demonstrate the accuracy of the tool a traditional dairy farm in Catalonia (Northwest of Spain) was assessed and the results compared with the European representative PEF compliant datasets for the production of raw milk, cheese and yoghurt. In addition to the environmental profile, CalcPEFDairy has determined the case study's environmental single score (ESS) for the production of raw milk (1.0 × 10−4) cheese (9.7 × 10−6) and yoghurt (1.4 × 10−5); these ESS results are within the range of the ESS obtained from the analysed EF-datasets. The data sets' average ESS for raw milk is 9.9 × 10−5 ± 1.1 × 10−5, while for cheese and yoghurt are 1.5 × 10−5 ± 3.1 × 10−6 and 1.9 × 10−5 ± 3.4 × 10−6 respectively. A 78% of the raw milk production ESS is attributed to the dairy farm activities while, the raw milk production stage affects in a 87.4% and 80.1% to the ESS for cheese and yoghurt respectively.

Microbiological quality of raw drinking milk and unpasteurised dairy products: results from England 2013-2019.

The aim of this study was to review microbiology results from testing >2500 raw drinking milk and dairy products made with unpasteurised milk examined in England between 2013 and 2019. Samples were collected as part of incidents of contamination, investigation of infections or as part of routine monitoring and were tested using standard methods for a range of both pathogens and hygiene indicators. Results from testing samples of raw cow's milk or cheese made from unpasteurised milk for routine monitoring purposes were overall of better microbiological quality than those collected during incident or investigations of infections. Results from routine monitoring were satisfactory for 62% of milks, 82% of cream, 100% of ice-cream, 51% of butter, 63% of kefir and 79% of cheeses, with 5% of all samples being considered potentially hazardous. Analysis of data from cheese demonstrated a significant association between increasing levels of indicator Escherichia coli with elevated levels of coagulase positive staphylococci and decreased probability of isolation of Shiga toxin-producing E. coli. These data highlight the public health risk associated with these products and provide further justification for controls applied to raw drinking milk and dairy products made with unpasteurised milk.