Characterization of Bacillus megaterium, Bacillus pumilus, and Paenibacillus polymyxa isolated from a Pinot noir wine from Western Washington State.
This report provides the first confirmed evidence of Bacillus-like bacteria present in a wine from Washington State. These bacteria were isolated from a 2013 Pinot noir wine whose aroma was sensorially described as being 'dirty' or 'pond scum.' Based on physiological traits and genetic sequencing, three bacterial isolates were identified as Bacillus megaterium (strain NHO-1), Bacillus pumilus (strain NHO-2), and Paenibacillus polymyxa (strain NHO-3). These bacteria grew in synthetic media of low pH (pH 3.5) while some survived ethanol concentrations up to 15% v/v. However, none tolerated molecular SO2 concentrations ≥0....
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: von Cosmos NH, Watson BA, Fellman JK, Mattinson DS, Edwards CG Tags: Food Microbiol Source Type: research

Enteric bacteria of food ice and their survival in alcoholic beverages and soft drinks.
This study aimed to evaluate the levels of enteric bacteria in ice cubes produced in different environments (home-made, prepared in bars and pubs with ice machines and produced in industrial plants) and to determine their survival in different alcoholic beverages and soft drinks. Members of the Enterobacteriaceae family were found in almost all samples analysed. All industrial and the majority of home-made samples did not contain coliforms. Enterococci were not identified in domestic samples while they were detected in two industrial and three bar/pub samples. The samples collected from bars and pubs were characterized by ...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Gaglio R, Francesca N, Di Gerlando R, Mahony J, De Martino S, Stucchi C, Moschetti G, Settanni L Tags: Food Microbiol Source Type: research

Milk-originated Bacillus cereus sensu lato strains harbouring Bacillus anthracis-like plasmids are genetically and phenotypically diverse.
Abstract Bacillus cereus sensu lato is widely distributed in food products, including raw and processed milk. Plasmids often determine bacterial virulence and toxicity, but their role in the evolution of B. cereus sensu lato is only partly known. Here, we observed that nearly 8% of B. cereus sensu lato isolates were positive for pXO1-like plasmids and 12% for pXO2-like plasmids in raw and ultra-heat-treated (UHT) milk from one dairy plant. However, pXO1-like plasmids were significantly more frequent in raw milk, while pXO2-like plasmids were more frequent in processed milk. Strains from raw and UHT milk ...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Bartoszewicz M, Marjańska PS Tags: Food Microbiol Source Type: research

Gene expression as a good indicator of aflatoxin contamination in dry-cured ham.
In this study, the influence of different water activity (aw) and temperatures on the temporal relative expression of three genes involved in AFs biosynthesis and their relationship with AFs production on dry-cured ham-based medium were evaluated. In general, the regulatory aflR and aflS genes showed similar expression patterns, and the expression of the structural aflP gene was much higher than that obtained for aflR and aflS genes. Regarding A. flavus, a decrease of aw regardless of temperature caused an increase of the expression of the regulatory aflR and aflS genes. Concerning A. parasiticus, the highest and...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Peromingo B, Rodríguez M, Delgado J, Andrade MJ, Rodríguez A Tags: Food Microbiol Source Type: research

Fusarium proliferatum - Causal agent of garlic bulb rot in Spain: Genetic variability and mycotoxin production.
ero D Abstract Fusarium proliferatum is a world-wide occurring fungal pathogen affecting several crops included garlic bulbs. In Spain, this is the most frequent pathogenic fungus associated with garlic rot during storage. Moreover, F. proliferatum is an important mycotoxigenic species, producing a broad range of toxins, which may pose a risk for food safety. The aim of this study is to assess the intraspecific variability of the garlic pathogen in Spain implied by analyses of translation elongation factor (tef-1α) and FUM1 gene sequences as well as the differences in growth rates. Phylogenetic characte...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Gálvez L, Urbaniak M, Waśkiewicz A, Stępień Ł, Palmero D Tags: Food Microbiol Source Type: research

Light based technologies for microbial inactivation of liquids, bead surfaces and powdered infant formula.
This study evaluates the potential of continuous wave Ultraviolet C light (UV-C) and broad-spectrum intense pulsed light (in this study referred to as High Intensity Light Pulses, HILP) for the inactivation of pathogens of public concern in powdered infant formula (PIF) producers. To achieve this goal a sequential set of experiments were performed, firstly in clear liquid media, secondly on the surface of spherical beads under agitation and, finally in PIF. L. innocua was the most sensitive microorganism to both technologies under all conditions studied with reductions exceeding 4 log10 cycles in PIF. In the clear liq...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Arroyo C, Dorozko A, Gaston E, O'Sullivan M, Whyte P, Lyng JG Tags: Food Microbiol Source Type: research

Tolerance development in Listeria monocytogenes-Escherichia coli dual-species biofilms after sublethal exposures to pronase-benzalkonium chloride combined treatments.
This study was designed to assess the effects that sublethal exposures to pronase (PRN) and benzalkonium chloride (BAC) combined treatments have on Listeria monocytogenes-Escherichia coli dual-species biofilms grown on stainless steel in terms of tolerance development (TD) to these compounds. Additionally, fluorescence microscopy was used to observe the changes of the biofilm structure. PRN-BAC exposure was carried out using three different approaches and TD was evaluated treating biofilms with a final 100 μg/ml PRN followed by 50 μg/ml BAC combined treatment. Results showed that exposure to PRN-BAC signifi...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Rodríguez-López P, Cabo ML Tags: Food Microbiol Source Type: research

Detection and prevalence of protozoan parasites in ready-to-eat packaged salads on sale in Italy.
Abstract To investigate the prevalence of protozoan contamination by Giardia duodenalis, Cryptosporidium spp., Toxoplasma gondii and Cyclospora cayetanensis, in 'ready to eat' (RTE) salads on sale in Italy, 648 packages were purchased from industrial and local brands. Nine individual packages from each brand were collected per month, pooled and subjected to microscopy and molecular analyses. Microscopic examination of 864 slides detected Cryptosporidium spp. but also Blastocystis hominis and Dientamoeba fragilis. Molecular tools identified G. duodenalis assemblage A, Cryptosporidium parvum and Cryptosporidium...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Caradonna T, Marangi M, Del Chierico F, Ferrari N, Reddel S, Bracaglia G, Normanno G, Putignani L, Giangaspero A Tags: Food Microbiol Source Type: research

Effect of storage temperature on the lag time of Geobacillus stearothermophilus individual spores.
Abstract The lag times (λ) of Geobacillus stearothermophilus single spores were studied at different storage temperatures ranging from 45 to 59 °C using the Bioscreen C method. A significant variability of λ was observed among individual spores at all temperatures tested. The storage temperature affected both the position and the spread of the λ distributions. The minimum mean value of λ (i.e. 10.87 h) was observed at 55 °C, while moving away from this temperature resulted in an increase for both the mean and standard deviation of λ. A Cardinal Model with I...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Kakagianni M, Aguirre JS, Lianou A, Koutsoumanis KP Tags: Food Microbiol Source Type: research

Modeling the risk of salmonellosis from consumption of pistachios produced and consumed in the United States.
Abstract The risk of salmonellosis from consumption of pistachios produced and consumed in the U.S. was assessed through quantitative microbial risk assessment. Data on Salmonella prevalence and concentration on pistachios, nut crop volume, storage times and temperatures during processing and handling, and reductions during storage or from roasting were derived from laboratory experiments, published literature, and industry expert opinion. Uncertainty was analyzed via what-if scenarios for Salmonella prevalence, concentration, storage reduction, treatment variability, portion of crop treated, and increased consump...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Lambertini E, Barouei J, Schaffner DW, Danyluk MD, Harris LJ Tags: Food Microbiol Source Type: research

Slightly acidic electrolyzed water combined with chemical and physical treatments to decontaminate bacteria on fresh fruits.
Abstract Effect of sequential combination of slightly acidic electrolyzed water (SAEW) with chemical and physical treatments on bacterial decontamination on fruits was investigated in this study. Effect of treatments on microbial and sensory quality was also analyzed after subsequent storage at 4 °C and room temperature (RT, 23 ± 0.15 °C). Whole apple and tomato fruits were inoculated with cocktail strains of Escherichia coli O157:H7 and Listeria monocytogenes. Uninoculated and inoculated fruits were washed first with distilled water (DW), calcium oxide (CaO), fumaric acid (FA), ...
Source: Food Microbiology - June 28, 2017 Category: Food Science Authors: Tango CN, Khan I, Ngnitcho Kounkeu PF, Momna R, Hussain MS, Oh DH Tags: Food Microbiol Source Type: research

Quantitative proteomics reveals new insights into calcium-mediated resistance mechanisms in Aspergillus flavus against the antifungal protein PgAFP in cheese.
Asensio MA Abstract The ability of Aspergillus flavus to produce aflatoxins in dairy products presents a potential hazard. The antifungal protein PgAFP from Penicillium chrysogenum inhibits various foodborne toxigenic fungi, including Aspergillus flavus. However, PgAFP did not inhibit A. flavus growth in cheese, which was related to the associated cation content. CaCl2 increased A. flavus permeability and prevented PgAFP-mediated inhibition in potato dextrose broth (PDB). PgAFP did not elicit any additional increase in permeability of CaCl2-incubated A. flavus. Furthermore, PgAFP did not alter meta...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Delgado J, Owens RA, Doyle S, Núñez F, Asensio MA Tags: Food Microbiol Source Type: research

Industrial-scale application of Lactobacillus reuteri coupled with glycerol as a biopreservation system for inhibiting Clostridium tyrobutyricum in semi-hard ewe milk cheese.
P, Garde S Abstract The suitability of the biopreservation system formed by reuterin-producing L. reuteri INIA P572 and glycerol (required for reuterin production) to prevent late blowing defect (LBD) was evaluated in industrial sized semi-hard ewe milk cheese contaminated with Clostridium tyrobutyricum INIA 68, a wild strain isolated from a LBD cheese. For this purpose, six batches of cheese were made (three with and three without clostridial spores): control cheeses with lactococci starter, cheeses with L. reuteri as adjunct, and cheeses with L. reuteri and 30 mM glycerol. Spores of C. ...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Ávila M, Gómez-Torres N, Delgado D, Gaya P, Garde S Tags: Food Microbiol Source Type: research

Longitudinal monitoring of Listeria monocytogenes and Listeria phages in seafood processing environments in Thailand.
Abstract Listeria monocytogenes is a foodborne pathogen commonly found in environments of seafood processing, thus presenting a challenge for eradication from seafood processing facilities. Monitoring the prevalence and subtype diversity of L. monocytogenes together with phages that are specific to Listeria spp. ("Listeria phages") will provide knowledge on the bacteria-phage ecology in food processing plants. In this work, a total of 595 samples were collected from raw material, finished seafood products and environmental samples from different sites of a seafood processing plant during 17 sampling...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Vongkamjan K, Benjakul S, Kim Vu HT, Vuddhakul V Tags: Food Microbiol Source Type: research

Survey on the phage resistance mechanisms displayed by a dairy Lactobacillus helveticus strain.
In this study the presence and functionality of phage defence mechanisms in Lactobacillus helveticus ATCC 10386, a strain of dairy origin which is sensitive to ΦLh56, were investigated. After exposure of ATCC 10386 to ΦLh56, the whole-genome sequences of ATCC 10386 and of a phage-resistant derivative (LhM3) were compared. LhM3 showed deletions in the S-layer protein and a higher expression of the genes involved in the restriction/modification (R/M) system. Genetic data were substantiated by measurements of bacteriophage adsorption rates, efficiency of plaquing, cell wall protein size and by gene expression analysis...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Zago M, Orrù L, Rossetti L, Lamontanara A, Fornasari ME, Bonvini B, Meucci A, Carminati D, Cattivelli L, Giraffa G Tags: Food Microbiol Source Type: research

Characterization of antimicrobial properties of Salmonella phage Felix O1 and Listeria phage A511 embedded in xanthan coatings on Poly(lactic acid) films.
Abstract Beyond simply providing a barrier between food and external contaminants, active packaging technologies aim to inhibit pathogen survival and growth within the packaged environment. Bacteriophages have a proven track record as targeted antimicrobials but have yet to be successfully integrated in active packaging without serious loss of activity. We have developed two bacteriophage based xanthan coatings on poly(lactic acid) (PLA) film which significantly inhibits Salmonella Typhimurium and Listeria monocytogenes growth in culture (P 
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Radford D, Guild B, Strange P, Ahmed R, Lim LT, Balamurugan S Tags: Food Microbiol Source Type: research

Multiple microbial cell-free extracts improve the microbiological, biochemical and sensory features of ewes' milk cheese.
This study used cell-free enzyme (CFE) extracts from Lactobacillus casei, Hafnia alvei, Debaryomyces hansenii and Saccharomyces cerevisiae to condition or accelerate Pecorino-type cheese ripening. Compositional, microbiological, and biochemical analyses were performed, and volatile and sensory profiles were obtained. Lactobacilli and cocci increased during ripening, especially in cheeses containing CFE from L. casei, H. alvei and D. hansenii (LHD-C) and L. casei, H. alvei and S. cerevisiae (LHS-C). Compared to control cheese (CC), several enzymatic activities were higher (P 
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Calasso M, Mancini L, De Angelis M, Conte A, Costa C, Del Nobile MA, Gobbetti M Tags: Food Microbiol Source Type: research

Effect of different marinating conditions on the evolution of spoilage microbiota and metabolomic profile of chicken breast fillets.
Abstract Five different marinades were prepared containing lemon juice, apple cider vinegar, pomegranate juice and combinations of them. Three different temperatures (4, 10, and 20 °C) and five marinating time intervals (1, 3, 6, and 9 h) were tested. Microbial, physicochemical as well as sensory analyses were performed to assess marination. Noticeable microbial reductions and satisfactory sensory results were observed only in samples treated for short time (1 and 3 h). The marinade in which pomegranate and lemon juices were combined caused a decrease in microbial counts and led to desirable sen...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Lytou AE, Panagou EZ, Nychas GE Tags: Food Microbiol Source Type: research

Effect of green tea extract on enteric viruses and its application as natural sanitizer.
ute;nchez G Abstract In this work, the effect of green tea extract (GTE) was assessed against murine norovirus (MNV) and hepatitis A virus (HAV) at different temperatures, exposure times and pH conditions. Initially, GTE at 0.5 and 5 mg/ml were individually mixed with each virus at 5 log TCID50/ml and incubated 2 h at 37 °C at different pHs (from 5.5 to 8.5). GTE affected both viruses depending on pH with higher reductions observed in alkaline conditions. Secondly, different concentrations of GTE (0.5 and 5 mg/ml) were mixed with viral suspensions and incubated for 2 or 16 h at 4,...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Randazzo W, Falcó I, Aznar R, Sánchez G Tags: Food Microbiol Source Type: research

Lack of viable parasites in cured 'Parma Ham' (PDO), following experimental Toxoplasma gondii infection of pigs.
Abstract Twelve Large White pigs were experimentally infected with 1000 Toxoplasma gondii oocysts/each. Serology was carried out at different time points post infection (p.i.) and animals were slaughtered at four months p.i. One of two thighs was examined for T. gondii infection status by PCR and bioassay in mice. The other thigh was processed for Parma ham production. Four thighs were examined after twelve months of curing, four after fourteen months and four were examined after sixteen months. Cured hams were analyzed by PCR, bioassay and in-vitro cultivation on Vero cells followed by real-time PCR. Pigs se...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Genchi M, Vismarra A, Mangia C, Faccini S, Vicari N, Rigamonti S, Prati P, Marino AM, Kramer L, Fabbi M Tags: Food Microbiol Source Type: research

Influence of soy fortification on microbial diversity during cassava fermentation and subsequent physicochemical characteristics of garri.
This study investigated the influence of the addition of soy products on the microbiology, nutritional and physico-chemical characteristics of garri, a fermented cassava product. Malted soy flour (MSF) and soy protein (SP) were separately added (12% w/w) to cassava mash prior to controlled fermentation, while non-supplemented cassava mash served as a control. Identification of lactic acid bacteria (LAB) and aerobic mesophilic bacteria was accomplished by repetitive sequence based (rep)-PCR analysis and 16S rRNA gene sequencing. Physicochemical, nutritional and sensory characterisation of control and soy-fortified garri was...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Ahaotu NN, Anyogu A, Obioha P, Aririatu L, Ibekwe VI, Oranusi S, Sutherland JP, Ouoba LII Tags: Food Microbiol Source Type: research

Large-scale targeted metagenomics analysis of bacterial ecological changes in 88 kimchi samples during fermentation.
Abstract The microbial communities in kimchi vary widely, but the precise effects of differences in region of origin, ingredients, and preparation method on the microbiota are unclear. We analyzed the bacterial community composition of household (n = 69) and commercial (n = 19) kimchi samples obtained from six Korean provinces between April and August 2015. Samples were analyzed by barcoded pyrosequencing targeting the V1-V3 region of the 16S ribosomal RNA gene. The initial pH of the kimchi samples was 5.00-6.39, and the salt concentration was 1.72-4.42%. Except for sampling locality, all categ...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Lee M, Song JH, Jung MY, Lee SH, Chang JY Tags: Food Microbiol Source Type: research

Factors influencing the Salmonella internalization into seedpods and whole plants of Arachis hypogaea (L.).
Abstract Here we investigated whether Salmonella enterica serovar Typhimurium ATCC 14028 was capable of internalizing in peanut seedpods and plants when exposed to inoculated soil and the edaphic factors that influenced uptake. Intact dry Virginia (DV) and fresh green Virginia (GV) seedpods were exposed to soil containing 6.5 Log (CFU/g) Salmonella under different soil moisture conditions. Internalization of S. Typhimurium into peanut plants germinated in inoculated soil was also examined with and without Bradyrhizobium (Arachis) sp.NC92. Salmonella counts recovered from GV seedpods were on average of 2.0 Log (CFU...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Rossbach JD, Fink RC, Sadowsky MJ, Tong C, Diez-Gonzalez F Tags: Food Microbiol Source Type: research

Efficacy of gaseous ozone to counteract postharvest table grape sour rot.
Abstract This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non-Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium a...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Pinto L, Caputo L, Quintieri L, de Candia S, Baruzzi F Tags: Food Microbiol Source Type: research

Effects of heat, cold, acid and bile salt adaptations on the stress tolerance and protein expression of kefir-isolated probiotic Lactobacillus kefiranofaciens M1.
Abstract Lactobacillus kefiranofaciens M1 is a probiotic strain isolated from Taiwanese kefir grains. The present study evaluated the effects of heat, cold, acid and bile salt adaptations on the stress tolerance of L. kefiranofaciens M1. The regulation of protein expression of L. kefiranofaciens M1 under these adaptation conditions was also investigated. The results showed that adaptation of L. kefiranofaciens M1 to heat, cold, acid and bile salts induced homologous tolerance and cross-protection against heterologous challenge. The extent of induced tolerance varied depending on the type and conditi...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Chen MJ, Tang HY, Chiang ML Tags: Food Microbiol Source Type: research

Leuconostoc strains isolated from dairy products: Response against food stress conditions.
rez V Abstract A systematic study about the intrinsic resistance of 29 strains (26 autochthonous and 3 commercial ones), belonging to Leuconostoc genus, against diverse stress factors (thermal, acidic, alkaline, osmotic and oxidative) commonly present at industrial or conservation processes were evaluated. Exhaustive result processing was made by applying one-way ANOVA, Student's test (t), multivariate analysis by Principal Component Analysis (PCA) and Matrix Hierarchical Cluster Analysis. In addition, heat adaptation on 4 strains carefully selected based on previous data analysis was assayed. The strains revealed...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: D'Angelo L, Cicotello J, Zago M, Guglielmotti D, Quiberoni A, Suárez V Tags: Food Microbiol Source Type: research

Comparison of Listeria monocytogenes recoveries from spiked mung bean sprouts by the enrichment methods of three regulatory agencies.
Abstract Three selective enrichment methods, the United States Food and Drug Administration's (FDA method), the United States Department of Agriculture Food Safety Inspection Service's (USDA method), and the EN ISO 11290-1 standard method, were assessed for their suitability for recovery of Listeria monocytogenes from spiked mung bean sprouts. Three parameters were evaluated; the enrichment L. monocytogenes population from singly-spiked sprouts, the enrichment L. monocytogenes population from doubly-spiked (L. monocytogenes and Listeria innocua) sprouts, and the population differential resulting from the enrichmen...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Cauchon KE, Hitchins AD, Smiley RD Tags: Food Microbiol Source Type: research

Controlling Brochothrix thermosphacta as a spoilage risk using in-package atmospheric cold plasma.
This study ascertained the potential of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) for control of B. thermosphacta, taking microbial and food environment factors into consideration, and investigated the shelf-life of lamb chop after in-package plasma treatment in modified atmosphere. Community profiling was used to assess the treatment effects on the lamb microflora. ACP treatment (80 kV) for 30s inactivated B. thermosphacta populations below detection levels in PBS, while 5 min treatment achieved a 2 Log cycle reduction using a complex meat model medium and attached cells. The antim...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Patange A, Boehm D, Bueno-Ferrer C, Cullen PJ, Bourke P Tags: Food Microbiol Source Type: research

High relative humidity pre-harvest reduces post-harvest proliferation of Salmonella in tomatoes.
Abstract Outbreaks of human illness caused by enteric pathogens such as Salmonella are increasingly linked to the consumption of fruits and vegetables. Knowledge on the factors affecting Salmonella proliferation on fresh produce therefore becomes increasingly important to safeguard public health. Previous experiments showed a limited impact of pre-harvest production practices on Salmonella proliferation on tomatoes, but suggested a significant effect of harvest time. We explored the data from two previously published and one unpublished experiment using regression trees, which allowed overcoming the interpretation...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Devleesschauwer B, Marvasi M, Giurcanu MC, Hochmuth GJ, Speybroeck N, Havelaar AH, Teplitski M Tags: Food Microbiol Source Type: research

Molecular investigation of bacterial communities during the manufacturing and ripening of semi-hard Iranian Liqvan cheese.
In this study, the microbiota of the milk, curd and cheese has been investigated using culture independent approaches. Denaturing gradient gel electrophoresis (DGGE) of the bacteria, 16S rRNA based high-throughput sequencing and enumeration of the live bacterial community by means of quantitative PCR (qPCR) have been used for this purpose. The results showed that the main bacterial population in the milk belonged to both microbial contaminants and lactic acid bacteria (LAB). However, both of these populations were totally replaced by LAB during ripening. The present survey contributes by describing the microbiota of this a...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Ramezani M, Hosseini SM, Ferrocino I, Amoozegar MA, Cocolin L Tags: Food Microbiol Source Type: research

Testing commercial biopreservative against spoilage microorganisms in MAP packed Ricotta fresca cheese.
Abstract Ricotta fresca cheese is susceptible to secondary contamination and is able to support the growth of pathogens or spoilage psychotrophic bacteria during storage. The aim of the present study was to evaluate which among three commercial biopreservatives was suitable to be used to control the growth of spoilage microorganisms in sheep's milk MAP ricotta fresca cheese. 144 Ricotta fresca cheese samples were inoculated either with the bioprotective culture Lyofast FPR 2 (including Enterococcus faecium, Lactobacillus plantarum e Lactobacillus rhamnosus) or Lyofast CNBAL (Carnobacterium spp) or the fermentate M...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Spanu C, Scarano C, Piras F, Spanu V, Pala C, Casti D, Lamon S, Cossu F, Ibba M, Nieddu G, De Santis EPL Tags: Food Microbiol Source Type: research

Impact of solar radiation exposure on phyllosphere bacterial community of red-pigmented baby leaf lettuce.
Abstract Solar radiation has been identified as a stress factor affecting phyllosphere associated bacteria colonization and survival during primary production. In the present study, the impact of different solar radiation doses on the phyllosphere microbiota of red-pigmented baby leaf lettuce cultivated in open field under commercial conditions was evaluated. Four weeks before harvest, the growing field was divided into four plots; each one was consecutively covered with one-week-interval with a light-excluding plastic to reduce the sunlight exposure. Four different solar radiation treatments were generated and cu...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Truchado P, Gil MI, Reboleiro P, Rodelas B, Allende A Tags: Food Microbiol Source Type: research

Microbiological, biochemical, and functional aspects of sugary kefir fermentation - A review.
Abstract Sugary kefir beverage is produce by fermenting raw sugar solution with kefir grains, the latter consisting of polysaccharide and microorganisms. This beverage, with great consumption in countries such as USA, Japan, France, and Brazil, represents a promising market to functional cultured drinks. This paper reviews the microbial diversity and interaction, kinetics, safety, and bioactivities of sugary kefir fermentation. The literature reviewed here demonstrates that sugary kefir possesses a similar microbial association relative to traditional milk kefir fermentation, especially among lactic acid bacteria ...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: Fiorda FA, de Melo Pereira GV, Thomaz-Soccol V, Rakshit SK, Pagnoncelli MGB, Vandenberghe LPS, Soccol CR Tags: Food Microbiol Source Type: research

Synergistic mixtures of chitosan and Mentha piperita L. essential oil to inhibit Colletotrichum species and anthracnose development in mango cultivar Tommy Atkins.
This study assessed the efficacy of chitosan (CHI) and Mentha piperita L. essential oil (MPEO) alone or in combination to control the mycelial growth of five different Colletotrichum species, C. asianum, C. dianesei, C. fructicola, C. tropicale and C. karstii, identified as potential anthracnose-causing agents in mango (Mangifera indica L.). The efficacy of coatings of CHI and MPEO mixtures in controlling the development of anthracnose in mango cultivar Tommy Atkins was evaluated. CHI (2.5, 5, 7.5 and 10 mg/mL) and MPEO (0.3, 0.6, 1.25, 2.5 and 5 μL/mL) alone effectively inhibited myce...
Source: Food Microbiology - June 5, 2017 Category: Food Science Authors: de Oliveira KÁR, Berger LRR, de Araújo SA, Câmara MPS, de Souza EL Tags: Food Microbiol Source Type: research

In-package inhibition of E.  coli O157:H7 on bulk Romaine lettuce using cold plasma.
In-package inhibition of E. coli O157:H7 on bulk Romaine lettuce using cold plasma. Food Microbiol. 2017 Aug;65:1-6 Authors: Min SC, Roh SH, Niemira BA, Boyd G, Sites JE, Uknalis J, Fan X Abstract Dielectric barrier discharge atmospheric cold plasma (DACP) treatment was evaluated for the inactivation of Escherichia coli O157:H7, surface morphology, color, carbon dioxide generation, and weight loss of bulk Romaine lettuce in a commercial plastic clamshell container. The lettuce samples were packed in a model bulk packaging configuration (three rows with either 1, 3, 5, or 7 layers) in the containe...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Min SC, Roh SH, Niemira BA, Boyd G, Sites JE, Uknalis J, Fan X Tags: Food Microbiol Source Type: research

Microbial quality of irrigation water used in leafy green production in Southern Brazil and its relationship with produce safety.
This study evaluated the distribution of generic E. coli and the prevalence of E. coli O157:H7 in two different water sources (ponds and streams bordering farmlands and urban areas) used for irrigation and on commercially produced lettuces in Southern Brazil. We also evaluated the effect of agricultural factors and meteorological conditions in the potential contamination of water and produce samples. A longitudinal study was conducted on four farms during a year (July 2014 to August 2015). The results showed generic E. coli prevalence of 84.8% and 38.3% in irrigation water samples and on lettuces, respective...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Decol LT, Casarin LS, Hessel CT, Batista AC, Allende A, Tondo EC Tags: Food Microbiol Source Type: research

Oregano essential oil-based natural antimicrobial packaging film to inactivate Salmonella enterica and yeasts/molds in the atmosphere surrounding cherry tomatoes.
This study investigated the effectiveness of a polyvinyl alcohol (PVA) film containing the natural antimicrobial oregano essential oil (OEO) as an active packaging application for decreasing the microbial growth. The film exerted an antimicrobial effect via the atmosphere surrounding the food rather than direct contact, thereby preserving the quality of cherry tomatoes. A packaging film containing microencapsulated OEO was developed. The loading content increased gradually (104.29-234.29 μg OEO/mg film) with the amount of OEO incorporated (1%, 2%, and 3%), where the PVA films containing 2% OEO had the highest loadi...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Kwon SJ, Chang Y, Han J Tags: Food Microbiol Source Type: research

Prevalence and molecular characterization of Staphylococcus aureus in commercially available meat over a one-year period in Iowa, USA.
Abstract Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of infectious disease morbidity and mortality. Previous studies have confirmed the presence of S. aureus, including MRSA, on raw meat products. We investigated the prevalence and molecular epidemiology of S. aureus and MRSA in commercially-distributed antibiotic-free and conventional raw meat products (n = 3290) purchased in 8 Iowa retail stores weekly for a period of one year. Isolates were characterized using spa typing, and PCR was used to detect the presence of the Panton-Valentine leukocidin (PVL) and mecA genes...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Thapaliya D, Forshey BM, Kadariya J, Quick MK, Farina S, O' Brien A, Nair R, Nworie A, Hanson B, Kates A, Wardyn S, Smith TC Tags: Food Microbiol Source Type: research

Cereulide production by Bacillus weihenstephanensis strains during growth at different pH values and temperatures.
guyen-The C Abstract Besides Bacillus cereus, some strains of the psychrotolerant, potentially foodborne pathogen Bacillus weihenstephanensis can produce the emetic toxine (cereulide). This toxin is a heat- and acid-stable cyclic dodecadepsipeptide that causes food intoxication with vomiting. However, some severe clinical cases with lethal outcomes have been described. If cereulide can be produced during refrigerated storage, it will not be inactivated by reheating food, representing an important risk of food intoxication for consumers. In this paper, we determined the capacity of the B. weihenstephanensis st...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Guérin A, Rønning HT, Dargaignaratz C, Clavel T, Broussolle V, Mahillon J, Granum PE, Nguyen-The C Tags: Food Microbiol Source Type: research

Microbiota and metabolome during controlled and spontaneous fermentation of Nocellara Etnea table olives.
This study is aimed to investigate bacterial community and its dynamics during the fermentation of Nocellara Etnea table olives and to study its effect on metabolome formation. Six different combination of bacterial cultures (BC1-BC6) were used as starters for table olive fermentation and one additional process, conducted without addition of any starters, was used as control (C). The processes were conducted in triplicate and, overall, 21 vessels were performed at industrial scale. The fermentation was monitored for 120 days through culture-dependent and -independent approaches. Microbial counts of the main microbial group...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Randazzo CL, Todaro A, Pino A, Pitino I, Corona O, Caggia C Tags: Food Microbiol Source Type: research

Evaluation of qPCR and plate counting for quantifying thermophilic starters in cheese.
Abstract The respective inputs of plate counting and qPCR for the quantification of starters in cheese were evaluated using hard-cooked cheeses made with various starter combinations. Five starter strains were quantified at their different growth phases, from 0.5 h to day 214 of manufacture: one strain of Streptococcus thermophilus (ST) and two strains each of Lactobacillus delbrueckii (LD) and Lactobacillus helveticus (LH). Numbers of colony-forming units (CFU) were obtained by plate counting (PC) and qPCR (GNCFU). The qPCR standard curves require a special attention since GNCFU depends on the degree of cult...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Achilleos C, Berthier F Tags: Food Microbiol Source Type: research

Bacterial ecology of artisanal Minas cheeses assessed by culture-dependent and -independent methods.
This study aimed to characterize the microbial diversity composition, and geographical distribution of artisanal Minas cheese, focusing on the characterization of its autochthonous lactic acid bacteria (LAB) microbiota. Artisanal Minas cheese varieties from Serro, Canastra, Serra do Salitre, Araxá and Campo das Vertentes were analyzed by culture-dependent (culturing and LAB sequencing) and -independent (repetitive extragenic palindromic-PCR (rep-PCR) and length heterogeneity-PCR, LH-PCR) methods to characterize the microbiota. The microbial counts were variable between cheese samples, and some samples presented high...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Perin LM, Savo Sardaro ML, Nero LA, Neviani E, Gatti M Tags: Food Microbiol Source Type: research

Effects of glucose and oxygen on arginine metabolism by coagulase-negative staphylococci.
In this study, the conversion of the amino acid arginine by two strains with arginine deiminase (ADI) activity (Staphylococcus carnosus 833 and S. pasteuri αs3-13) and a strain with nitric oxide synthase (NOS) activity (S. haemolyticus G110) was modelled as a function of glucose and oxygen availability. Both factors moderately inhibited the ADI-based conversion kinetics, never leading to full repression. However, for NOS-driven conversion of arginine by S. haemolyticus G110, oxygen was an absolute requirement. When changing from microaerobic conditions to aerobiosis, a switch from homolactic fermentati...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Sánchez Mainar M, Matheuse F, De Vuyst L, Leroy F Tags: Food Microbiol Source Type: research

Influence of growth conditions on adhesion of yeast Candida spp. and Pichia spp. to stainless steel surfaces.
Abstract An understanding of adhesion behavior of Candida and Pichia yeast under different environmental conditions is key to the development of effective preventive measures against biofilm-associated infection. Hence in this study we investigated the impact of growth medium and temperature on Candida and Pichia adherence using stainless steel (AISI 304) discs with different degrees of surface roughness (Ra = 25.20-961.9 nm), material typical for the food processing industry as well as medical devices. The adhesion of the yeast strains to stainless steel surfaces grown in Malt Extract broth (MEB) o...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Tomičić R, Raspor P Tags: Food Microbiol Source Type: research

Campylobacter jejuni survival in a poultry processing plant environment.
ssi M, Rovira J Abstract Campylobacteriosis is the most common cause of bacterial gastroenteritis worldwide. Consumption of poultry, especially chicken's meat is considered the most common route for human infection. The aim of this study was to determine if Campylobacter spp. might persist in the poultry plant environment before and after cleaning and disinfection procedures and the distribution and their genetic relatedness. During one month from a poultry plant were analyzed a total of 494 samples -defeathering machine, evisceration machine, floor, sink, conveyor belt, shackles and broiler meat- in order to isol...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: García-Sánchez L, Melero B, Jaime I, Hänninen ML, Rossi M, Rovira J Tags: Food Microbiol Source Type: research

Salmonella Weltevreden in integrated and non-integrated tilapia aquaculture systems in Guangdong, China.
This study aimed to determine differences in occurrence and characteristics of Salmonella spp. isolated from tilapia-pig and non-integrated aquaculture systems in Guangdong province, China. A total of 77 samples (9 pig feed, 19 fish feed, 9 pig faeces, 20 fish mucus and 20 fish intestine) from 10 tilapia-pig ponds and 10 non-integrated ponds were analysed. Salmonella spp. was found in fish mucus (20.0%), fish intestine (40.0%) and pig faeces (11.1%) from integrated ponds, and from fish mucus (40.0%) and fish intestine (40.0%) from non-integrated ponds. S. Weltevreden (76.5%) was by far the most common serovar showing limit...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Li K, Petersen G, Barco L, Hvidtfeldt K, Liu L, Dalsgaard A Tags: Food Microbiol Source Type: research

Exploring polyamine metabolism of Alternaria alternata to target new substances to control the fungal infection.
os AJ Abstract Polyamines are essential for all living organisms as they are involved in several vital cell functions. The biosynthetic pathway of polyamines and its regulation is well established and, in this sense, the ornithine descarboxylase (ODC) enzyme acts as one of the controlling factors of the entire pathway. In this work we assessed the inhibition of the ODC with D, l-α-difluoromethylornithine (DFMO) on Alternaria alternata and we observed that fungal growth and mycotoxin production were reduced. This inhibition was not completely restored by the addition of exogenous putrescine. Actually, increas...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Estiarte N, Crespo-Sempere A, Marín S, Sanchis V, Ramos AJ Tags: Food Microbiol Source Type: research

Effect of food-related stress conditions and loss of agr and sigB on seb promoter activity in S.  aureus.
Effect of food-related stress conditions and loss of agr and sigB on seb promoter activity in S. aureus. Food Microbiol. 2017 Aug;65:205-212 Authors: Sihto HM, Stephan R, Engl C, Chen J, Johler S Abstract Staphylococcal enterotoxin B (SEB) causes staphylococcal food poisoning and is produced in up to ten times higher quantities than other major enterotoxins. While Staphylococcus aureus growth is often repressed by competing flora, the organism exhibits a decisive growth advantage under some stress conditions. So far, data on the influence of food-related stressors and regulatory mutations on seb ...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Sihto HM, Stephan R, Engl C, Chen J, Johler S Tags: Food Microbiol Source Type: research

Toxoplasma gondii in raw and dry-cured ham: The influence of the curing process.
rera A, Bayarri S Abstract The aim of this work was to analyze Toxoplasma gondii in raw hams by mouse bioassay and to evaluate the effect of curing on the viability of the parasite to assess the risk of infection from eating dry-cured ham. After a serology study of 1200 pigs in Aragón (Spain), forty-one naturally infected pigs with different serological titers against T. gondii were selected. Two cured periods (9 and 12 months) were evaluated as well as the influence of the physicochemical composition of hams on T. gondii survival. Although the parasite burden was low, a high number of seropositiv...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Herrero L, Gracia MJ, Pérez-Arquillué C, Lázaro R, Herrera A, Bayarri S Tags: Food Microbiol Source Type: research

Microbiological quality of selected ready-to-eat leaf vegetables, sprouts and non-pasteurized fresh fruit-vegetable juices including the presence of Cronobacter spp.
This study was aimed at determining the microbiological quality of ready-to-eat (RTE) plant-origin food products available on the Polish market with special emphasis on the prevalence of Cronobacter genus bacteria. Analyses were carried out on 60 samples of commercial RTE type plant-origin food products, including: leaf vegetables (20 samples), sprouts (20 samples) and non-pasteurized vegetable, fruit and fruit-vegetable juices (20 samples). All samples were determined for the total count of aerobic mesophilic bacteria (TAMB) and for the presence of Cronobacter spp. The isolates of Cronobacter spp. were subjected to geneti...
Source: Food Microbiology - April 14, 2017 Category: Food Science Authors: Berthold-Pluta A, Garbowska M, Stefańska I, Pluta A Tags: Food Microbiol Source Type: research