Antimicrobial treatments to control Listeria monocytogenes in queso fresco.
lez F Abstract Queso fresco, is a Hispanic non-fermented cheese highly susceptible to contamination with L. monocytogenes. This research was aimed to determine the effect of GRAS antimicrobial ingredients to control L. monocytogenes. Antimicrobials included caprylic acid (CA), Nisaplin(®) (N, 2.5% nisin), a mixture of sodium lactate and sodium diacetate (SL/SD), Lactococcus lactis sbp. lactis DPC 3147, monolaurin, and lactic acid (LA). Batches of queso fresco curds were inoculated with 10(4) CFU/g and stored at 4 °C for three weeks. During storage the count of L. monocytogenes reac...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Lourenço A, Kamnetz MB, Gadotti C, Diez-Gonzalez F Tags: Food Microbiol Source Type: research

Influence of electro-activated solutions of weak organic acid salts on microbial quality and overall appearance of blueberries during storage.
r M Abstract The aim of this work was to study the potential of diluted electro-activated solutions of weak organic acid salts (potassium acetate, potassium citrate and calcium lactate) to extend the shelf life of blueberries during post-harvest storage. The sanitizing capacity of these solutions was studied against pathogenic bacteria Listeria monocytogenes and E. coli O157:H7 as well as phytopathogenic fungi A. alternata, F. oxysporum and B. cinerea. The results showed that a 5-min treatment of inoculated blueberries with electro-activated solutions resulted in a 4 log CFU/g reduction in List...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Liato V, Hammami R, Aïder M Tags: Food Microbiol Source Type: research

Meat sources of infection for outbreaks of human trichinellosis.
Abstract Trichinellosis is one of the most important foodborne zoonotic diseases, with worldwide distribution. While human risk for trichinellosis has historically been linked to pork, modern pork production systems and slaughter inspection programs have reduced or eliminated pork as a source for trichinellosis in many countries. While pork may no longer pose a significant risk for trichinellosis, many other animal species may be hosts for Trichinella species nematodes and when human consume meat from these animal species, there may be risk for acquiring trichinellosis. This review article describes the various no...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Rostami A, Gamble HR, Dupouy-Camet J, Khazan H, Bruschi F Tags: Food Microbiol Source Type: research

Incidence of osmophilic yeasts and Zygosaccharomyces rouxii during the production of concentrate grape juices.
, Combina M Abstract Zygosaccharomyces rouxii is the main spoilage yeast of grape juice concentrates. Detection and identification of Z. rouxii during the production of grape juice concentrate is critical to prevent spoilage in the final product. In this work, three grape juice concentrate processing plants were assessed by identifying osmophilic yeasts in juices and surfaces during different stages of a complete production line. Subsequently, molecular typing of Z. rouxii isolates was done to determine the strain distribution of this spoilage yeast. Osmotolerant yeast species, other than Z. rouxii,...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Rojo MC, Torres Palazzolo C, Cuello R, González M, Guevara F, Ponsone ML, Mercado LA, Martínez C, Combina M Tags: Food Microbiol Source Type: research

Hydrolysate from a mixture of legume flours with antifungal activity as an ingredient for prolonging the shelf-life of wheat bread.
Abstract Aiming at identifying antifungal compounds from plant matrices to be used as ingredients in the bakery industry, a water/salt-soluble extract (WSE) was produced from a legume enzyme hydrolysate, consisting of a mixture of pea, lentil, and faba bean flours, and assayed towards Penicillium roqueforti DPPMAF1. Agar diffusion assays allowed the selection of the optimal processing conditions for hydrolysis. As shown by hyphal radial growth rate, the inhibition was observed towards several fungi, including Aspergillus parasiticus CBS971.97, Penicillium carneum CBS 112297, Penicillium paneum CBS 101032, Penicill...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Rizzello CG, Verni M, Bordignon S, Gramaglia V, Gobbetti M Tags: Food Microbiol Source Type: research

Control of human pathogenic Yersinia enterocolitica in minced meat: Comparative analysis of different interventions using a risk assessment approach.
This study aimed to evaluate the effect of different processing scenarios along the farm-to-fork chain on the contamination of minced pork with human pathogenic Y. enterocolitica. A modular process risk model (MPRM) was used to perform the assessment of the concentrations of pathogenic Y. enterocolitica in minced meat produced in industrial meat processing plants. The model described the production of minced pork starting from the contamination of pig carcasses with pathogenic Y. enterocolitica just before chilling. The endpoints of the assessment were (i) the proportion of 0.5 kg minced meat packages t...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Van Damme I, De Zutter L, Jacxsens L, Nauta MJ Tags: Food Microbiol Source Type: research

The locus of heat resistance (LHR) mediates heat resistance in Salmonella enterica, Escherichia coli and Enterobacter cloacae.
This study aimed to determine the frequency of the LHR in food isolates of E. coli, and its influence on heat resistance in S. enterica and Enterobacter spp. Cell counts of LHR-positive strains of E. coli, S. enterica and E. cloacae were reduced by less than 1, 1, and 4 log (cfu/mL), respectively, after exposure to 60 °C for 5 min, while cell counts of LHR-negative strains of the same species were reduced by more than 7 log (cfu/mL). Introducing an exogenous copy of the LHR into heat-sensitive enteropathogenic E. coli and S. enterica increased heat resistance to a level that...
Source: Food Microbiology - February 20, 2017 Category: Food Science Authors: Mercer RG, Walker BD, Yang X, McMullen LM, Gänzle MG Tags: Food Microbiol Source Type: research

Nonthermal inactivation of norovirus surrogates on blueberries using atmospheric cold plasma.
This study investigated CP technology for the nonthermal inactivation of human norovirus surrogates, Tulane virus (TV) and murine norovirus (MNV), on the surface of blueberries. Blueberries (5 g) were weighed into sterile 4 oz. glass jars and inoculated with TV, 5 log PFU/g. Samples were treated with atmospheric CP for 0, 15, 30, 45, and 60 s at a working distance of 7.5 cm with 4 cubic feet/minute (cfm) of CP jet. Temperature readings were taken with an infrared camera prior to, and immediately following, CP treatments. In order to establish the impact of air flow during CP treatment (4 cfm), an additional ...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Lacombe A, Niemira BA, Gurtler JB, Sites J, Boyd G, Kingsley DH, Li X, Chen H Tags: Food Microbiol Source Type: research

Potential of a new strain of Bacillus amyloliquefaciens BUZ-14 as a biocontrol agent of postharvest fruit diseases.
Abstract The biocontrol potential of the Bacillus amyloliquefaciens strain BUZ-14 was tested against the main postharvest diseases of orange, apple, grape and stone fruit. After characterizing the temperature and pH growth curves of strain BUZ-14, its in vitro antifungal activity was determined against Botrytis cinerea, Monilinia fructicola, M. laxa, Penicillium digitatum, P. expansum and P. italicum. Subsequently, in vivo activity was tested against these pathogens by treating fruit with cells, endospores and cell-free supernatants. The in vitro results showed that BUZ-14 inhibited the gr...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Calvo H, Marco P, Blanco D, Oria R, Venturini ME Tags: Food Microbiol Source Type: research

Monitoring the mycobiota during Greco di Tufo and Aglianico wine fermentation by 18S rRNA gene sequencing.
In this study, we monitored fungal populations involved in spontaneous fermentations of Aglianico and Greco di Tufo grape must by high-throughput sequencing (HTS) of 18S rRNA gene amplicons. We firstly proposed an alternative/addition to ITS as target gene in HTS studies and highlighted consistency between the culture-dependent and -independent approaches. A complex mycobiota was found at the beginning of the fermentation, mainly characterized by non-Saccharomyces yeasts and several moulds, with differences between the two types of grapes. Moreover, Interdelta patterns revealed a succession of several Saccharomyces cerevis...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: De Filippis F, La Storia A, Blaiotta G Tags: Food Microbiol Source Type: research

Inactivation and changes in metabolic profile of selected foodborne bacteria by 460  nm LED illumination.
The objective of this study was to investigate the effect of 460 nm light-emitting diode (LED) on the inactivation of foodborne bacteria. Additionally, the change in the endogenous metabolic profile of LED illuminated cells was analyzed to understand the bacterial response to the LED illumination. Six different species of bacteria (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, Pseudomonas aeruginosa and Salmonella Typhimurium) were illuminated with 460 nm LED to a maximum dose of 4080 J/cm(2) at 4, 10 and 25 °C. Inactivation curves were modeled using Hom m...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Kumar A, Ghate V, Kim MJ, Zhou W, Khoo GH, Yuk HG Tags: Food Microbiol Source Type: research

Relative effectiveness of selected preenrichment media for the detection of Salmonella from leafy green produce and herbs.
Abstract Four buffered preenrichment media (BAX(®) System MP Media (BAX)), Universal Preenrichment Broth (UPB), modified Buffered Peptone Water (mBPW), and Buffered Peptone Water (BPW)) were compared with lactose broth (LB) in the Bacteriological Analytical Manual's (BAM) Salmonella culture method for the analysis of 9 leafy green produce and herb types. Artificially contaminated test portions were pre-enriched in each medium and the results were analyzed statistically using Fisher's Exact 2-tailed F test (p  0.05). UPB was consistently among the most effective media for recovery of Salmonella from t...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Jacobson AP, Wang H, Gill VS, Duvall R, Arce G, Chirtel S, Hammack TS Tags: Food Microbiol Source Type: research

Isolation, molecular and phenotypic characterization, and antibiotic susceptibility of Cronobacter spp. from Brazilian retail foods.
This study revealed the presence of Cronobacter spp. in foods commercialized in Brazil and the isolates showed a high diversity after MLST analysis and included two strains of the C. sakazakii ST4 neonatal meningitic pathovar. PMID: 28040160 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Brandão ML, Umeda NS, Jackson E, Forsythe SJ, de Filippis I Tags: Food Microbiol Source Type: research

Evaluation of the spoilage potential of bacteria isolated from chilled chicken in  vitro and in situ.
In this study, a total of 53 isolates, belonging to 7 species of 3 genera, were isolated using a selective medium based on the capacity to spoil chicken juice. Four isolates, namely Aeromonas salmonicida 35, Pseudomonas fluorescens H5, Pseudomonas fragi H8 and Serratia liquefaciens 17, were further characterized to assess their proteolytic activities in vitro using meat protein extracts and to evaluate their spoilage potential in situ. The in vitro studies showed that A. salmonicida 35 displayed the strongest proteolytic activity against both sarcoplasmic and myofibrillar proteins. However, the major spoilag...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Wang GY, Wang HH, Han YW, Xing T, Ye KP, Xu XL, Zhou GH Tags: Food Microbiol Source Type: research

Occurrence and characterization of food-borne pathogens isolated from fruit, vegetables and sprouts retailed in the Czech Republic.
A, Koláčková I, Karpíšková R Abstract Food of non-animal origin is a major component of the human diet and has been considered to pose a low risk from the point of view of bacteriological safety. However, an increase in the number of outbreaks of illness caused by such pathogens and linked to the consumption of fresh fruit and vegetables have been reported from around the world recently. Salmonella spp., STEC (Shiga toxin producing Escherichia coli) and Listeria monocytogenes are among the most frequently identified agents. Additionally, the transmission of antibiotic resistant...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Vojkovská H, Myšková P, Gelbíčová T, Skočková A, Koláčková I, Karpíšková R Tags: Food Microbiol Source Type: research

Differential gene expression and filamentation of Listeria monocytogenes 08-5923 exposed to sodium lactate and sodium diacetate.
This study reports the gene expression and filamentation in Listeria monocytogenes 08-5923 following exposure to food preservatives sodium lactate (NaL) and sodium diacetate (SD). L. monocytogenes 08-5923 was challenged with a mixture of NaL/SD, NaL or sodium acetate at 37 °C in tryptic soy broth. In the initial study, L. monocytogenes 08-5923 was exposed to NaL/SD for 24 h. The transcriptome was investigated by RNA sequencing. A stress response network was discovered in L. monocytogenes 08-5923, which is mediated by genes encoding two-component systems (hisJ, lisK, OmpR family gene, resE) and ...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Liu X, Basu U, Miller P, McMullen LM Tags: Food Microbiol Source Type: research

Bacteriocin-like substances of Lactobacillus curvatus P99: characterization and application in biodegradable films for control of Listeria monocytogenes in cheese.
a WP Abstract The aim of this study was to evaluate the effectiveness of a biodegradable film, with antimicrobial metabolites produced by Lactobacillus curvatus P99 incorporated, targeting the control of Listeria monocytogenes in sliced "Prato" cheese. Tests were performed to evaluate the spectrum of action of cell-free supernatant (CFS) of P99 against different microorganisms, as well as to detect the minimum inhibitory (MIC) and bactericidal (MBC) concentrations against L. monocytogenes Scott A. The detection of genes that encode for the production of bacteriocins and evaluation of their expressio...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Marques JL, Funck GD, Dannenberg GD, Cruxen CE, Halal SL, Dias AR, Fiorentini ÂM, Silva WP Tags: Food Microbiol Source Type: research

Antimicrobial susceptibility and genetic characterization of Escherichia coli recovered from frozen game meat.
The objective of this study was to evaluate the current antimicrobial susceptibility status in generic Escherichia coli isolated from packed frozen game meat from a game handling establishment in Germany. A total of 229 E. coli isolates were obtained from cuts of red deer, roe deer and wild boar. The susceptibility to 12 antimicrobial agents was evaluated by a broth microdilution method according to ISO 20776-1:2006. Minimal Inhibitory Concentration (MIC) values were compared to breakpoints and cut-off values published by the EUCAST. Isolates showing MICs above the reference values were further studied for associated ...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Mateus-Vargas RH, Atanassova V, Reich F, Klein G Tags: Food Microbiol Source Type: research

Dynamics of bacterial communities during manufacture and ripening of traditional Caciocavallo of Castelfranco cheese in relation to cows' feeding.
Abstract Traditional Caciocavallo of Castelfranco is a semi-hard "pasta-filata" cheese produced from raw cows' milk in Campania region. The aim of the present research is mainly focused on the study, by 16S rRNA gene pyrosequencing and viable counts, of the dynamics of bacterial communities during manufacture and ripening of traditional Caciocavallo cheese. Moreover, the possible correlation between cheese microbiota and cows' feeding based on silage or hay was also evaluated. In general, except for enterococci, the technological process significantly affected all the microbial groups. According to 16S r...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Giello M, La Storia A, Masucci F, Di Francia A, Ercolini D, Villani F Tags: Food Microbiol Source Type: research

Genetic diversity, safety and technological characterization of lactic acid bacteria isolated from artisanal Pico cheese.
Abstract A total of 114 lactic acid bacteria were isolated at one and 21 days of ripening from a traditional raw cow's milk cheese without the addition of starter culture, produced by three artisanal cheese-makers in Azores Island (Pico, Portugal). Identification to species and strain level was accomplished by16S rRNA gene and PFGE analysis. Carbohydrate utilization profiles were obtained with the relevant API kits. Isolates were evaluated according to safety and technological criteria. The most frequently observed genus identified by 16S rRNA sequencing analysis was Enterococcus, whereas API system mostly identif...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Domingos-Lopes MF, Stanton C, Ross PR, Dapkevicius ML, Silva CC Tags: Food Microbiol Source Type: research

Performance evaluation of volatile organic compounds by antagonistic yeasts immobilized on hydrogel spheres against gray, green and blue postharvest decays.
Abstract Wickerhamomyces anomalus, Metschnikowia pulcherrima, Aureobasidium pullulans and Saccharomyces cerevisiae yeasts were tested for their ability to survive and synthesize antifungal volatile organic compounds (VOCs) both in vitro and in vivo conditions when immobilized on commercial hydrogel spheres. The results showed a good survival of all yeasts on hydrogel spheres up to 10 days of incubation. Moreover, VOCs produced in vitro by tested yeasts inhibited Botrytis cinerea, Penicillium digitatum and P. italicum radial growth and conidial germination, with the highest antagonistic activity...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Parafati L, Vitale A, Restuccia C, Cirvilleri G Tags: Food Microbiol Source Type: research

High pressure inactivation of Brettanomyces bruxellensis in red wine.
Abstract Brettanomyces bruxellensis ("Brett") is a major spoilage concern for the wine industry worldwide, leading to undesirable sensory properties. Sulphur dioxide, is currently the preferred method for wine preservation. However, due to its negative effects on consumers, the use of new alternative non-thermal technologies are increasingly being investigated. The aim of this study was to determine and model the effect of high pressure processing (HPP) conditions and yeast strain on the inactivation of "Brett" in Cabernet Sauvignon wine. Processing at 200 MPa for 3 min resulted in 5....
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: van Wyk S, Silva FV Tags: Food Microbiol Source Type: research

Hanseniaspora uvarum prolongs shelf life of strawberry via volatile production.
Abstract Gray mold caused by Botrytis cinerea led to severe postharvest losses for strawberry industry. In recent years, some studies have shown that postharvest diseases of strawberry can be controlled by using bacterial, fungal and yeast strains. The yeast strain Hanseniaspora uvarum was shown as an effective antagonist against B. cinerea growth. Here, we further investigated the volatile organic compounds (VOCs) production of H. uvarum and how this could impact on postharvest gray mold control of strawberry. A total of 28 VOCs were detected by GC-MS in the headspace of H. uvarum and strawberry wi...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Qin X, Xiao H, Cheng X, Zhou H, Si L Tags: Food Microbiol Source Type: research

Comparison of PCR assays targeting the multi-copy targets B1 gene and 529  bp repetitive element for detection of Toxoplasma gondii in swine muscle.
Comparison of PCR assays targeting the multi-copy targets B1 gene and 529 bp repetitive element for detection of Toxoplasma gondii in swine muscle. Food Microbiol. 2017 May;63:213-216 Authors: Veronesi F, Santoro A, Milardi GL, Diaferia M, Branciari R, Miraglia D, Cioffi A, Gabrielli S, Ranucci D Abstract The comparison of the sensitivities of two molecular assays designed to target the multi-copy sequences of the Toxoplasma gondii genomic B1 region and 529 bp-RE respectively, in detecting T. gondii in swine muscle was assessed. Diaphragm pillars were obtained from 498 slaughtered pigs ...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Veronesi F, Santoro A, Milardi GL, Diaferia M, Branciari R, Miraglia D, Cioffi A, Gabrielli S, Ranucci D Tags: Food Microbiol Source Type: research

Reassessment of the succession of lactic acid bacteria in commercial cucumber fermentations and physiological and genomic features associated with their dominance.
te-Peril MA Abstract A compositional re-assessment of the microbiota present in commercial cucumber fermentation using culture independent and dependent methods was conducted, with emphasis on lactic acid bacteria (LAB). Two commercial cucumber fermentation tanks were monitored by measuring pH, dissolved oxygen and temperature, and used as sources of samples for microbial plating, genomic DNA extraction and measurement of organic acids and carbohydrates by HPLC. Six additional commercial tanks were included to identify the dominant microorganisms using molecular methods. A comparative analysis of the publically av...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Pérez-Díaz IM, Hayes J, Medina E, Anekella K, Daughtry K, Dieck S, Levi M, Price R, Butz N, Lu Z, Azcarate-Peril MA Tags: Food Microbiol Source Type: research

Application of low frequency pulsed ohmic heating for inactivation of foodborne pathogens and MS-2 phage in buffered peptone water and tomato juice.
Abstract The purpose of this study was to inactivate foodborne pathogens effectively by ohmic heating in buffered peptone water and tomato juice without causing electrode corrosion and quality degradation. Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes were used as representative foodborne pathogens and MS-2 phage was used as a norovirus surrogate. Buffered peptone water and tomato juice inoculated with pathogens were treated with pulsed ohmic heating at different frequencies (0.06-1 kHz). Propidium iodide uptake values of bacterial pathogens were significantly (p 
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Kim SS, Choi W, Kang DH Tags: Food Microbiol Source Type: research

Evaluating the efficacy of beef slaughter line interventions by quantifying the six major non-O157 Shiga toxin producing Escherichia coli serogroups using real-time multiplex PCR.
This study tests a real-time multiplex PCR assay and pooling of the samples to optimize the detection and quantification (prevalence and contamination) of six major non-O157 STEC, regardless of possessing Shiga toxins. To demonstrate the practicality, one large-scale slaughter plant (Plant LS) and one small-scale slaughter plant (Plant SS) located in the Mid-Western USA were sampled, in 2011, before the establishment of 2013 USDA laboratory protocols. Carcasses were sampled at consecutive intervention stations and beef trimmings were collected at the end of the fabrication process. Plant SS had marginally more contaminated...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Kanankege KS, Anklam KS, Fick CM, Kulow MJ, Kaspar CW, Ingham BH, Milkowski A, Döpfer D Tags: Food Microbiol Source Type: research

Impact of NaCl reduction on lactic acid bacteria during fermentation of Nocellara del Belice table olives.
Abstract Table olives are widely consumed worldwide but, due to the presence of NaCl in fermenting brines, they contain high levels of sodium. A promising strategy to lower sodium content is the reduction or substitution of NaCl in brines with other chlorides. However, these procedures may impact safety, spoilage, as well as quality and technological properties, including the evolution and final composition of the fermenting microbiota. In the present work the effects of partially replacing NaCl with KCl in fermenting brines on the microbiological quality of Nocellara del Belice olives produced by Spanish sty...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Zinno P, Guantario B, Perozzi G, Pastore G, Devirgiliis C Tags: Food Microbiol Source Type: research

Rapid and sensitive method to assess human viral pollution in shellfish using infectious F-specific RNA bacteriophages: Application to marketed products.
In this study, an integrated cell culture real-time RT-PCR method has been developed to investigate infectious FRNAPH subgroup prevalence in oysters. This rapid screening method appears more sensitive than E. coli or NoV genome detection, and allows an FRNAPH subgroup present in low concentrations (0.05 PFU/g of oyster) to be detected in the presence of another 1000 times more concentrated, without any dissection step. Its application to marketed oysters (n = 135) over a 1-year period has allowed to identify the winter peak classically described for NoV or FRNAPH accumulation. Infectious FRNAPH were det...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Hartard C, Banas S, Rivet R, Boudaud N, Gantzer C Tags: Food Microbiol Source Type: research

Regulation of the synthesis of pulp degrading enzymes in Bacillus isolated from cocoa fermentation.
This study aims to search for biological signals that modulates Pel production and regulators that influence pel gene expression. Strains were grown to the end of exponential phase in media containing various carbon sources. Pel enzymes production in Bacillus was unaffected by simple sugar content variation up to 2%. Additionally, it appeared that pel gene is not under the control of the most common carbon and pectin catabolism regulators ccpA and kdgR, which could explain the insensitivity of Pel production to carbon source variation. However, a 6-fold decrease in Pel production was observed when bacteria were grown in LB...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Ouattara HG, Reverchon S, Niamke SL, Nasser W Tags: Food Microbiol Source Type: research

Blueberry proanthocyanidins against human norovirus surrogates in model foods and under simulated gastric conditions.
The objective of this study was to evaluate the antiviral effect of B-PAC in model foods (apple juice (AJ) and 2% reduced fat milk) and simulated gastrointestinal fluids against cultivable human norovirus surrogates (feline calicivirus; FCV-F9 and murine norovirus; MNV-1) over 24 h at 37 °C. Equal amounts of each virus (5 log PFU/ml) was mixed with B-PAC (1, 2 and 5 mg/ml) prepared either in AJ, or 2% milk, or simulated gastric fluids and incubated over 24 h at 37 °C. Controls included phosphate buffered saline, malic acid (pH 7.2), AJ, 2% milk or simulated gastric and intestinal ...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Joshi S, Howell AB, D'Souza DH Tags: Food Microbiol Source Type: research

The effect of bacteriophages on the acidification of a vegetable juice medium by microencapsulated Lactobacillus plantarum.
Abstract Starter cultures are increasingly being used for the production of sauerkraut, kimchi and other fermented vegetables. The goal of this study was to determine whether the microencapsulation of a bacterial culture can prevent phage infection during vegetable fermentation. Lactobacillus plantarum HER1325 was microencapsulated in alginate beads. Some beads were used without further processing, while others were freeze-dried prior to testing. Fresh beads (diameter of 2 mm) and dried cultures of the lactobacilli (particle size of 53-1000 μm) were added to a vegetable juice medium (VJM) at 1 &t...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Champagne CP, Moineau S, Lafleur S, Savard T Tags: Food Microbiol Source Type: research

Characterization of microbial population of breba and main crops (Ficus carica) during cold storage: Influence of passive modified atmospheres (MAP) and antimicrobial extract application.
z-Moyano S, Córdoba MG Abstract The purpose of this work was to study the changes of bacterial and fungal population of breba fruits such as 'Banane' and 'San Antonio' as well as 'Cuello Dama Negro', 'Cuello Dama Blanco' and 'San Antonio' fig cultivars stored in passive modified atmospheres (MAP) by the use of three different microperforated films (M10 with 16 holes; M30 with five holes and M50 with three holes). Moreover the effects of the application of aqueous soy polyphenolic antimicrobial extract (APE), alone or combined with MAP, were also studied for 'Cuello Dama Negro' and 'Cuello Dama Blanco' fig c...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Villalobos MD, Serradilla MJ, Martín A, Hernández-León A, Ruíz-Moyano S, Córdoba MG Tags: Food Microbiol Source Type: research

Genome comparison and physiological characterization of eight Streptococcus thermophilus strains isolated from Italian dairy products.
Abstract Eight Streptococcus thermophilus strains of dairy origin isolated in Italy were chosen to investigate autochthonous bacterial diversity in this important technological species. In the present study a comparative analysis of all the 17 S. thermophilus genomes publicly available was performed to identify the core and the variable genes, which vary among strains from 196 to 265. Additionally, correlation between the isolation site and the genetic distance was investigated at genomic level. Results highlight that the phylogenetic reconstruction differs from the geographical strain distribution. Moreover,...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Vendramin V, Treu L, Campanaro S, Lombardi A, Corich V, Giacomini A Tags: Food Microbiol Source Type: research

Effects of exposure to quaternary-ammonium-based biocides on antimicrobial susceptibility and tolerance to physical stresses in bacteria from organic foods.
aacute;lvez A, Ortega E Abstract In the present study, a collection of 76 biocide-sensitive bacterial strains isolated from organically produced food were adapted by repeated exposure to increasing concentrations of the quaternary ammonium compounds (QACs) benzalkonium chloride (BC) and hexadecylpyridinium chloride (HDP). The sensitivity of both wildtype strains and their corresponding QAC-adapted strains to other biocides and to antibiotics was studied. QAC tolerance increased in 88.2% of strains for BC and in 30.3% of strains for HDP, with increases in minimum inhibitory concentrations between 2 and over 100 fol...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Gadea R, Fernández Fuentes MÁ, Pérez Pulido R, Gálvez A, Ortega E Tags: Food Microbiol Source Type: research

Detection of premature stop codons leading to truncated internalin A  among food and clinical strains of Listeria monocytogenes.
In this study, 22 L. monocytogenes strains collected in Portugal from the processing environment of a bakery industry (n = 1), different food products (n = 10) and human clinical cases (n = 11) were analysed for mutations in inlA and invasion efficiency in Caco-2 cells. Sequencing revealed previously reported mutations types leading to PMSCs in three food and one clinical strain presenting different molecular serotypes (i.e., IIa, IIb and IIc). The remaining 18 isolates did not show PMSCs in inlA. The four strains with PMSCs in inlA presented lower invasiveness efficiencies in Caco-2...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Ferreira da Silva M, Ferreira V, Magalhães R, Almeida G, Alves A, Teixeira P Tags: Food Microbiol Source Type: research

Effect of osmotic dehydration of olives as pre-fermentation treatment and partial substitution of sodium chloride by monosodium glutamate in the fermentation profile of Kalamata natural black olives.
This study examined the effect of osmotic dehydration of Kalamata natural black olives as pre-fermentation treatment in combination with partial substitution of NaCl by monosodium glutamate (MSG) on the fermentation profile of olives. Osmotic dehydration was undertaken by immersing the olives in 70% (w/w) glucose syrup overnight at room temperature. Further on, three different mixtures of NaCl and MSG with/without prior osmotic dehydration of olives were investigated, namely (i) 6.65% NaCl - 0.35% MSG (5% substitution), (ii) 6.30% NaCl - 0.70% MSG (10% substitution), (iii) 5.95% NaCl - 1.05% MSG (15% substitution), and (iv...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Bonatsou S, Iliopoulos V, Mallouchos A, Gogou E, Oikonomopoulou V, Krokida M, Taoukis P, Panagou EZ Tags: Food Microbiol Source Type: research

Fate of the microbial population and the physico-chemical parameters of "Sanganel" a typical blood sausages of the Friuli, a north-east region of Italy.
Fate of the microbial population and the physico-chemical parameters of "Sanganel" a typical blood sausages of the Friuli, a north-east region of Italy. Food Microbiol. 2017 May;63:84-91 Authors: Iacumin L, Manzano M, Stella S, Comi G Abstract In Friuli, a Northeastern region of Italy, a blood sausage called Sanganel is produced by farmers, butchers, shops, and factories. This sausage is made with pork meat, boiled blood, lard, spices, and salt. It is stored at 4 ± 2 °C and usually eaten fresh or boiled within 14 days of its manufacture. Little is known about its mi...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Iacumin L, Manzano M, Stella S, Comi G Tags: Food Microbiol Source Type: research

Cloning the putative gene of vinyl phenol reductase of Dekkera bruxellensis in Saccharomyces cerevisiae.
Abstract Vinylphenol reductase of Dekkera bruxellensis, the characteristic enzyme liable for "Brett" sensory modification of wine, has been recently recognized to belong to the short chain dehydrogenases/reductases family. Indeed, a preliminary biochemical characterisation has conferred to the purified protein a dual significance acting as superoxide dismutase and as a NADH-dependent reductase. The present study aimed for providing a certain identification of the enzyme by cloning the VPR gene in S. cerevisiae, a species not producing ethyl phenols. Transformed clones of S. cerevisiae resulted ...
Source: Food Microbiology - January 5, 2017 Category: Food Science Authors: Romano D, Valdetara F, Zambelli P, Galafassi S, De Vitis V, Molinari F, Compagno C, Foschino R, Vigentini I Tags: Food Microbiol Source Type: research

Novel PCR-RFLP system based on rpoB gene for differentiation of Cronobacter species.
In this study, we present a novel PCR-RFLP-based method that uses a newly designed pair of primers for the PCR-amplification of a partial rpoB gene sequence (1635 bp). The amplified products of DNA from 80 Cronobacter strains were separately digested with three restriction endonucleases (Csp6I, HinP1I, MboI). Using the obtained restriction patterns, a PCR-RFLP identification system was created to enable differentiation between all seven currently-known Cronobacter species. The functionality of our method was successfully verified on real food samples. Moreover, the relationships between the Cronobacter species were de...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Vlach J, Javůrková B, Karamonová L, Blažková M, Fukal L Tags: Food Microbiol Source Type: research

Characterization of the microbiota in lightly salted bighead carp (Aristichthys nobilis) fillets stored at 4  °C.
Characterization of the microbiota in lightly salted bighead carp (Aristichthys nobilis) fillets stored at 4 °C. Food Microbiol. 2017 Apr;62:106-111 Authors: Liu X, Zhang Y, Li D, Luo Y Abstract The microbiota of unsalted and salted (dry-cured with 2% salt) bighead carp (Aristichthys nobilis) fillets during storage at 4 °C were identified by 16S rRNA gene analysis. Eleven genera were present in the initial microbiota of bighead carp fillets, where Acinetobacter, Aeromonas and Kocuria were the dominant bacteria. As storage time progressed, the microbial composition of both unsalted an...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Liu X, Zhang Y, Li D, Luo Y Tags: Food Microbiol Source Type: research

Microbial decontamination of onion powder using microwave-powered cold plasma treatments.
Abstract The effects of microwave-integrated cold plasma (CP) treatments against spores of Bacillus cereus and Aspergillus brasiliensis and Escherichia coli O157:H7 on onion powder were investigated. The growth of B. cereus, A. brasiliensis, and E. coli O157:H7 in the treated onion powder was assessed during storage at 4 and 25 °C, along with the physicochemical and sensory properties of the powder. Onion powder inoculated with B. cereus was treated with CP using helium as a plasma-forming gas, with simultaneous exposure to low microwave density at 170 mW m(-2) or high microw...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Kim JE, Oh YJ, Won MY, Lee KS, Min SC Tags: Food Microbiol Source Type: research

405  ± 5 nm light emitting diode illumination causes photodynamic inactivation of Salmonella spp. on fresh-cut papaya without deterioration.
This study evaluated the antibacterial effect of 405 ± 5 nm light emitting diode (LED) illumination against four Salmonella serovars on fresh-cut papaya and on fruit quality at various storage temperatures. To determine the antibacterial mechanism of LED illumination at 0.9 kJ/cm(2), oxidative damage to DNA and membrane lipids of Salmonella in phosphate-buffered saline solution was measured. The populations of Salmonella on cut fruits were significantly (P 
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Kim MJ, Bang WS, Yuk HG Tags: Food Microbiol Source Type: research

Development and application of a quantitative real-time PCR assay for rapid detection of the multifaceted yeast Kazachstania servazzii in food.
This study highlights that this newly developed quantitative assay is not only sufficiently sensitive, specific and reliable to be functionally used in food control as a routine method of detection, but also promising in specific studies that seek to further characterize the dynamic of this yeast in some increasingly popular food processes. PMID: 27889139 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Spanoghe M, Godoy Jara M, Rivière J, Lanterbecq D, Gadenne M, Marique T Tags: Food Microbiol Source Type: research

Genotyping of methicillin-resistant Staphylococcus aureus (MRSA) isolated from milk and dairy products in South Italy.
This study aimed to determine the occurrence and the characteristics of MRSA isolated from 3760 samples of milk and dairy products in a previous survey conducted in southern Italy during 2008-2014. Overall out of 484 S. aureus strains isolated, 40 (8.3%) were MRSA and were characterized by spa-typing, Multi-Locus Sequence Typing, SCCmec typing, Staphylococcal enterotoxins (SEs) genes, Panton-Valentine Leukocidin (PVL) genes and ability to form biofilm. The most frequently recovered STs were ST152 (t355-67.5%), followed by ST398 (t899, t108-25%), ST1 (t127-5%) and ST5 (t688-2.5%). All isolates harboured the SCCmec type...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Basanisi MG, La Bella G, Nobili G, Franconieri I, La Salandra G Tags: Food Microbiol Source Type: research

Exploring lot-to-lot variation in spoilage bacterial communities on commercial modified atmosphere packaged beef.
ltman J Abstract Understanding the factors influencing meat bacterial communities is important as these communities are largely responsible for meat spoilage. The composition and structure of a bacterial community on a high-O2 modified-atmosphere packaged beef product were examined after packaging, on the use-by date and two days after, to determine whether the communities at each stage were similar to those in samples taken from different production lots. Furthermore, we examined whether the taxa associated with product spoilage were distributed across production lots. Results from 16S rRNA amplicon sequencing sh...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Säde E, Penttinen K, Björkroth J, Hultman J Tags: Food Microbiol Source Type: research

The microbiota of marketed processed edible insects as revealed by high-throughput sequencing.
Abstract Entomophagy has been linked to nutritional, economic, social and ecological benefits. However, scientific studies on the potential safety risks in eating edible insects need to be carried out for legislators, markets and consumers. In this context, the microbiota of edible insects deserves to be deeply investigated. The aim of this study was to elucidate the microbial species occurring in some processed marketed edible insects, namely powdered small crickets, whole dried small crickets (Acheta domesticus), whole dried locusts (Locusta migratoria), and whole dried mealworm larvae (Tenebrio molitor), throug...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Garofalo C, Osimani A, Milanović V, Taccari M, Cardinali F, Aquilanti L, Riolo P, Ruschioni S, Isidoro N, Clementi F Tags: Food Microbiol Source Type: research

Use of natural antimicrobials to improve the quality characteristics of fresh "Phyllo" - A dough-based wheat product - Shelf life assessment.
This study explores the effects of chitosan and natamycin on the quality of fresh "Phyllo" - a dough-based wheat product, by monitoring the microbiological, physicochemical and sensory parameters. Four different lots of phyllo samples stored under aerobic packaging conditions, in the absence or presence of the aforementioned antimicrobials, were prepared and stored at 4 °C. Microbiological data suggested that, the combination of chitosan and natamycin resulted in significant reductions (1-3 log cfu/g) of the microbial species examined (mesophilic total viable counts; TVC), yeasts/molds, psychro...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Tsiraki MI, Karam L, Abiad MG, Yehia HM, Savvaidis IN Tags: Food Microbiol Source Type: research

Exploring the microbiota of the red-brown defect in smear-ripened cheese by 454-pyrosequencing and its prevention using different cleaning systems.
Abstract Red-brown pigmentation can occasionally form in smeared-ripened cheese such as Fontina during the ripening process. This reaction is due to over-development of the typical microbiota present on the rind. Previous studies have demonstrated the relationship between red-brown pigmentation and the traditional utilization of wooden shelves during cheese ripening. The first part of the paper focuses on the characterisation of yeast and bacterial microbiota: plate counts and 454-pyrosequencing were performed in spoiled (n = 6) and non-spoiled cheeses (n = 6) and on the wooden shelves used dur...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Guzzon R, Carafa I, Tuohy K, Cervantes G, Vernetti L, Barmaz A, Larcher R, Franciosi E Tags: Food Microbiol Source Type: research

Potential probiotic Pichia kudriavzevii strains and their ability to enhance folate content of traditional cereal-based African fermented food.
Abstract With the aim of selecting starter cultures with interesting probiotic potential and with the ability to produce folate in a food matrix, yeast strains isolated from fermented cereal-based African foods were investigated. A total of 93 yeast strains were screened for their tolerance to pH 2 and 0.3% of bile salts. Pichia kudriavzevii isolates gave the best results. Selected P. kudriavzevii strains were tested for survival to the simulated human digestion and for adhesion to Caco-2 cells. Moreover, presence of folate biosynthesis genes was verified and production of extra and intra-cellular folate dete...
Source: Food Microbiology - November 29, 2016 Category: Food Science Authors: Greppi A, Saubade F, Botta C, Humblot C, Guyot JP, Cocolin L Tags: Food Microbiol Source Type: research