Dynamic modelling of brewers' yeast and Cyberlindnera fabianii co-culture behaviour for steering fermentation performance.
Abstract Co-cultivation of brewers' yeast (Saccharomyces cerevisiae) with Cyberlindnera fabianii makes it possible to steer aroma and alcohol levels by changing the inoculation ratio of the two yeasts. A dynamic model was developed based on mono-culture performance of brewers' yeast and C. fabianii in controlled bioreactors with aerated wort as medium, describing growth rate, carbohydrate utilization, ethanol production, maintenance, oxygen consumption and ergosterol biosynthesis/use for cell membrane synthesis (the last one only for brewers' yeast). The parameters were estimated by fitting models to experimental ...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: van Rijswijck IMH, van Mastrigt O, Pijffers G, Wolkers-Rooijackers JCM, Abee T, Zwietering MH, Smid EJ Tags: Food Microbiol Source Type: research

Influence of cell-cell contact between L. thermotolerans and S. cerevisiae on yeast interactions and the exo-metabolome.
This study shows that cell-cell contact not only affects cell viability, as already reported, but markedly affects yeast metabolism. PMID: 31202403 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Petitgonnet C, Klein GL, Roullier-Gall C, Schmitt-Kopplin P, Quintanilla-Casas B, Vichi S, Julien-David D, Alexandre H Tags: Food Microbiol Source Type: research

Ochratoxin A production by Aspergillus westerdijkiae in Italian-type salami.
Abstract The occurrence of ochratoxin A (OTA) in matured meat products can be attributed to mycotoxin coming from raw materials and/or molds that develop on the product surface during ripening. This work aimed to evaluate OTA production by Aspergillus westerdijkiae inoculated on the surface of sausages and its diffusion into the product throughout ripening, study the effect of relative humidity (RH) on the production of this mycotoxin, and investigate the presence of OTA in dry fermented sausages that naturally present intense contamination by A. westerdijkiae. Italian-type sausages were surface inoculated with A....
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Parussolo G, Oliveira MS, Garcia MV, Bernardi AO, Lemos JG, Stefanello A, Mallmann CA, Copetti MV Tags: Food Microbiol Source Type: research

Comparison of bacterial diversity in traditionally homemade paocai and Chinese spicy cabbage.
This study aimed to investigate bacterial diversity in paocai and Chinese spicy cabbage and compare the microbial communities using high-throughput sequencing. Bacteria representing 26 phyla, 480 genera and 338 species were observed in these Chinese fermented vegetables. Firmicutes and Proteobacteria were the main phyla observed in both paocai and Chinese spicy cabbage. Additionally, Lactobacillus, Pediococcus, Serratia, Stenotrophomonas and Weissella were the major genera observed in both paocai and Chinese spicy cabbage. Overall, the relative abundances of Lactobacillus, Pediococcus and Weissella in Chinese spicy cabbage...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Liu Z, Peng Z, Huang T, Xiao Y, Li J, Xie M, Xiong T Tags: Food Microbiol Source Type: research

Resistance of thermophilic spore formers isolated from milk and whey products towards cleaning-in-place conditions: Influence of pH, temperature and milk residues.
This study aims to investigate the resistance of thermophilic endospores towards cleaning solutions typically used for cleaning-in-place in dairy manufacturing plants. From eleven tested strains, all were able to survive an alkaline treatment (NaOH) at 65 °C for 10 min (0.5%), whereas at concentrations of 2% eight strains withstood the treatment. Acid solutions were more sporicidal. At 0.5% of HNO3, only three strains survived the treatment. Milk impurities reduced the inactivation effect of the NaOH solutions towards thermophilic spore formers. For two selected strains, a detailed kinetic inactivation in NaOH and ...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Wedel C, Wenning M, Dettling A, Scherer S, Hinrichs J Tags: Food Microbiol Source Type: research

Strawberry sanitization by peracetic acid washing and its effect on fruit quality.
T, Viñas I Abstract The risk posed by outbreaks associated with strawberries together with the safety issues of by-products from chlorine disinfection in the fruit industry has led to a search for alternative sanitizers. The disinfection capacity of peracetic acid (PA) at three concentrations (20, 40 and 80 ppm) and washing times (1 and 2 min) was compared to sodium hypochlorite (200 ppm) (NaClO) treatments and a water control, and its influence on the physico-chemical, biochemical and nutritional quality of strawberries was also studied. Counts on total aerobic mesophilic microorganisms were comparab...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Nicolau-Lapeña I, Abadias M, Bobo G, Aguiló-Aguayo I, Lafarga T, Viñas I Tags: Food Microbiol Source Type: research

Evaluation of storage conditions and efficiency of a novel microencapsulated Salmonella phage cocktail for controlling S. enteritidis and S. typhimurium in-vitro and in fresh foods.
In this study, microencapsulation is applied for enhancing the stability and efficacy of phages as bio-control agent. Microencapsulated phage cocktail kept in aluminium laminated foil bag (LF) at 4 °C showed the highest survivability with a titer loss of 0.5 log PFU/g after 12 weeks of storage. Titer loss of phage cocktail lysate>4 log PFU/mL was observed after 12 weeks, at 4 °C. Color change of microencapsulated phage cocktail kept in LF at 4 °C did not show any significant difference during storage, and water activity (free water content) at 0.13 was found in these conditions. In-vitro study, S. Ente...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Petsong K, Benjakul S, Vongkamjan K Tags: Food Microbiol Source Type: research

Impact of temperature and oxygen on the fate of Bacillus weihenstephanensis in a food-based medium.
The C Abstract The capacity of the Bacillus weihenstephanensis KBAB4 strain, a psychrotolerant species of the B. cereus sensu lato group, to multiply in carrot broth at 8 °C and 30 °C, in presence or absence of oxygen was determined. In aerobic carrot broth tyndallized in presence of oxygen, at both temperatures, the population of vegetative cells of B. weihenstephanensis inoculated at a level of 103 or 106 CFU/ml dropped immediately. After 16 h at 30 °C, B. weihenstephanensis reached around 103 CFU/ml, indicating that some vegetative cells had survived and multiplied, with lipid inclusio...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Guérin A, Dargaignaratz C, Clavel T, Broussolle V, Nguyen-The C Tags: Food Microbiol Source Type: research

Contamination of yellow-feathered broiler carcasses: Microbial diversity and succession during processing.
This study investigated the effect of processing water and processing time on the microbial diversity of yellow-feathered broiler carcasses at select stages of slaughter during one commercial processing day using a high-throughput sequencing technique targeting the V3V4 region of the 16S RNA gene. Our results demonstrated that Firmicutes and Proteobacteria were the dominant bacterial phyla of broiler carcasses and processing water in the chiller tank, whereas the processing water in the scalder tank contained a high abundance of Firmicutes and Deinococcus-Thermus. At the genus level, Escherichia-Shigella and Streptococcus ...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Wang H, Qin X, Mi S, Li X, Wang X, Yan W, Zhang C Tags: Food Microbiol Source Type: research

Selection of a new Saccharomyces yeast to enhance relevant sorghum beer aroma components, higher alcohols and esters.
Abstract The selection of Saccharomyces yeast which is able to produce high amounts of relevant aroma components from sorghum wort has been scarcely explored. Furthermore, generating sorghum beer with low levels of vicinal diketones (VDKs) is a permanent concern of brewers because of the wort's low amino acid content. To address these challenges, a performant Saccharomyces cerevisiae yeast was selected based on the higher alcohols and esters it synthesizes, and conditions influencing the young beer's VDK content were studied. Our results confirm that the low amino acid content limits aromagenesis by industrial ale...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Tokpohozin SE, Fischer S, Becker T Tags: Food Microbiol Source Type: research

Assessment of Pediococcus acidilactici ATCC 8042 as potential Salmonella surrogate for thermal treatments of toasted oats cereal and peanut butter.
The objective of this study was to evaluate the use of Pediococcus acidilactici ATCC 8042, a generally recognized as safe bacterium (GRAS), as potential surrogate for Salmonella in commercial toasted oats cereal (TOC) and peanut butter. P. acidilactici was compared to a five-serovar cocktail of Salmonella and Enterococcus faecium NRRL-B2354, separately. Cultures were inoculated into TOC and thermal kinetic parameters (δ, β) were determined at 80, 85, 90, and 95 °C using the Weibull model. In peanut butter, δ and β parameters were obtained at 63, 68, 73, and 77 °C. In TOC, the δ value...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Deen B, Diez-Gonzalez F Tags: Food Microbiol Source Type: research

Biofilm formation, virulence and antimicrobial resistance of different Campylobacter jejuni isolates from a poultry slaughterhouse.
I, Rovira J Abstract The fastidious requirement of the zoonotic pathogen Campylobacter jejuni contrasts with its ability to overcome harsh conditions. Different strategies might be involved in the survival and persistence of C. jejuni through the poultry food chain. Therefore, the aims of this study were to get insights in the survival strategies in the poultry slaughterhouse environment by (i) characterizing factors such as biofilm formation, virulence and antimicrobial resistance in environmental isolates and (ii) understanding the possible link between the phenotypic and genetic characterization using whole gen...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: García-Sánchez L, Melero B, Jaime I, Rossi M, Ortega I, Rovira J Tags: Food Microbiol Source Type: research

Variation of microbial load and biochemical activity of ready-to-eat salads in Cyprus as affected by vegetable type, season, and producer.
Abstract Fresh vegetables are important components of an everyday balanced diet making ready to-eat-salads (RTE) a commodity widely consumed. However, in the past few years these products have been linked with outbreaks of salmonellosis and listeriosis; thus the continuous investigation of their safety is an essential requirement. A total of 216 samples of ready-to-eat salads from the Cypriot market were analysed to determine the microbiological quality and safety, along with physicochemical attributes of the salads and identify possible correlations between them. The samples were randomly collected from four reta...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Xylia P, Botsaris G, Chrysargyris A, Skandamis P, Tzortzakis N Tags: Food Microbiol Source Type: research

Association of fungal genera from spoiled processed foods with physicochemical food properties and processing conditions.
This study was designed to evaluate the influence of intrinsic and extrinsic food product variables on the identity of spoilage fungi genera isolated from commercially produced foods. The spoilage etiology was identified in 127 products through ITS region sequencing. The prevalence and diversity of the identified spoilage fungi were evaluated in relationship to product-specific attributes using various descriptive statistics and a bipartite network analysis. Additionally, recursive partitioning was used to generate a classification tree with the outcomes, genera of the spoilage isolates, divided into increasingly homogenou...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Snyder AB, Churey JJ, Worobo RW Tags: Food Microbiol Source Type: research

Effect of ε-polylysine and ice storage on microbiota composition and quality of Pacific white shrimp (Litopenaeus vannamei) stored at 0 °C.
In conclusion, ε-Polylysine and ice storage altered the microbiota composition and delayed quality deterioration of Pacific white shrimp. PMID: 31202416 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Jia S, Liu Y, Zhuang S, Sun X, Li Y, Hong H, Lv Y, Luo Y Tags: Food Microbiol Source Type: research

Genomic and metabolic features of Tetragenococcus halophilus as revealed by pan-genome and transcriptome analyses.
Abstract The genomic and metabolic diversity and features of Tetragenococcus halophilus, a moderately halophilic lactic acid bacterium, were investigated by pan-genome, transcriptome, and metabolite analyses. Phylogenetic analyses based on the 16S rRNA gene and genome sequences of 15 T. halophilus strains revealed their phylogenetic distinctness from other Tetragenococcus species. Pan-genome analysis of the T. halophilus strains showed that their carbohydrate metabolic capabilities were diverse and strain dependent. Aside from one histidine decarboxylase gene in one strain, no decarboxylase gene associated with bi...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Chun BH, Han DM, Kim KH, Jeong SE, Park D, Jeon CO Tags: Food Microbiol Source Type: research

Farm-to-fork profiling of bacterial communities associated with an artisan cheese production facility.
The objective of this study was to investigate the microbiota from dairy farm to final cheeses along an artisanal cheese-making continuum. Environmental and food samples were collected from 21 sites, including the dairy farm, milk, cheese plant, and finished cheeses. The microbiota of these samples were analyzed using 16S rRNA amplicon sequencing, with sequences grouped into operational taxonomic units (OTUs) by phylotype at the genus level. Alpha diversity decreased from dairy farm to finished cheese. Firmicutes was the dominant phylum, ranging from 31% to 92% between the dairy farm and finished cheeses, respectively, wit...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Falardeau J, Keeney K, Trmčić A, Kitts D, Wang S Tags: Food Microbiol Source Type: research

Antifungal activity of commercial sanitizers against strains of Penicillium roqueforti, Penicillium paneum, Hyphopichia burtonii, and Aspergillus pseudoglaucus: Bakery spoilage fungi.
Abstract Information on the sensitivity of spoilage fungi of bakery products to sanitizing agents is scarce in the literature. Thus, the aim of this study was to evaluate the antifungal activity of different classes of commercial sanitizers, which have permitted use in the food industry, on the main fungi involved in spoiling bakery products. The tests were carried out according to the protocol for testing the antifungal effect of chemical sanitizers of the European Committee for Standardization (CEN), with adaptations. Different strains of six isolated fungal species responsible for spoiling bakery products (Peni...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Bernardi AO, Stefanello A, Lemos JG, Garcia MV, Copetti MV Tags: Food Microbiol Source Type: research

Assessment of the bioprotective potential of lactic acid bacteria against Listeria monocytogenes on vacuum-packed cold-smoked salmon stored at 8  °C.
In this study, we evaluated the following three potential bioprotective lactic acid bacterial strains against L. monocytogenes in three smoked salmon types with different physicochemical characteristics, primarily fat, moisture, phenol and acid acetic content: two bacteriocin-like producers that were isolated from smoked salmon and identified as Lactobacillus curvatus and Carnobacterium maltaromaticum and a recognized bioprotective bacteriocin producer from meat origin, Lactobacillus sakei CTC494. L. sakei CTC494 inhibited the growth of L. monocytogenes after 21 days of storage at 8 °C in all the products tested, whe...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Aymerich T, Rodríguez M, Garriga M, Bover-Cid S Tags: Food Microbiol Source Type: research

Influence of nitrogen status in wine alcoholic fermentation.
dre H Abstract Nitrogen is an essential nutrient for yeast during alcoholic fermentation. Nitrogen is involved in the biosynthesis of protein, amino acids, nucleotides, and other metabolites, including volatile compounds. However, recent studies have called several mechanisms that regulate its role in biosynthesis into question. An initial focus on S. cerevisiae has highlighted that the concept of "preferred" versus "non-preferred" nitrogen sources is extremely variable and strain-dependent. Then, the direct involvement of amino acids consumed in the formation of proteins and volatile compounds...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Gobert A, Tourdot-Maréchal R, Sparrow C, Morge C, Alexandre H Tags: Food Microbiol Source Type: research

High-throughput sequencing analysis of bacterial community composition and quality characteristics in refrigerated pork during storage.
This study provides insight into the determinants of shelf life. Furthermore, it provides insight into the process involved in refrigerated pork spoilage. PMID: 31202422 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Li N, Zhang Y, Wu Q, Gu Q, Chen M, Zhang Y, Sun X, Zhang J Tags: Food Microbiol Source Type: research

Growth/no-growth models of in-vitro growth of Penicillium paneum as a function of thyme essential oil, pH, aw, temperature.
Abstract The aims of this study were (i) screening of antifungal activity of thyme essential oil on Penicillium paneum; (ii) development of growth/no-growth models (G/NG); and (iii) validation of the G/NG models by performing bread baking trials. The screening method was based on the measurement of fungal growth in a semi-solid medium through optical density. The combined influence of aw (0.88-0.97), pH (4.8-7.0), temperature (22 and 30 °C), time (0-144 h) and varying concentrations of thyme oil (0-2 μL/mL YES) were assessed. Growth of P. paneum at aw 0.88 was significantly reduced compared to aw 0.93...
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Debonne E, Vermeulen A, Van Bockstaele F, Soljic I, Eeckhout M, Devlieghere F Tags: Food Microbiol Source Type: research

An ordinal logistic regression approach to predict the variability on biofilm formation stages by five Salmonella enterica strains on polypropylene and glass surfaces as affected by pH, temperature and NaCl.
This study assessed the adhesion and formation of biofilm by five Salmonella enterica strains (S. Enteritidis 132, S. Infantis 176, S. Typhimurium 177, S. Heidelberg 281 and S. Corvallis 297) on polypropylene (PP) and glass (G) surfaces as affected by pH (4-7), NaCl concentration (0-10% w/v) and temperature (8-35 °C). Sessile counts 4% and at a temperature
Source: Food Microbiology - June 18, 2019 Category: Food Science Authors: Moraes JO, Cruz EA, Pinheiro Í, Oliveira TCM, Alvarenga V, Sant'Ana AS, Magnani M Tags: Food Microbiol Source Type: research

Traceability of different brands of bottled mineral water during shelf life, using PCR-DGGE and next generation sequencing techniques.
In conclusion, no differences in total, viable and culturable bacteria counts were observed between mineral waters bottled with PET or glass during shelf life storage. Nevertheless, in spite of changes in the communities, each water brand and material presented a distinct microbial community structure clearly distinguishable from the others, which could be interesting for traceability purposes. PMID: 31027761 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Sala-Comorera L, Blanch AR, Casanovas-Massana A, Monleón-Getino A, García-Aljaro C Tags: Food Microbiol Source Type: research

Oxacillin-susceptible mecA-positive Staphylococcus aureus associated with processed food in Europe.
We report for the first time an oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) associated with a processed food product in Europe. One isolate (MRSA-ST5-type V SCCmec) was found in cheese among 600 food samples confiscated from air passengers from international flights in Vienna Airport (Austria). Type V SCCmec strains do not harbor functional mecI-mecR1 genes and in such strains mecA expression is regulated by the bla system (blaI-blaR1-blaZ). It has been recently reported that malfunctions in the bla system lead to the constitutive expression of mecA. The OS-MRSA reported in this study harbored the b...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Quijada NM, Hernández M, Oniciuc EA, Eiros JM, Fernández-Natal I, Wagner M, Rodríguez-Lázaro D Tags: Food Microbiol Source Type: research

Species identification and molecular characterization of Cronobacter spp. isolated from food imported over nine years into Beijing, China.
In conclusion, appropriate in-house database could make MALDI-TOF MS method identifying Cronobacter spp. isolates to the species level. But the spectra data were not sufficiently consistent for subtyping, unlike MLST. The Cronobacter spp. isolates have a high diversity including recognized pathovars. PMID: 31027763 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Wang Q, Forsythe SJ, Zhao XJ, Wang ZW, Li D, Ma D, Cao JY, Zeng J Tags: Food Microbiol Source Type: research

Potential of acidified sodium benzoate as an alternative wash solution of cherry tomatoes: Changes of quality, background microbes, and inoculated pathogens during storage at 4 and 21 °C post-washing.
Potential of acidified sodium benzoate as an alternative wash solution of cherry tomatoes: Changes of quality, background microbes, and inoculated pathogens during storage at 4 and 21°C post-washing. Food Microbiol. 2019 Sep;82:111-118 Authors: Chen H, Zhang Y, Zhong Q Abstract To evaluate the feasibility of acidified sodium benzoate (NaB) as alternative washing solutions of fresh produce, the survival of inoculated pathogens, the background molds and yeasts counts, and quality parameters were compared during 4 and 21 °C storage of cherry tomatoes washed with 3000 ppm NaB at pH 2.0, 200 ...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Chen H, Zhang Y, Zhong Q Tags: Food Microbiol Source Type: research

Surveillance of norovirus contamination in commercial fresh/frozen berries from Heilongjiang Province, China, using a TaqMan real-time RT-PCR assay.
This study highlights the need for further risk surveillance for NoV contamination in berries produced in the Heilongjiang Province and recommends region-extended monitoring of retail berries for NoV. PMID: 31027765 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Gao X, Wang Z, Wang Y, Liu Z, Guan X, Ma Y, Zhou H, Jiang Y, Cui W, Wang L, Xu Y Tags: Food Microbiol Source Type: research

Effects of pulsed light and sanitizer wash combination on inactivation of Escherichia coli O157:H7, microbial loads and apparent quality of spinach leaves.
Abstract The purpose of this study was to investigate the efficacy of pulsed light (PL), a new formula of sanitizer (HEN) consisting of hydrogen peroxide, EDTA and Nisin, as well as synergy of PL and HEN sanitizer (PL-HEN) wash in inactivating E. coli O157:H7 on spinach. The treatment effect on microbial loads and apparent quality during 13 days storage at 4 °C was also determined. A bacterial cocktail containing three strains of E. coli O157:H7 was used as inoculum based on their association with produce-related outbreaks. Spinach leaves were spot inoculated on surface before treating with PL (1-63J/cm2), H...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Mukhopadhyay S, Sokorai K, Ukuku DO, Fan X, Olanya M, Juneja V Tags: Food Microbiol Source Type: research

Evaluation of Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella during cocoa powder thermal processing.
Abstract Salmonella is capable of surviving in a low moisture environment for long periods. Once adapted to the xeric conditions, the thermal resistance of Salmonella is enhanced. Cocoa powder is a low water activity (aw) food (LawF) that is an essential component in a wide variety of desserts and ready-to-eat (RTE) foods and drinks. The aim of this study was to evaluate the desiccation and thermal resistance of Salmonella in cocoa powder, as well as to examine the suitability of Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella during cocoa powder thermal processing. Natural unsweetened cocoa powder ...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Tsai HC, Ballom KF, Xia S, Tang J, Marks BP, Zhu MJ Tags: Food Microbiol Source Type: research

Effects of the colonization sequence of Listeria monocytogenes and Pseudomonas fluorescens on survival of biofilm cells under food-related stresses and transfer to salmon.
This study evaluated how the colonization sequence of Listeria monocytogenes and Pseudomonas fluorescens affects biofilm formation and biofilm cell response to food-related stress (desiccation or disinfection) as well as the transferability of L. monocytogenes to salmon products. The results showed that the colonization sequence did not affect the population of dual species biofilms. Furthermore, survival number of L. monocytogenes was 0.8 log CFU/cm2 higher when P. fluorescens was the first colonizer during desiccation or disinfectant treatment in comparison with dual-species biofilms with other colonization sequences. A ...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Pang X, Yuk HG Tags: Food Microbiol Source Type: research

Aroma formation in retentostat co-cultures of Lactococcus lactis and Leuconostoc mesenteroides.
This study provides insights in the production of cheese aroma compounds outside the cheese matrix by co-cultures of L. lactis and Lc. mesenteroides, which could be used as food supplements in dairy or non-dairy products. PMID: 31027769 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: van Mastrigt O, Egas RA, Abee T, Smid EJ Tags: Food Microbiol Source Type: research

Selection of Algerian lactic acid bacteria for use as antifungal bioprotective cultures and application in dairy and bakery products.
Abstract In the context of a demand for "preservative-free" food products, biopreservation appears as a promising alternative to either replace or reduce the use of chemical preservatives. The purpose of this study was to evaluate the antifungal activity of a collection of lactic acid bacteria (n = 194), and then to evaluate the applicability and efficacy of selected ones used as bioprotective cultures against mold spoilers in dairy and bakery products. First, lactic acid bacteria were isolated from various Algerian raw milk samples and Amoredj, a traditional fermented product. Secondly, in vitro scr...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Ouiddir M, Bettache G, Leyva Salas M, Pawtowski A, Donot C, Brahimi S, Mabrouk K, Coton E, Mounier J Tags: Food Microbiol Source Type: research

Effect of 222-nm krypton-chloride excilamp treatment on inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium on alfalfa seeds and seed germination.
We examined the control effect of a 222-nm KrCl excilamp on foodborne pathogens on alfalfa seeds and compared it with a conventional 254-nm low-pressure (LP) Hg lamp. When the 222-nm KrCl excilamp treated seeds at 87, 174 and 261 mJ/cm2, the log reductions of Escherichia coli O157:H7 (E. coli O157:H7) were 0.85, 1.77, and 2.77, respectively, and Salmonella Typhimurium (S. Typhimurium) experienced log reductions of 1.22, 2.27, and 3.04, respectively. When the 254-nm LP Hg lamp was applied at 87, 174, and 261 mJ/cm2, the log reductions of E. coli O157: H7 were 0.7, 1.16, and 1.43, respectively, and those of S. Typhimuriu...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Kang JW, Lee JI, Jeong SY, Kim YM, Kang DH Tags: Food Microbiol Source Type: research

Proteomic analysis of the food spoiler Pseudomonas fluorescens ITEM 17298 reveals the antibiofilm activity of the pepsin-digested bovine lactoferrin.
In conclusion, in this work protein determinats of biofilm formation were revelead in ITEM 17298 under the low temperature; the synthesis of these latter were inhibited by HLF confirming its possible exploitation as antibiofilm agent for biotechnological applications in cold stored foods. PMID: 31027772 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Quintieri L, Zühlke D, Fanelli F, Caputo L, Liuzzi VC, Logrieco AF, Hirschfeld C, Becher D, Riedel K Tags: Food Microbiol Source Type: research

Quantification and genetic diversity of Hepatitis E virus in wild boar (Sus scrofa) hunted for domestic consumption in Central Italy.
This study assessed HEV occurrence, viral load and genetic variability in wild boar hunted for domestic consumption in the district of Viterbo (Central Italy) where high anti-HEV IgG seroprevalence values are reported in humans. A total of 332 liver and 69 intestine samples were obtained from wild boar hunted between 2011 and 2014. The liver tissue in 54 of the animals (16.3%) was HEV-positive. Viral loads in quantifiable liver samples (n = 29) ranged between 3.2 × 102 and 3.8 × 105 genome copies (g.c.)/g with a mean value of 1.85 × 104 g.c./g. A statistically significant positive correlat...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Di Pasquale S, De Santis P, La Rosa G, Di Domenico K, Iaconelli M, Micarelli G, Martini E, Bilei S, De Medici D, Suffredini E Tags: Food Microbiol Source Type: research

Mentha piperita L. essential oil inactivates spoilage yeasts in fruit juices through the perturbation of different physiological functions in yeast cells.
This study evaluated the efficacy of the essential oil from Mentha piperita L. (MPEO) to inactivate cells of the potentially spoilage yeasts Candida albicans, Candida tropicalis, Pichia anomala and Saccharomyces cerevisiae in cashew, guava, mango and pineapple juices during 72 h of refrigerated storage. Damage in different physiological functions caused by MPEO in S. cerevisiae in cashew and guava juices were investigated using flow cytometry (FC). The effects of the incorporation of an effective anti-yeast MPEO dose on sensory characteristics of juices were also evaluated. MPEO displayed minimum inhibitory concentration...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Almeida ETDC, de Souza GT, de Sousa Guedes JP, Barbosa IM, de Sousa CP, Castellano LRC, Magnani M, de Souza EL Tags: Food Microbiol Source Type: research

Antiviral effects of blueberry proanthocyanidins against Aichi virus.
This study aimed to (1) determine the time- and dose-dependent effects of blueberry proanthocyanidins (B-PAC) against AiV over 24 h at 37 °C; (2) gain insights on their mode of action using pre- and post-treatment of host cells and Transmission Electron Microscopy; and (3) determine their anti-AiV effects in model foods and under simulated gastric conditions. AiV at ∼5 log PFU/ml was incubated with equal volumes of commercial blueberry juice (BJ, pH 2.8), neutralized BJ (pH 7.0), B-PAC (2, 4, and 10 mg/ml) prepared either in 10% ethanol, apple juice (AJ), 2% milk, simulated gastric fluid (SGF, pH 1.5) or simu...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Joshi SS, Howell AB, D'Souza DH Tags: Food Microbiol Source Type: research

Bacterial spoilage profiles in the gills of Pacific oysters (Crassostrea gigas) and Eastern oysters (C. virginica) during refrigerated storage.
In this study, the microbial activities and pH changes of the gills of the two species, Crassostrea gigas and C. virginica, harvested from three different sites were determined and sensory evaluation was conducted during refrigerated storage. The bacteria in gills with an initial aerobic plate count (APC) of 3.1-4.5 log CFU/g rose remarkably to 7.8-8.8 log CFU/g after 8-days of storage. The APC of Enterobacteriaceae increased from 2.5 to 3.6 log CFU/g to 4.5-4.8 log CFU/g, and that of lactic acid bacteria (LAB) fluctuated in the range of 1.4-3.0 log CFU/g during the whole storage period. The results of sensory analysis ind...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Chen H, Wang M, Yang C, Wan X, Ding HH, Shi Y, Zhao C Tags: Food Microbiol Source Type: research

Novel solid-state fermentation of bee-collected pollen emulating the natural fermentation process of bee bread.
Abstract Structure of lactic acid bacteria biota in ivy flowers, fresh bee-collected pollen (BCP), hive-stored bee bread, and honeybee gastrointestinal tract was investigated. Although a large microbial diversity characterized flowers and fresh BCP, most of lactic acid bacteria species disappeared throughout the bee bread maturation, giving way to Lactobacillus kunkeei and Fructobacillus fructosus to dominate long stored bee bread and honeybee crop. Adaptation of lactic acid bacteria was mainly related to species-specific, and, more in deep, to strain-specific features. Bee bread preservation seemed related to bac...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Di Cagno R, Filannino P, Cantatore V, Gobbetti M Tags: Food Microbiol Source Type: research

Characterization of plant lectins for their ability to isolate Mycobacterium avium subsp. paratuberculosis from milk.
Deeg CA PMID: 31027778 [PubMed - in process] (Source: Food Microbiology)
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Hobmaier BF, Lutterberg K, Kleinwort KJH, Mayer R, Hirmer S, Amann B, Hölzel C, Märtlbauer EP, Deeg CA Tags: Food Microbiol Source Type: research

Significance of Aspergillus niger aggregate species as contaminants of food products in Spain regarding their occurrence and their ability to produce mycotoxins.
lez-Jaén MT, Patiño B Abstract The Aspergillus niger aggregate contains 15 morphologically indistinguishable species which presence is related to ochratoxin A (OTA) and fumonisin B2 (FB2) contamination of foodstuffs. The taxonomy of this group was recently reevaluated and there is a need of new studies regarding the risk that these species might pose to food security. 258 isolates of A. niger aggregate obtained from a variety of products from Spain were classified by molecular methods being A. tubingensis the most frequently occurring (67.5%) followed by A. welwitschiae (19.4%) and A. niger (11.7%). ...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Gil-Serna J, García-Díaz M, Vázquez C, González-Jaén MT, Patiño B Tags: Food Microbiol Source Type: research

The evaluation of gamma irradiation and cold storage for the reduction of Campylobacter jejuni in chicken livers.
In this study, gamma irradiation is evaluated for its effectiveness in reducing Campylobacter jejuni numbers in experimentally contaminated chicken livers. A wide range of radiation doses were evaluated in conjunction with cold storage parameters, before and after irradiation. Storage of chicken livers at -20 °C prior to radiation treatment, as expected, increased C. jejuni radiation resistance. Livers previously stored at -20 °C exhibited D10 values of 0.748 kiloGray (kGy) compared to livers without previous storage that had a significantly lower D10 value of 0.361 kGy. Cold storage conditions post-irradiati...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Gunther NW, Abdul-Wakeel A, Scullen OJ, Sommers C Tags: Food Microbiol Source Type: research

Characterization of Arcobacter spp. isolated from retail seafood in Germany.
This study aimed to evaluate the presence of Arcobacter in retail seafood and characterize Arcobacter isolates derived from these matrices. In total, seven species of Arcobacter were isolated from 56 of 318 (17.6%) seafood samples, including bivalves (mussels, clams and razor clams), shrimps and cephalopods (squids and octopuses). The highest prevalence was detected in cephalopods (27.4%), followed by bivalves (18%) and lowest in shrimps (8.5%). PCRs of 10 putative virulence genes demonstrated higher prevalences of these genes among A. butzleri, compared to other species, such as A. cryaerophilus, A. aquimarinus and A. ven...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Zhang X, Alter T, Gölz G Tags: Food Microbiol Source Type: research

Microbial biogeography of Spanish-style green olive fermentations in the province of Seville, Spain.
ba JL Abstract The aim of this study is to examine the biogeography of the microbial communities associated to the Spanish-style green olive fermentations in the province of Seville (Andalucía, south-western Spain). Also, to understand how microorganisms colonize and persist in non-sterile food fermentations across a specific table olive producing area, i.e. a specific "agroecosystem". The microbial diversity, bacteria and yeast, in 30 ten-ton fermenters of three different fermentations yards (patios) along the olive fermentation was studied. A total of 951 microbial isolates were obtained which w...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Lucena-Padrós H, Ruiz-Barba JL Tags: Food Microbiol Source Type: research

Biocontrol of aflatoxigenic Aspergillus parasiticus by native Debaryomyces hansenii in dry-cured meat products.
cute;ñez F Abstract Dry-cured meat products, such as dry-cured ham or dry-fermented sausages, are characterized by their particular ripening process, where a mould population grows on their surface. Some of these moulds are hazardous to the consumers because of their ability to produce mycotoxins including aflatoxins (AFs). The use of native yeasts could be considered a potential strategy for controlling the presence of AFs in dry-cured meat products. The aim of this work was to evaluate the antagonistic activity of two native Debaryomyces hansenii strains on the relative growth rate and the AFs production ...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Peromingo B, Andrade MJ, Delgado J, Sánchez-Montero L, Núñez F Tags: Food Microbiol Source Type: research

Application of colony BOXA2R-PCR for the differentiation and identification of lactic acid COCCI.
In this study, it was demonstrated that BOXA2R-PCR could effectively discriminate between Lactococcus lactis, Leuconostoc mesenteroides and Streptococcus thermophilus; differentiate Lactococcus lactis strains and subspeciate them into lactis and cremoris in a single reaction; generate unique strain fingerprints of various lactic acid bacteria (LAB species) commonly isolated from fermented dairy products, including occasional spoilage bacteria and yeasts. Furthermore, using direct colony PCR a reproducible and rapid method was developed for the differentiation and identification of lactic acid cocci. The simplicity and spee...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Damnjanovic D, Harvey M, Bridge WJ Tags: Food Microbiol Source Type: research

MRSA in swine, farmers and abattoir workers in Southern Italy.
In this study, MRSA strains were isolated from 55 of the 85 (64.7%) intensive pig farms surveyed, and prevalence was greater on pig fattening farms than on breeding farms. In addition, we included in the study 63 foreign pigs imported for slaughter. Overall, the prevalence of MRSA in the 418 sampled swine was 59.1%; 12 genotypes were identified among the isolates; ST398 (96.4%) was most prevalent, followed by ST97 (2%), ST9 (0.8%) and ST1 (0.8%). MRSA isolates were also detected in 26 (17.3%) of the 150 operators included in the study; the genotypes detected were ST398 (85%), ST9 (7.6%), ST5 (3.8%) and ST1 (3.8%). All the ...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Parisi A, Caruso M, Normanno G, Latorre L, Miccolupo A, Fraccalvieri R, Intini F, Manginelli T, Santagada G Tags: Food Microbiol Source Type: research

Effect of different starter cultures on chemical and microbial parameters of buckwheat honey fermentation.
ayo B Abstract The aim of this study was to analyze the microbiology of buckwheat honey fermentation inoculated with different starter cultures by culturing and PCR-DGGE, taking as a model for comparison a spontaneously fermented batch. The inoculants tested were (i) cider lees (from a cider factory), (ii) sourdough (from a bakery), and (iii) a commercial Saccharomyces cerevisiae strain. The results of the culturing and culture-independent techniques agreed well and detected the same dominant species along the fermentations. Our results suggest that S. cerevisiae strains, which constituted a majority population in...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Bednarek M, Szwengiel A, Flórez AB, Czarnecki Z, Mayo B Tags: Food Microbiol Source Type: research

Lactococcus lactis subsp. lactis as a natural anti-listerial agent in the mushroom industry.
Abstract Mushroom growth substrates from different commercial producers of mushrooms (Agaricus bisporus) were screened for the presence of bacteria with potential for use as biocontrol agents for controlling Listeria monocytogenes in the mushroom production environment. Eight anti-listerial strains were isolated from different sources and all were identified using 16s rRNA gene sequencing as Lactococcus lactis subsp. lactis. Whole-genome sequencing of the Lc. lactis isolates indicated that strains from different sites and substrate types were highly similar. Colony MALDI-TOF mass spectrometry found that these stra...
Source: Food Microbiology - April 29, 2019 Category: Food Science Authors: Dygico LK, O'Connor PM, Hayes M, Gahan CGM, Grogan H, Burgess CM Tags: Food Microbiol Source Type: research