A Comparative Genomic and Safety Assessment of Six Lactiplantibacillus plantarum subsp. argentoratensis Strains Isolated from Spontaneously Fermented Greek Wheat Sourdoughs for Potential Biotechnological Application.

The comparative genome analysis of six Lactiplantibacillus plantarum subsp. argentoratensis strains previously isolated from spontaneously fermented Greek wheat sourdoughs is presented. Genomic attributes related to food safety have been studied according to the European Food Safety Authority (EFSA) suggestions for the use of lactic acid bacteria (LAB) in the production of foods. Bioinformatic analysis revealed a complete set of genes for maltose, sucrose, glucose, and fructose fermentation; conversion of fructose to mannitol; folate and riboflavin biosynthesis; acetoin production; conversion of citrate to oxaloacetate; and the ability to produce antimicrobial compounds (plantaricins). Pathogenic factors were absent but some antibiotic resistance genes were detected. CRISPR and cas genes were present as well as various mobile genetic elements (MGEs) such as plasmids, prophages, and insertion sequences. The production of biogenic amines by these strains was not possible due to the absence of key genes in their genome except lysine decarboxylase associated with cadaverine; however, potential degradation of these substances was identified due to the presence of a blue copper oxidase precursor and a multicopper oxidase protein family. Finally, comparative genomics and pan-genome analysis showed genetic differences between the strains (e.g., variable pln locus), and it facilitated the identification of various phenotypic and probiotic-related properties.

Evaluation of Plantaricin Genes Expression During Fermentation of Raphanus sativus Roots with a Plantaricin-Producing Lactobacillus plantarum Starter.

The aim of the present study was to assess the transcription of the plnE/F, plnN, plnG, plnD and plnI genes during lactic acid fermentation of radish (Raphanus sativus) roots by Lactobacillus plantarum strain LQC 740 at 20 and 30 °C. At both temperatures, this strain dominated the fermentation process, as indicated by (GTG)5 analysis. A total of five pln genes were detected in the genome of this strain, namely plnE/F, plnN, plnG, plnD and plnI. Regarding plantaricin genes expression, no regulation was observed in the majority of the samples at both temperatures, therefore, the transcription of the pln genes was not affected by the experimental conditions, i.e. radish fermentation vs. growth in MRS broth. Although transcription of the pln genes was similar between the two conditions, bacteriocin activity was different. The maximum plantaricin activity was 87.5 AU/mL during radish fermentation and 700 AU/mL during growth in MRS broth. Thus, no apparent correlation between bacteriocin activity and transcription level of the five pln genes could be established.

Genetic Analysis of the Listeria Pathogenicity Island 1 of Listeria monocytogenes 1/2a and 4b Isolates.

The aim of the present study was to apply descriptive, phylogenetic, recombination, and selection analyses on alignments of the Listeria Pathogenicity Island 1 (LIPI-1) of 1/2a and 4b Listeria monocytogenes isolates of different origin in order to gain insights into the evolution of this virulence gene cluster. For that purpose, a total of 19 L. monocytogenes isolates (9 meat isolates, serotype 1/2a; 5 meat isolates, serotype 4b; 5 strawberry isolates, serotype 4b) that have been previously separated at strain level were subjected to sequencing of their LIPI-1. Descriptive analysis revealed extensive nucleotide diversity mostly in the intragenic regions. The actA gene of 1/2a and 4b meat isolates and the hly gene of the 4b strawberry isolates exhibited the higher diversity; limited diversity was observed in prfA and plcA genes of the 4b isolates and mpl gene of the 1/2a isolates. Phylogenetic analysis of the complete island resulted in two major clusters that were consistent with serotype assignment of the isolates. Moreover, effective discrimination between serotypes was obtained by plcA, plcB, mpl, actA and the intergenic regions plcA-prfA and plcA-hly. In all cases but plcB and plcA-prfA 4b isolates were also differentiated according to their source of isolation as well. Selection analysis revealed that the island consisted of randomly evolving DNA with the exception of prfA gene of 1/2a isolates and actA gene of 4b meat isolates for which purifying selection or population expansion was indicated. Finally, no statistically significant evidence for recombination has been observed.

Lactic acid bacteria population dynamics during spontaneous fermentation of radish (Raphanus sativus L.) roots in brine.

The aim of the present study was to assess the microecosystem development and the dynamics of the lactic acid bacteria population during spontaneous fermentation of radish (Raphanus sativus L.) roots in brine at 20 and 30 °C. In both temperatures, lactic acid bacteria prevailed the fermentation; as a result, the pH value was reduced to ca. 3.6 and total titrable acidity increased to ca. 0.4% lactic acid. Enterococci population increased and formed a secondary microbiota while pseudomonads, Enterobacteriaceae and yeasts/molds populations were below enumeration limit already before the middle of fermentation. Pediococcus pentosaceus dominated during the first days, followed by Lactobacillus plantarum that prevailed the fermentation until the end. Lactobacillus brevis was also detected during the final days of fermentation. A succession at sub-species level was revealed by the combination of RAPD-PCR and rep-PCR analyses. Glucose and fructose were the main carbohydrates detected in brine and were metabolized into lactic acid, acetic acid and ethanol.

Expression of Listeria monocytogenes key virulence genes during growth in liquid medium, on rocket and melon at 4, 10 and 30 °C.

The aim of the present study was to assess the expression of key virulence genes, during growth of a Listeria monocytogenes isolate in liquid medium, on melon and rocket at different temperatures and time. For that purpose, BHI broth, rocket and melon were inoculated at 7.0-7.5 log CFU mL(-1) or g(-1)and stored at 4, 10 and 30 °C. Sampling took place upon inoculation and after 0.5, 6 and 24 h of incubation. The RNA was stabilized and the expression of hly, plcA, plcB, sigB, inlA, inlB, inlC, inlJ, lmo2672 and lmo2470 was assessed by RT-qPCR. The results obtained were summarized into two observations; the first one referring to the interactive effect of incubation temperature and type of substrate and the second one to the effect of time on gene expression. Regarding the latter, nearly all genes were regulated upon inoculation and exhibited differential expression in the subsequent sampling times indicating the existence of additional regulatory mechanisms yet to be explored.

Effect of ripening stage on the development of the microbial community during spontaneous fermentation of green tomatoes.

BACKGROUND: Spontaneous fermentation of plant-derived material is mainly performed on a small scale, with the exception of fermented olives, cucumbers, sauerkraut and kimchi, which have met worldwide commercial significance. RESULTS: This study of spontaneous fermentation of green tomatoes at different stages of ripening revealed a significant effect on the growth kinetics of lactic acid bacteria and the final pH value. Leuconostoc mesenteroides dominated spontaneous fermentation when the initial pH value ranged from 3.8 to 4.8 whereas at higher pH values (4.9-5.4) it co-dominated with Leu. citreum and Lactobacillus casei. Application of RAPD-PCR and rep-PCR allowed differentiation at sub-species level, suggesting a microbial succession at that level accompanying the respective at species level. CONCLUSION: Ripening stage affected the development of the micro-ecosystem through the growth of lactic acid bacteria and concomitant pH value reduction; however, the outcome of the fermentation was only marginally different.

Food Safety and Management System Audits in Food Retail Chain Stores in Greece.

The present study aimed to assess the performance of food safety management systems in food retail stores via audits to reveal potential areas of improvement and to find out possible corrective actions to suggest to the top management. Two cycles of on-site audits took place in 106 stores to assess the requirements and hygiene conditions. After the first cycle of audits, improvements were suggested to the top management, and a second cycle of audits took place after a reasonable time. In the checklist, we recorded the temperatures of retail refrigerators and the scores from the inspection of hygiene and HACCP documentation. In the A' audit, the percentage of stores that had higher temperatures than the critical limits was equal to 51%, and those temperatures occurred in the refrigerators for salads, followed by the refrigerators for deli meat, yogurts and desserts. In the B' audit, only the refrigerators for salads exhibited percentages that were statistically significant lower (p-value < 0.05), and the stores were improved after the audit. High percentages of high-scoring stores were observed in the A' and B' audit in the inspection of HACCP documentation, although there was not a statistically significant improvement observed (p-value > 0.05). In the hygiene inspection, statistically significant improvement with 95% confidence appeared for "Refrigerator's products appearance", "Storage cleanliness", and "Grocery shelf cleanliness". The highest number of non-conformities without statistically significant improvement was found for "Checking temperatures of the receiving products" and "Labeling of fruit store products", with the percentages being lower than 15% in both of the audit cycles. Many employees of the stores did not check and record the temperatures of receiving products from suppliers. In addition, the storage of spoiled products beneath fresh products for selling in the same refrigerator is not a good practice. Greater efforts must be made by top management and employees to maintain and distribute food products in the best and safest possible hygiene conditions.

Quantifying Listeria monocytogenes prevalence and concentration in minced pork meat and estimating performance of three culture media from presence/absence microbiological testing using a deterministic and stochastic approach.

Listeria monocytogenes poses a serious threat to public health, and the majority of cases of human listeriosis are associated with contaminated food. Reliable microbiological testing is needed for effective pathogen control by food industry and competent authorities. The aims of this work were to estimate the prevalence and concentration of L. monocytogenes in minced pork meat by the application of a Bayesian modeling approach, and also to determine the performance of three culture media commonly used for detecting L. monocytogenes in foods from a deterministic and stochastic perspective. Samples (n = 100) collected from local markets were tested for L. monocytogenes using in parallel the PALCAM, ALOA and RAPID'L.mono selective media according to ISO 11290-1:1996 and 11290-2:1998 methods. Presence of the pathogen was confirmed by conducting biochemical and molecular tests. Independent experiments (n = 10) for model validation purposes were performed. Performance attributes were calculated from the presence-absence microbiological test results by combining the results obtained from the culture media and confirmative tests. Dirichlet distribution, the multivariate expression of a Beta distribution, was used to analyze the performance data from a stochastic perspective. No L. monocytogenes was enumerated by direct-plating (<10 CFU/g), though the pathogen was detected in 22% of the samples. L. monocytogenes concentration was estimated at 14-17 CFU/kg. Validation showed good agreement between observed and predicted prevalence (error = -2.17%). The results showed that all media were best at ruling in L. monocytogenes presence than ruling it out. Sensitivity and specificity varied depending on the culture-dependent method. None of the culture media was perfect in detecting L. monocytogenes in minced pork meat alone. The use of at least two culture media in parallel enhanced the efficiency of L. monocytogenes detection. Bayesian modeling may reduce the time needed to draw conclusions regarding L. monocytogenes presence and the uncertainty of the results obtained. Furthermore, the problem of observing zero counts may be overcome by applying Bayesian analysis, making the determination of a test performance feasible.

Bayesian inference for quantifying Listeria monocytogenes prevalence and concentration in minced pork meat from presence/absence microbiological testing.

The purpose of this work was to estimate the prevalence and concentration of Listeria monocytogenes in minced pork meat by the application of a Bayesian modeling approach. Samples (n = 100) collected from local markets were tested for L. monocytogenes using in parallel the PALCAM, ALOA and RAPID'L.mono selective media. Presence of the pathogen was confirmed through biochemical and molecular tests. Independent experiments (n = 10) for validation purposes were performed. No L. monocytogenes was enumerated by direct-plating (<10 CFU/g), though the pathogen was detected in 22% of the samples. Sensitivity and specificity varied depending on the culture method. L. monocytogenes concentration was estimated at 14-17 CFU/kg. Validation showed good agreement between observed and predicted prevalence (error = -2.17%). The use of at least two culture media in parallel enhanced the efficiency of L. monocytogenes detection. Bayesian modeling may reduce the time needed to draw conclusions regarding L. monocytogenes presence and the uncertainty of the results obtained.

Labelling Assessment of Greek "Quality Label" Prepacked Cheeses as the Basis for a Branded Food Composition Database.

A labelling assessment study of Greek prepacked "quality label" cheeses was conducted with a view to provide an overview of the whole category. In total, 158 prepacked products belonging to 19 "quality label" cheeses were identified in the Greek market. Among them, Feta had the highest share followed by Kasseri, Graviera Kritis, Kefalograviera and Ladotyri Mitilinis with 81, 16, 15, 11 and 9 products found in the market, respectively. For the rest of the 14 cheeses, the share was limited, ranging from 1 to 4. All labelling indications, nutritional information, claims and other labelling data were recorded and analysed in relation to their compliance against European food law requirements. The results of the analysis showed that for only 6 of the 19 cheeses, all products fully complied with EU labelling legislation. Among the 14 mandatory labelling requirements, the lowest overall compliance was observed for allergens declaration (65%). The analysis of the nutritional data showed a remarkable variability between cheeses and products. Differences in the nutritional characteristics were more pronounced among soft, semi-hard, hard and whey cheese. The above data were entered into an archival database. Application of global harmonisation and standardisation guidelines and tools lead to the initialisation of a branded food composition database (BFCD), conceptualising a specialised database for "quality label" foods.

Microbial Ecology of Artisanal Feta and Kefalograviera Cheeses, Part I: Bacterial Community and Its Functional Characteristics with Focus on Lactic Acid Bacteria as Determined by Culture-Dependent Methods and Phenotype Microarrays.

Artisanal cheesemaking is still performed using practices and conditions derived from tradition. Feta and Kefalograviera cheeses are very popular in Greece and have met worldwide commercial success. However, there is a lack of knowledge regarding their lactic acid microecosystem composition and species dynamics during ripening. Thus, the aim of the present study was to assess the microecosystem as well as the autochthonous lactic acid microbiota during the ripening of artisanal Feta and Kefalograviera cheeses. For that purpose, raw sheep's milk intended for cheesemaking, as well as Feta and Kefalograviera cheeses during early and late ripening were analyzed, and the lactic acid microbiota was identified using the classical phenotypic approach, clustering with PCR-RAPD and identification with sequencing of the 16S-rRNA gene, as well as with the Biolog GEN III microplates. In addition, the functional properties of the bacterial community were evaluated using the Biolog EcoPlates, which consists of 31 different carbon sources. In general, concordance between the techniques used was achieved. The most frequently isolated species from raw sheep's milk were Enteroroccus faecium, Lactiplantibacillus plantarum and Pediococcus pentosaceus. The microecosystem of Feta cheese in the early ripening stage was dominated by Lp. plantarum and E. faecium, whereas, in late ripening, the microecosystem was dominated by Weissella paramesenteroides. The microecosystem of Kefalograviera cheese in the early ripening stage was dominated by Levilactobacillus brevis and E. faecium, and in late ripening by W. paramesenteroides and E. faecium. Finally, Carbohydrates was the main carbon source category that metabolized by all microbial communities, but the extent of their utilization was varied. Kefalograviera samples, especially at early ripening, demonstrated higher metabolic activity compared to Feta cheese. However, dominating species within microbial communities of the cheese samples were not significantly different.

Microbial Ecology of Sheep Milk, Artisanal Feta, and Kefalograviera Cheeses. Part II: Technological, Safety, and Probiotic Attributes of Lactic Acid Bacteria Isolates.

The aim of the present study was to examine 189 LAB strains belonging to the species Enterococcus faecium, E. faecalis, Lactococcus lactis, Pediococcus pentosaceus, Leuconostoc mesenteroides, Lactiplantibacillus pentosus, Latilactobacillus curvatus, Lp. plantarum, Levilactobacillus brevis, and Weissella paramesenteroides isolated form sheep milk, Feta and Kefalograviera cheeses at different ripening stages, for their technological compatibility with dairy products manufacturing, their activities that may compromise safety of the dairy products as well as their capacity to survive in the human gastrointestinal tract. For that purpose, milk acidification and coagulation capacity, caseinolytic, lipolytic, hemolytic, gelatinolytic, and bile salt hydrolase activity, production of exopolysaccharides, antimicrobial compounds, and biogenic amines, as well as acid and bile salt tolerance and antibiotic susceptibility were examined. The faster acidifying strains were Lc. lactis DRD 2658 and P. pentosaceus DRD 2657 that reduced the pH value of skim milk, within 6 h to 5.97 and 5.92, respectively. Strains able to perform weak caseinolysis were detected in all species assessed. On the contrary, lipolytic activity, production of exopolysaccharides, amino acid decarboxylation, hemolytic, gelatinase, and bile salt hydrolase activity were not detected. Variable susceptibility to the antibiotics examined was detected among LAB strains. However, in the majority of the cases, resistance was evident. None of the strains assessed, managed to survive to exposure at pH value 1. On the contrary, 25.9 and 88.9% of the strains survived after exposure at pH values 2 and 3, respectively; the reduction of the population was larger in the first case. The strains survived well after exposure to bile salts. The strain-dependent character of the properties examined was verified. Many strains, belonging to different species, have presented very interesting properties; however, further examination is needed before their potential use as starter or adjunct cultures.

Development of a model describing the effect of temperature, water activity and (gel) structure on growth and ochratoxin A production by Aspergillus carbonarius in vitro and evaluation in food matrices of different viscosity.

The present study aimed: (i) to develop models for the combined effect of water activity (0.99, 0.94 and 0.90), microstructure expressed as 0, 5, 10 and 20% w/v gelatin, and temperature (15, 20 and 25 °C), on growth and OTA production rates by Aspergillus carbonarius; and (ii) to evaluate the performance of the developed models on food matrices (jelly, custard and marmalade) of different viscosity at pH 5.5. The square root of biomass increase rate (fungal growth rate) and OTA production rate were determined by the Baranyi model and were further modeled as a function of temperature, gelatin concentration and a(w) by applying polynomial models. Time for visible growth and the upper asymptote of the OTA production curve were also determined by the Baranyi model. Increase in gelatin concentration resulted in a significant delay in all parameters describing fungal growth and OTA production rates, at all temperatures and a(w). The effect of microstructure on fungal growth and OTA production rates was less evident at stress conditions of a(w) and temperature. Detection time for visible fungal growth was markedly influenced by a(w) and temperature. Coefficients of determination were 0.899 and 0.887 for the models predicting the square root (√µ(max)) of growth and OTA production rate, respectively. Predictions of growth rate agreed well with the recorded data of custard and marmalade, while observations of OTA production rate indicated low agreement with model predictions, in all food matrices except for marmalade. The present findings may provide a basis for reliable assessment of the risk of fungal growth and OTA production in foods of different structural and rheological properties.

Optimisation of octadecyl (C18) sorbent amount in QuEChERS analytical method for the accurate organophosphorus pesticide residues determination in low-fatty baby foods with response surface methodology.

Three low-fatty baby food matrices were fortified with 0.01-0.2mg/kg of phorate, diazinon, chlorpyrifos and methidathion. A "quick, easy, cheap, effective, rugged and safe" - like method (QuEChERS) was used. Quantities of octadecyl (C18) sorbent differed with fortification level and matrix fat, based on central composite experimental design. Quantification was performed by Nitrogen-Phosphorus Detector gas chromatography, using matrix-matched standards. The highest (p<0.05) recoveries were observed for methidathion, the lowest fortification levels for a specific C18 amount and the lowest C18 amounts. In meals containing vegetables (1.9% fat) and lamb (3.0% fat), 180-210mg C18 gave recoveries from 67.0% to 105.0% and absence of co-extracts. Yogurt dessert (4.5% fat) required 200-230mg C18 for similar results. Recoveries could also be predicted with <20% error by a polynomial model. The results suggest that modified QuEChERS could be effectively used in the low-fatty baby meals residue analysis.

Dietary Intake Assessment of Pre-Packed Graviera Cheese in Greece and Nutritional Characterization Using the Nutri-Score Front of Pack Label Scheme.

Gravieras are 'gruyere' type hard cheeses with a variety of different products and the second highest consumption in Greece. In this study, we present a dietary intake assessment and a nutritional characterization of pre-packed graviera products sold in the Greek market using Nutri-Score Front of Pack Label (FoPL). The nutrient contents of 92 pre-packed graviera products were combined with daily individual consumption data extracted from the Hellenic National Nutrition Health Survey (n = 93), attempting to evaluate the contribution of graviera's consumption to the Greek diet. The analysis of nutrients' intake as a Reference Intake (RI) percentage ranked saturated fat first on the nutrients' intake list, with RI percentage ranging from 36.1 to 109.2% for the 95th percentile of consumption. The respective % RI for energy, total fat, carbohydrates, sugars, proteins and salt ranged from 12.7-20.7%, 21.6-50.4%, 0-3.1%, 0-6.1%, 37-57.1% and 6.3-42%. Nutri-Score classified 1% of the products to C-light orange class, 62% to D-orange and 37% to E-dark orange, while no products were classified to A-dark green or B-green classes. The comparison between the Nutri-Score classification and the nutrients' intake assessment, also separately conducted within the classes, showed a higher salt intake after the consumption of products classified as D-orange and E-dark orange.

Εvaluation of oxygen availability on growth and inter-strain interactions of L. monocytogenes in/on liquid, semi-solid and solid laboratory media.

The coexistence and interactions among Listeria monocytogenes strains in combination with the structural characteristics of foods, may influence their growth capacity and thus, the final levels at the time of consumption. In the present study, we aimed to evaluate the effect of oxygen availability in combination with substrate micro-structure on growth and inter-strain interactions of L. monocytogenes. L. monocytogenes strains, selected for resistance to different antibiotics (to enable distinct enumeration), belonging to serotypes 4b (C5, ScottA), 1/2a (6179) and 1/2b (PL25) and were inoculated in liquid (Tryptic Soy Broth supplemented with Yeast Extract - TSB-YE) and solid (TSB-YE supplemented with 0.6% and 1.2% agar) media (2-3 log CFU/mL, g or cm2), single or as two-strain cultures (1:1 strain-ratio). Aerobic conditions (A) were achieved with constant shaking or surface inoculation for liquid and solid media respectively, while static incubation or pour plated media corresponded to hypoxic environment (H). Anoxic conditions (An) were attained by adding 0.1% w/v sodium thioglycolate and paraffin overlay (for solid media). Growth was assessed during storage at 7 °C (n = 3 × 2). Inter-strain interactions were manifested by the difference in the final population between singly and co-cultured strains. Τhe extent of suppression increased with reduction in agar concentration, while the impact of oxygen availability was dependent on strain combination. During co-culture, in liquid and solid media, 6179 was suppressed by C5 by 4.0 (in TSB-YE under H) to 1.8 log units (in solid medium under An), compared to the single culture, which attained population of ca. 9.4 log CFU/mL or g. The growth of 6179 was also inhibited by ScottA by 2.7 and 1.9 log units, in liquid culture under H and An, respectively. Interestingly, in liquid medium under A, H and An, ScottA was suppressed by C5, by 3.3, 2.4 and 2.3 log units, respectively, while in solid media, growth inhibition was less pronounced. Investigating growth interactions in different environments could assist in explaining the dominance of L. monocytogenes certain serotypes.

High-quality draft genome sequence data of six Lactiplantibacillus plantarum subsp. argentoratensis strains isolated from various Greek wheat sourdoughs.

Lactiplantibacillus plantarum is a species found in a wide range of foods and other commodities. It can be used as starter or adjunct culture in fermented foods. Herein the annotated high-quality draft genome (scaffolds) of six L. plantarum subsp. argentoratensis strains (LQC 2320, LQC 2422, LQC 2441, LQC 2485, LQC 2516 and LQC 2520) isolated from various Greek wheat sourdoughs is presented. Raw sequence reads were quality checked, assembled into larger contiguous sequences and scaffolds were annotated. The total size of the genomes ranged from 3.13 Mb to 3.49 Mb and the GC content from 45.02% to 45.13%. The total number of coding and non-coding genes were between 3268 and 3723 (3091 to 3492 protein-coding genes, 62 to 107 repeat-region, 54 to 59 tRNAs and 2 to 5 rRNAs, 20 to 30 crispr-repeats, 17 to 26 crispr-spacers and 2 to 4 crispr-arrays). The Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession numbers JAEQMR000000000, JAEQMQ000000000, JAEQMP000000000, JAEQMO000000000, JAEQMN000000000 and JAEQMM000000000. The version described in this paper is version JAEQMR010000000, JAEQMQ010000000, JAEQMP010000000, JAEQMO010000000, JAEQMN010000000 and JAEQMM010000000. Raw sequence reads have been submitted in the Sequence Read Archive (SRA) under the BioProject accession number PRJNA689714 (BioSample accession numbers SAMN17215143, SAMN17215144, SAMN17215145, SAMN17215146, SAMN17215147 and SAMN17215148 and SRA accession numbers SRR13357463, SRR13357464, SRR13357465, SRR13357466, SRR13357467, SRR13357468).

Technological and Safety Attributes of Lactic Acid Bacteria and Yeasts Isolated from Spontaneously Fermented Greek Wheat Sourdoughs.

The aim of the present study was to assess the technological and safety potential of 207 lactic acid bacteria (LAB) and 195 yeast strains isolated from spontaneously fermented Greek wheat sourdoughs. More accurately, the amylolytic, proteolytic, lipolytic, phytase and amino acid decarboxylase activities, along with the production of exopolysaccharides and antimicrobial compounds by the LAB and yeast isolates, were assessed. A well diffusion assay revealed seven proteolytic LAB and eight yeast strains; hydrolysis of tributyrin was evident only in 11 LAB strains. A further Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) indicated partial hydrolysis of gluten. Lipolysis kinetics over 21 days was applied, exhibiting that lipolytic activity ranged from 6.25 to 65.50 AU/mL. Thirteen LAB inhibited Penicillium olsonii and Aspergillus niger growth and 12 yeast strains inhibited Pe. chrysogenum growth. Twenty-one Lactiplantibacillus plantarum strains exhibited inhibitory activity against Listeria monocytogenes, as well as several sourdough-associated isolates. The structural gene encoding plantaricin 423 was detected in 19 Lcb. plantarum strains, while the structural genes encoding plantaricins NC8, PlnE/F, PlnJ/K, and S were detected in two Lcb. plantarum strains. None of the microbial strains tested exhibited exopolysaccharide (EPS) production, amino acid decarboxylase, amylolytic or phytase activity. The technological and safety potential of the Lcb. plantarum and Wickerhamomyces anomalus strains was highlighted, since some of them exhibited proteolytic, lipolytic, antibacterial and antimould activities.

Microbial Profile Antibacterial Properties and Chemical Composition of Raw Donkey Milk.

The human interest in donkey milk is growing due to its nutritional, functional properties and excellent microbiological quality according to published reports. However, more research needs to be conducted to assess the above variables from various breeds. In the present study, milk samples were collected from 17 Cypriot and six Arcadian healthy Greek donkeys. The microbiological quality, somatic cell counts (SCC), chemical composition analysis, and antimicrobial activity of the samples was assessed. In addition, clustering and identification of the bacterial composition was performed by RAPD-PCR and 16S rDNA sequencing, respectively. The good microbiological quality of the samples as estimated by the total aerobic mesophilic and psychrotrophic counts, which ranged from 2.18 to 2.71 log CFU/mL and from 1.48 to 2.37 log CFU/mL, respectively, was also verified. SCC were below 4.4 log CFU/mL. However, potential pathogenic species of Staphylococcus aureus, Bacillus cereus, and Clostridium spp. were enumerated in the milk of both breeds. The gross chemical composition showed mean values for fat, protein, and lactose from 0.82% to 1.24%, 1.22% to 1.87%, and 6.01% to 6.78%, respectively. All milk samples exhibited an antimicrobial activity against St. haemolyticus and Listeria monocytogenes, although quality control measures should be taken for health and safety prior to human consumption.

Nutritional Characteristics of Prepacked Feta PDO Cheese Products in Greece: Assessment of Dietary Intakes and Nutritional Profiles.

Feta cheese, a protected designation of origin (PDO) food, is one of the most important Mediterranean food products. Although it is the cheese with the highest consumption in Greece, the nutritional characteristics of products available in the market, as well as their contribution to the Greek diet, have not been evaluated in detail. In the present study, the basic nutritional content of 81 prepacked feta cheese products available in the Greek market were recorded based on their labels. This was combined with consumption data to provide an overall picture of feta cheese's contribution to the Greek diet. The nutrient contents per 100 g ranged as follows. Energy: 221-343 kcal, total fat: 20-29 g, saturated fat: 12.8-20.3 g, carbohydrates: 0-3.1 g, sugars: 0-3 g, proteins: 13.1-21.0 g and salt: 1.2-5.1 g. The median feta daily individual consumption was found to be 39 g, ranging from 20 g to 100 g (fifth and 95th percentiles, respectively). The nutritional intake analysis as a percentage of dietary reference intake (DRI) showed that saturated fat and salt are ranked on the top of the list, with intakes reaching 101.5% and 85% respectively. The products were also evaluated against five nutrient profile models and their potential use under statutory requirements and policy development are discussed.