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The rind acts as a protective barrier for internally-bacterial ripened cheeses. Unlike surface-inoculated smear cheeses, centripetal maturation is not assumed to occur in these cheeses. This research was aimed to evaluate the microbial diversity of the wooden shelves used for the ripening of Protected Denomination of Origin (PDO) Pecorino di Filiano and Protected Geographical Indication (PGI) Canestrato di Moliterno cheeses. The microorganisms associated with the rind of these cheeses were also investigated. Both wooden shelf surfaces and cheese rinds were sampled by brushing method to collect their biofilms. Wooden shelves showed levels of total mesophilic microorganisms (TMM) between 5.6 and 7.2 log CFU/cm2, while cheese rinds between 6.1 and 7.8 log CFU/cm2. The major dairy pathogens (Salmonella spp., Listeria monocytogenes , Escherichia coli , and Staphylococcus aureus) were never detected, while mesophilic and thermophilic bacteria dominated the surfaces of all wooden shelves and cheese rinds. LAB community was represented by Enterococcus spp., Leuconostoc spp., and Marinilactibacillus spp. Among yeasts, Debaryomyces spp., Candida spp., were identified, while Aspergillus spp., and Penicillium spp., dominated the community of filamentous fungi. MiSeq Illumina analysis identified 15 phyla, 13 classes, 28 orders, 54 families, and 56 genera among bacteria. Staphylococcus spp. was identified from all wooden surfaces, with a maximum abundance of 71 %. Brevibacterium , Corynebacterium and halophilic bacteria were detected in almost all samples. Regarding fungi, wooden shelves mainly hosted Aspergillus , Penicillium and Debaryomyces hansenii , while cheese rinds especially Penicillium and D. hansenii. Alpha diversity confirmed a strict correlation between the microbiota of wooden shelves and that of cheese rinds for the majority of factories. This study confirmed that the wooden shelves used for cheese ripening are microbiologically active and represent safe systems. Furthermore, the results of this work clarified the transfer flow between wooden shelves and PDO Pecorino di Filiano and PGI Canestrato di Moliterno cheese surfaces: smear-active microorganisms are mainly transferred from wooden shelves to cheese rind, which potentially contribute to the development of the final organoleptic characteristics; meanwhile, cheeses transfer LAB that are potentially involved in defining the safety aspects of the shelves. • Wooden planks hosted total mesophilic microorganisms (TMM) at 5.6–7.2 log CFU/cm2. • Cheese rinds TMM accounted to 6.1 and 7.8 log CFU/cm2. • LAB community of cheese rinds and wooden shelves mainly hosted Enterococcus. • Debaryomyces hansenii dominated yeast community of cheese rinds and wooden shelves. • Microbiota of cheese rinds indicated the occurrence of a centripetal maturation. [ABSTRACT FROM AUTHOR]

Abstract Previous investigations on pizza dough lactic acid bacteria (LAB) revealed that facultative heterofermentative species (FHS) were more represented than obligate heterofermentative species (OHS) within the Lactobacillus genus. Thus, the main hypothesis of this work was that facultative and obligate heterofermentative Lactobacillus species can impact differently the appreciation of baked pizza. The performances of different Lactobacillus , including L. sanfranciscensis , L. brevis and L. rossiae among OHS and L. plantarum , L. graminis and L. curvatus among FHS were tested in single or multiple combinations during pizza production. The values of pH, total titratable acidity and LAB levels indicated that the acidification process was almost comparable among trials. The fermentation quotient of FHS trials was above 4.0. All trials were dominated by the added LAB and for the trials with the multiple strain starter inoculums, the species found at the highest cell densities were L. sanfranciscensis , L. brevis and L. plantarum. Significant differences among pizzas were found for weight loss, colour, morphology and volatile organic compounds (VOCs). The last analysis revealed the presence of eight chemical classes with aldehydes, esters, alcohols and acids as major compounds and allowed the separation of the trials FHS and OHS. Sensory attributes were significantly different for judges and pizzas and the most relevant differences were found for crust colour, presence of bubbles, resistance to tearing, crispness and chewiness. The overall assessment reached the highest scores for the mixed culture of OHS and FHS together. Highlights • Facultative and obligate heterofermentative Lactobacillus grew similarly. • Pizza doughs were dominated by L. sanfranciscensis , L. brevis and L. plantarum. • Facultative heterofermentative species determined the highest fermentation quotient. • Chemical and physical analyses indicated differences among trials. • The best results were registered in the presence of the most complex mixed inoculums. [ABSTRACT FROM AUTHOR]

Almond production generates large amounts of by-products rich in polyphenols. In this study, almond skin was explored as a valuable food ingredient in bread making. To this purpose, almond skin was used to produce functional products modifying a traditional sourdough bread recipe. The doughs were prepared replacing semolina with powdered almond skin (PAS) at 5 and 10 % (w/w). Sourdough inoculum was started with a mix of lactic acid bacteria (LAB) and propagated in semolina until reaching pH 3.7. The pH of PAS added breads was higher than that of control (CTR) breads before and after fermentation. Plate counts showed a similar evolution of LAB and total mesophilic microorganisms, but members of Enterobacteriaceae and coliform were detectable in PAS doughs. Illumina data clearly showed a dominance of lactobacilli in all trials, but PAS doughs displayed the presence of Bacillus. The final bread characteristics were influenced by PAS and its addition percentage; in particular, crust and crumb colour resulted darker, the alveolation decreased and, regarding sensory attributes, odour intensity increased, while bread odour diminished. In presence of PAS, bread emissions were characterized by lower percentages of alcohols and aromatic hydrocarbons and higher percentages of the other volatile compound classes, especially terpenoids like β-pinene, β-myrcene and limonene than CTR trial. After in vitro simulated digestion, the final release of phytochemicals from 10 % PAS bread was almost 100 %. Thus, PAS determined an increase of the antioxidant capacity of the breads. Phytochemicals released from digested PAS-fortified bread can provide antioxidant protection in a complex biological environment such as human intestinal-like cells. Besides the positive functional properties of PAS, this work also evidenced the hygienic issues of almond skin and, in order to avoid potential risks for the human health, highlighted the need to preserve its microbiological characteristics during storage for their reuse in bread production. • Powder almond skin (PAS) did not affect the growth of starter lactic acid bacteria. • PAS slightly slowed down the acidification process. • Lactobacilli were absent in PAS, but detected in all doughs at relative abundances. • PAS phytochemicals provided antioxidant protection to human intestinal-like cells. [ABSTRACT FROM AUTHOR]

The “Spiritu re fascitrari” (SRF) is a typical Sicilian distillate obtained from the by-products of traditional process of honey production. Although some alcoholic fermentation of honey based products have been described, the present research represents the first investigation on the yeast ecology and the physico-chemical characteristics of honey by-products subjected to an alcoholic fermentation followed by distillation. All samples collected during manufacturing process were analysed for the count of total, osmophilic and osmotolerant yeasts. The honeycombs and equipment surfaces showed the presence of yeasts that was 1.7 and 1.1 Log (CFU/mL), respectively. After enrichment, yeast populations increased and a significant increase of yeasts was registered during the alcoholic fermentation (AF), reaching loads higher than 7 Log CFU/mL after day 6. A total of 2816 colonies of yeasts were isolated from the count plates and the following species were genetically identified: Lachancea fermentati , Pichia anomala , Pichia kudriavzevii , Saccharomyces cerevisiae , Wickerhamomyces anomalus , Zygosaccharomyces bailii and Zygosaccharomyces rouxii . During the spontaneous AF process, the species S. cerevisiae , Z. bailii and Z. rouxii were mainly isolated and the feed conversion ratio of sugars into ethanol was about 53%; high contents of acetic acid and glycerol were also found. The highest concentrations of volatile organic compounds (VOCs) were registered for esters, alcohols and aldehydes (346.55, 331.041 and 13.65 μg/L, respectively). Many VOCs identified as “specific floral markers” such as nonanal and 1-hexanol, 1-octanal and linalool oxide were found. Although more studies are needed, our results suggested that the S. cerevisiae strains isolated in this study must be evaluated in situ for their potential to act as starters for the continuous production of SRF. This because these strains are expected to drive the fermentation process reducing the risk of off-odour and off-flavour formation. [ABSTRACT FROM AUTHOR]

Forty enterococci isolated along the production chains of three traditional cheeses (PDO Pecorino Siciliano, PDO Vastedda della Valle del Belìce, and Caciocavallo Palermitano) made in Sicily (southern Italy) were studied for the assessment of their antibiotic resistance and virulence by a combined phenotypic/genotypic approach. A total of 31 Enterococcus displayed resistance to at least one or more of the antimicrobials tested. The strains exhibited high percentages of resistance to erythromycin (52.5%), ciprofloxacin (35.0%), quinupristin–dalfopristin (20.0%), tetracycline (17.5%), and high-level streptomycin (5.0%). The presence of tet (M), cat (pC221), and aad E genes for resistance to tetracycline, chloramphenicol, and streptomycin, respectively, was registered in all strains with resistance phenotype. The erm (B) gene was not detected in any erythromycin-resistant strain. The Enterococcus strains were further tested by PCR for the presence of virulence genes, namely, gel E, asa1 , efaA , ace , and esp . Twenty strains were positive for all virulence genes tested. Among the enterococci isolated from final cheeses, three strains (representing 33.3% of total cheese strains) were sensible to all antimicrobials tested and did not carry any virulence factor. Although this study confirmed that the majority of dairy enterococci are vectors for the dissemination of antimicrobial resistance and virulence genes, only two strains showed a high resistance to aminoglycosides, commonly administered to combat enterococci responsible for human infections. Furthermore, the presence of the strains E. casseliflavus FMAC163, E. durans FMAC134B, and E. faecium PON94 without risk determinants, found at dominating levels over the Enterococcus populations in the processed products, stimulates further investigations for their future applications in cheese making. All strains devoid of the undesired traits were isolated from stretched cheeses. Thus, this cheese typology represents an interesting environment to deepen the studies on the risk/benefit role of enterococci in fermented foods for their qualified presumption of safety (QPS) assessment. [ABSTRACT FROM AUTHOR]

The demand for unique and exclusive food products and beverages is constantly on the increase. One of the products that mostly evolved to encounter market dynamics in the last decade is craft beer. For a long time, craft breweries have included fruit in beer production to enrich flavour and aroma profile of different beer styles. In this study, for the first time, the use of Saccharomyces and non- Saccharomyces yeast strains isolated from high-sugar matrices (manna and fermented honey by-products) were investigated to diversify fruit craft beer production, in order to improve the fermentation process and highlight the complexity of aroma profiles generated during alcoholic fermentation. Two yeast strains, Hanseniaspora uvarum YGA34 and Saccharomyces cerevisiae MN113, were tested as co-starters and starters for their beer production capacity. Commercial yeast strain US-05 was used as control. Loquat juice was added at the end of primary alcoholic fermentation in all trials. Interestingly, S. cerevisiae MN113 consumed sugars faster than control strain S. cerevisiae US-05, including maltose, even in the case of sequential inoculation. This strain showed an excellent ability to consume rapidly sugars present. All strains showed their concentrations ranged between 5 and 8 Log cycles during fermentation. The absence of off-odours and the improvement of aromatic perception were observed in experimental trials involving the use of S. cerevisiae MN113 as a monoculture and in sequential combination with H. uvarum YGA34. Esters and alcohols were the most abundant compounds emitted from the beers. The beers produced with sequential inoculation of H. uvarum YGA34 and S. cerevisiae MN113 or US-05 are characterised by a higher ester and lower alcohol concentration. These two unconventional yeast strains from high sugar matrices showed great technological properties, representing promising co-starters and starter during craft fruit beer production. • After 3 days, S. cerevisiae MN113 showed the highest value of fermentation rate. • S. cerevisiae MN113 consumed sugars faster than control strain. • Beers fermented with wild yeasts showed improvement in aroma perception. • Sequential inocula are characterised by a higher final concentration of esters. • The highest sensory scores were obtained in beers fermented with wild strains. [ABSTRACT FROM AUTHOR]

Abstract: Twelve lactic acid bacteria (LAB), previously selected in vitro (Gaglio et al., 2014), were evaluated in situ for their potential to act as starter cultures for the continuous four-season production of Vastedda-like cheese, made with raw ewes' milk. The strains belonged to Lactobacillus delbrueckii, Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides subsp. mesenteroides and Streptococcus thermophilus. LAB were first inoculated in multiple-strain combinations on the basis of their optimal growth temperatures in three process conditions which differed for milk treatment and medium for strain development: process 1, growth of strains in the optimal synthetic media and pasteurised milk; process 2, growth of strains in whey based medium (WBM) and pasteurised milk; and process 3, growth of strains in WBM and raw milk. The strains that acidified the curds in short time, as shown by a pH drop, were all mesophilic and were then tested in a single inoculum through process 3. Randomly amplified polymorphic DNA (RAPD)-PCR analysis applied to the colonies isolated from the highest dilutions of samples confirmed the dominance of the added strains after curd acidification, stretching and storage. After 15days of refrigerated storage, the decrease in pH values showed an activity of the mesophilic strains at low temperatures, but only Lc. lactis subsp. cremoris PON153, Ln. mesenteroides subsp. mesenteroides PON259 and PON559 increased their number during the 15days at 7°C. A sensory evaluation indicated that the cheeses obtained by applying protocol 3 and by inoculation with lactococci are the most similar to the protected denomination of origin (PDO) cheese and received the best scores by the judges. Thus, the experimental cheeses obtained with raw milk and inoculated with single and multiple combinations of lactococci were subjected to the analysis of the volatile organic compounds (VOCs) carried out by a headspace solid phase microextraction (SPME) technique coupled with gas chromatography with mass spectrometric detection (GC/MS). The dominance of lactococci over thermophilic LAB of raw milk was verified during summer production and, based on the combination of VOC profiles and sensory evaluation of the final cheeses, the multi-strain Lactococcus culture resulted in the most suitable starter preparation for the full-year production of Vastedda-like cheese. [Copyright &y& Elsevier]

Abstract: The aim of the present work was to investigate the microbiological, chemical, and sensory characteristics of red wine subjected to post-fermentation maceration that was extended to 90days. For this purpose, the ‘Aglianico di Taurasi’ grape was used as a case study. The total yeast concentration increased until day 40 of maceration and decreased thereafter, whereas the concentration of lactic acid bacteria slightly increased. Dekkera/Brettanomyces spp. and acetic acid bacteria were not detected. The yeast community was composed of Saccharomyces cerevisiae, Zygosaccharomyces bisporus, Metschnikowia pulcherrima, Hanseniaspora guilliermondii, Hanseniaspora uvarum, Pichia guilliermondii, Aureobasidium pullulans and Debaryomyces carsonii. Nine S. cerevisiae strains were detected at high levels at different times of maceration. The results of all the conventional chemical analyses of the wines were in agreement with the regulations of commercial production and, interestingly, the changes in terms of concentration demonstrated the presence of yeast and LAB populations that were not only alive but also in a metabolically active state until day 90 of maceration. The alcohol and glycerol contents slightly increased until day 90. The concentrations of malic acid decreased, whereas those of lactic acid slightly increased throughout the maceration process. Furthermore, different durations of maceration resulted in significant differences in the total polyphenol content, which was higher at 40–50days. The main phenolic compounds were benzoic and cinnamic acids and catechins. Interestingly, the highest ratio between (+)-catechin and (−)-epicatechin was found on day 40. In addition, the highest antioxidant activity was observed between days 40 and 50. The concentration of volatile organic compounds, which were mainly represented by alcohols, increased until the end of the maceration process. Sensory analysis revealed that samples that were subjected to maceration for a long period of time showed the highest odour and taste complexity and no off-odours and/or off-flavours were detected. These data confirmed that extending post-fermentation maceration to 90days has no negative impact on the microbiological, chemical and sensory composition of wines, but affects the polyphenol content and potential health benefits of the resulting wine. [Copyright &y& Elsevier]

Catarratto is one of the most common non-aromatic white grape varieties cultivated in Sicily (Southern Italy). In order to improve the aromatic expression of Catarratto wines a trial was undertaken to investigate the effect of yeast strain, nutrition and reduced glutathione. Variables included two Saccharomyces cerevisiae strains, an oenological strain (GR1) and one isolated from honey by-products (SPF52), three different nutrition regimes (Stimula Sauvignon Blanc™ (SS), Stimula Chardonnay™ (SC) and classic nutrition practice), and a specific inactivated yeast rich in reduced glutathione to prevent oxidative processes [Glutastar™ (GIY)] ensuing in ten treatments (T1-T10). Microbiological and chemical parameters demonstrated the aptitude of strain SPF52 to successfully conduct alcoholic fermentation. During fermentation, the Saccharomyces yeast populations ranged from 7 to 8 logarithmic CFU/mL. All wines had a final ethanol content ranging between 12.91 and 13.85% (v /v). The dominance of the two starter strains over native yeast populations was higher than 97% as estimated by interdelta analysis. The addition of nutrients SS or SC increased the aromatic complexity of the wines as reflected by volatile organic compounds (VOCs) composition and sensory profiles. In particular, 32 VOCs were identified; alcohols (62.46–81.1%), thiols (0.27–0.87%), ethers (0.09–0.16%), aldehydes (0–1.21%), ketones (0–2.28%), carboxylic acids (4.21–12.32%), esters (0–10.85%), lactones (0.9–1.49%) and other compounds (0.77–6.9%). Sensory analysis demonstrated a significant impact on wine aroma in relation to yeast starter strain used, the type of nutrition (SS, SC or classic nutrition) and the presence/absence of GIY. The wines produced with GR1 yeast strain and SS (T2), SPF52 with SC (T9) both in presence of GIY showed higher overall quality. Trials T2 and T9 showed the highest scores for 13 and 18 attributes, respectively. The different nutrition, addition of GIY and the yeast starter strains diversified and enhanced sensory expression of Catarratto wines. • The strain SPF52 of S. cerevisiae was proven suitable for wine production. • The dominance of the two starter over native yeast populations was higher than 97%. • VOCs were mainly represented by 3-methyl-1-butanol and phenylethyl alcohol. • Sensory scores varied greatly among the trials carried out with different nutrients. • Glutastar™ was useful to generate the highest aromatic intensity. [ABSTRACT FROM AUTHOR]

Abstract: The survival of eight undesired (spoilage/pathogenic) food related bacteria (Citrobacter freundii PSS60, Enterobacter spp. PSS11, Escherichia coli PSS2, Klebsiella oxytoca PSS82, Serratia grimesii PSS72, Pseudomonas putida PSS21, Stenotrophomonas maltophilia PSS52 and Listeria monocytogenes ATCC 19114T) was investigated in mineral nutrient solution (MNS) during the crop cycle of radishes (Raphanus sativus L.) cultivated in hydroponics in a greenhouse. MNSs were microbiologically analyzed weekly by plate count. The evolution of the pure cultures was also evaluated in sterile MNS in test tubes. The inoculated trials contained an initial total mesophilic count (TMC) ranging between 6.69 and 7.78Log CFU/mL, while non-sterile and sterile control trials showed levels of 4.39 and 0.97Log CFU/mL, respectively. In general, all inoculated trials showed similar levels of TMC in MNS during the experimentation, even though the levels of the inoculated bacteria decreased. The presence of the inoculums was ascertained by randomly amplified polymorphic DNA (RAPD) analysis applied on the isolates collected at 7-day intervals. At harvest, MNSs were also analyzed by denaturing gradient gel electrophoresis (DGGE). The last analysis, except P. putida PSS21 in the corresponding trial, did not detect the other bacteria, but confirmed that pseudomonads were present in un-inoculated MNSs. Despite the high counts detected (6.44 and 7.24CFU/g), only C. freundii PSS60, Enterobacter spp. PSS11 and K. oxytoca PSS82 were detected in radishes in a living form, suggesting their internalization. [Copyright &y& Elsevier]

This work was carried out to elaborate selenium (Se) bio-enriched fermented Mediterranean fruit juices. To this purpose, pomegranate and table red grape juices were added with sodium selenite (Na 2 SeO 3) and fermented by Levilactobacillus brevis CRL 2051 and Fructobacillus tropaeoli CRL 2034 individually or combined. To better evaluate the effect of selenite addition and starter strain inoculums on the total bacterial community of the fruit juices, fermentation trials were performed with raw and pasteurized fruit juices. No statistical significant differences were observed for total mesophilic microorganisms (TMM) and rod-shaped lactic acid bacteria (LAB) levels among raw and pasteurized juices inoculated with the starter strains, while significant differences between those juices with and without selenite were registered. LAB cocci, Pseudomonadaceae and yeasts were detected only for the raw juice preparations. The dominance of L. brevis CRL 2051 and F. tropaeoli CRL 2034 was confirmed by randomly amplified polymorphic DNA (RAPD)-PCR analysis. After fermentation, pH dropped for all inoculated trials and control raw juices. The soluble solid content (SSC) levels of the raw juices were higher than the corresponding pasteurized trials. The thermal treatment affected consistently yellowness of grape juice trials and redness of pomegranate juices. No microbial Se accumulation was registered for pomegranate juices, while F. tropaeoli CRL 2034 accumulated the highest amount of Se (65.5 μg/L) in the grape juice. For this reason, only trials carried out with raw grape juices were investigated by metagenomics analysis by Illumina MiSeq technology. Non-inoculated grape juices were massively fermented by acetic acid bacteria while Fructobacillus and Lactobacillus (previous genus name of Levilactobacillus) represented the highest operational taxonomy units (OTUs) relative abundance % of the trials inoculated with the starter strains as confirmed by this technique. • Levilactobacillus brevis and Fructobacillus tropaeoli fermented red fruit juices. • The strongest pH drop was determined by L. brevis CRL 2051. • F. tropaeoli CRL 2034 accumulated the highest amount of Se in grape juice. • Non-inoculated grape juices were massively fermented by acetic acid bacteria. • 480 mL of fermented grape juice provide half of the Se recommended dietary allowance. [ABSTRACT FROM AUTHOR]

A phenotypic and genotypic characterization of 84 Oenococcus oeni isolates from Italian wines of different oenological areas was carried out. Numerical analysis of fatty acid profiles grouped the isolates into two clusters at low level of similarity (63%), the minor cluster containing seven isolates besides the type and the reference strains. Forthy-eight O. oeni isolates, representative of the two clusters, showed no differences in their metabolic properties (heterolactic fermentation pattern, citrate degradation capability and formation of some secondary metabolites). Moreover, the analysis of species-specific randomly amplified polymorphic DNA and 16S–23S rDNA intergenic spacer region polymorphism as well as the sequence-specific separation of V3 region from 16S rDNA by denaturing gradient gel electrophoresis demonstrated a substantial homogeneity among the isolates. On the basis of ApaI Pulsed Field Gel Electrophoresis (PFGE) restriction patterns, the 84 isolates were grouped into five different clusters at 70% similarity, but no correlation with the phenotypic groups could be demonstrated. However, by combining phenotypic and genotypic data, the 84 O. oeni isolates grouped into eight phenotypic–genotypic combined profiles and a relationship between the origin of the isolates and their combined profile became evident, so that a sort of strain specificity can be envisaged for each wine-producing area. [Copyright &y& Elsevier]

In the present work the microbial dynamics in wheat kernels were evaluated over time. The main aim of this research was to study the resistance of lactic acid bacteria (LAB) and yeasts associated to unprocessed cereals used for bread making during long term conservation. To this purpose four Triticum durum Desf. genotypes including two modern varieties (Claudio and Simeto) and two Sicilian wheat landraces (Russello and Timilia) were analysed by a combined culture-independent and -dependent microbiological approach after one, two or three years from cultivation and threshing. DNA based MiSeq Illumina technology was applied to reveal the entire bacterial composition of all semolina samples. The samples showed a different distribution of bacterial taxa per variety and time of storage. The groups mostly represented were Stenotrophomonas , Pseudomonas , Erwinia , Delftia and Sphingomonas genera, Enterobacteriaceae and Oxalobacteriaceae families, and Actinobacteria phylum. Among LAB, only Enterococcus genus was detected barely in a single sample (Simeto stored for one year) by the next generation sequencing, indicating that LAB remained unassigned or their abundances were below 0.1% or their DNAs were rendered inaccessible. Plate counts showed consistent differences in relation to genotypes and duration of storage, with the highest levels found for total mesophilic microorganisms detected up 6.8 Log CFU/g. Colonies of presumptive sourdough LAB were detected only in a few samples. Cocci constituted the major group of LAB in almost all samples. Following the enrichment procedure, almost all samples were characterised by the presence of acidifying microorganisms. All isolates collected before and after enrichment represented 28 different strains belonging to 10 species of Enterococcus , Lactobacillus and Pediococcus genera. The most resistant species during aging were Enterococcus faecium , Enterococcus durans , Lactobacillus brevis , Lactobacillus pentosus and Lactobacillus paracasei demonstrating that lactobacilli and enterococci are able to overcome the stressing conditions represented by cereal storage better than other LAB genera commonly found associated to cereals after harvest. Yeast community included mostly species with no interest in bread making. • Lactic acid bacteria levels varied for wheat genotype and storage duration. • Enterobacteria were among the major groups for all samples as revealed by Illumina. • Temporal distribution showed a reduction of LAB presence during aging of kernels. • Lactobacilli and enterococci are able to overcome the stressing conditions of aging. [ABSTRACT FROM AUTHOR]