The Lesvos sheep breed is an autochthonous Greek breed well adapted to the xerothermic conditions of Lesvos Island and is mainly exploited for milk production. In this study, 119 bacterial isolates from eight geographically well-spread samples of raw Lesvos breed sheep milk were identified. Based on rep-PCR genotypic profiling, 47 lactic acid bacteria (LAB) isolates were selected and evaluated for probiotic potential, with several among them exhibiting one or more probiotic traits. Notably, Limosilactobacillus fermentum 503 showed angiotensinconverting enzyme inhibitory (ACE-I), antimicrobial and gamma-aminobutyric acid (GABA) producing activities. Among Lacticaseibacillus casei/paracasei/rhamnosus isolates, strains 103 and 708 displayed ACE-I activity and adhered to collagen-coated plates, while strains 702 and 712 exhibited ACE-I, antimicrobial and bile salt hydrolase (BSH) activities. Streptococcus macedonicus 311 demonstrated ACE-I, antimicrobial and adhesion properties. Overall, raw milk from Lesvos breed sheep represents a rich and largely unexplored source of promising probiotic candidates for functional food development.

Donkey milk has gained increasing attention in recent years for its unique nutritional, medicinal, and cosmetic properties. This study employed a metataxonomic approach to investigate the microbiota of donkey milk samples collected from all farms operating in Greece during 2020-2021. Complementary chemical and culture-dependent microbiological analyses were performed alongside evaluation of milk fatty acid composition and antioxidant activity. Milk composition analyses showed no significant differences with published values, with variation observed only in fat content. Metataxonomic analysis identified the genera Acinetobacter, Enterococcus, Pseudomonas and Staphylococcus among the most abundant bacterial taxa, while Alternaria, Debaryomyces and Udeniomyces were the predominant yeast genera. Both classical microbiological and metataxonomic analysis confirmed the presence of lactic acid bacteria species. Several bacterial and fungal taxa correlated positively with donkey milk fatty acid content, while others negatively with milk total antioxidant capacity, thus affecting its composition and antioxidant potential.

The comprehensive analysis of microbial communities reveals the unique microbial identity of different olive varieties, paving the way for new strategies in their development and commercial exploitation. In this context, the present study aimed to explore the microbial diversity and functional characteristics of Tsounati variety olives from the Monemvasia region of Peloponnese, Greece, that were naturally fermented for three months. The bacterial and fungal microbiota of both olives and brines were fingerprinted throughout the fermentation through classical microbiological analysis combined with molecular techniques. Among the 148 isolated bacteria, 85 were lactic acid bacteria (LAB), and 63 belonged to the Enterobacteriaceae family, while the 178 fungal isolates comprised 136 yeasts and 42 non-yeast or yeast-like fungi. Metataxonomic analysis confirmed the dominance of the bacterial genera Lactiplantibacillus, Leuconostoc, along with the Enterobacteriaceae family, and it revealed the presence of Coleofasciculaceae cyanobacteria mostly in olives. The dominant fungal genera were yeasts, namely Saccharomyces, Nakazawaea, and Cyberlindnera. Using the Folin–Ciocalteu assay, the average total polyphenol content of Tsounati fermented olive samples was 761.80 ± 128.87 mg gallic acid equivalents kg−1 after 90 days of fermentation. The concentrations of the triterpenic, maslinic, and oleanolic acids, as determined by HPLC, remained stable throughout fermentation, with average values of 4764 and 1807 mg kg−1, respectively. Finally, sensory analysis revealed the rich aromatic character of Tsounati variety, highlighting its potential to be used for Greek-style table olive production.

Goat milk production and processing are key agricultural activities of significant economic importance in Greece. This study employed a metataxonomics approach to investigate the microbiome of goat milk samples collected from geographically diverse farms across Greece during two consecutive lactation periods (2019-2020 and 2020-2021), focusing on indigenous breeds. Complementary chemical and culture-dependent microbiological analyses were performed alongside evaluation of milk fatty acid composition and antioxidant activity. Milk composition analyses showed no significant differences among samples. However, notable variations among samples were observed in several microbial groups enumerated. The farming system primarily influenced the milk content of short-chain fatty acids, with no significant effect on the milk antioxidant capacity. Finally, both classical microbiological and metataxonomic analyses confirmed the presence of indigenous lactic acid bacteria species that are key contributors as starters and/or adjunct cultures in cheese production, and a lower diversity in yeast species compared to bacterial communities.

In the present work, we examined the angiotensin-I-converting enzyme-inhibitory (ACE-I) activity of the water soluble extracts of four long-ripened Feta cheese samples. High activity (>87 %) was determined for all of them. Additionally, we fingerprinted the non-starter lactic acid bacteria (NSLAB) isolated from the cheese samples. All NSLAB isolates were screened for their proteolytic activity and the most proteolytic ones were further evaluated for their ACE-I activity as well as ability to produce gamma-aminobutyric acid (GABA). The NSLAB isolates comprised 130 lactobacilli and 24 enterococci, with the dominant species being Levilactobacillus brevis, Lactiplantibacillus plantarum, Lacticaseibacillus paracasei and Enterococcus faecium. Among them, 40 selected isolates exhibited high proteolytic activity, with 13 lactobacilli and two enterococci exhibiting strong ACE-I activity (>50 %), and six lactobacilli producing GABA. Thus, the hypertension risk associated with overconsumption of Feta cheese because of its high sodium content may be compensated by the anti-hypertensive traits of NSLAB microbiota members, which are active during the long cheese ripening time.

Staka is a traditional Greek sour cream made mostly from spontaneously fermented sheep milk or a mixture of sheep and goat milk. At the industrial scale, cream separators and starter cultures may also be used. Staka is sometimes cooked with flour to absorb most of the fat. In this study, we employed culture-based techniques, amplicon sequencing, and shotgun metagenomics to analyze the Staka microbiome for the first time. The samples were dominated by Lactococcus or Leuconostoc spp. Most other bacteria were lactic acid bacteria (LAB) from the Streptococcus and Enterococcus genera or Gram-negative bacteria from the Buttiauxella, Pseudomonas, Enterobacter, Escherichia-Shigella, and Hafnia genera. Debaryomyces, Kluyveromyces, or Alternaria were the most prevalent genera in the samples, followed by other yeasts and molds like Saccharomyces, Penicillium, Aspergillus, Stemphylium, Coniospotium, or Cladosporium spp. Shotgun metagenomics allowed the species-level identification of Lactococcus lactis, Lactococcus raffinolactis, Streptococcus thermophilus, Streptococcus gallolyticus, Escherichia coli, Hafnia alvei, Streptococcus parauberis, and Enterococcus durans. Binning of assembled shotgun reads followed by recruitment plot analysis of single reads could determine near-complete metagenome assembled genomes (MAGs). Culture-dependent and culture-independent analyses were in overall agreement with some distinct differences. For example, lactococci could not be isolated, presumably because they had entered a viable but not culturable (VBNC) state or because they were dead. Finally, several LAB, Hafnia paralvei, and Pseudomonas spp. isolates exhibited antimicrobial activities against oral or other pathogenic streptococci, and certain spoilage and pathogenic bacteria establishing their potential role in food bio-protection or new biomedical applications. Our study may pave the way for additional studies concerning artisanal sour creams to better understand the factors affecting their production and the quality.

In recent years, an increasing number of industries have been embracing a more sustainable and environmentally friendly approach by adopting materials that are more eco-conscious compared to their previous choices. The food industry is at the forefront of this movement, striving to introduce novel biocompatible and biodegradable materials that can serve various purposes, such as protection agents, supplements, and carriers. Fungal chitosan (FC), has numerous characteristics, such as the lack of allergen animal proteins, consistency in physicochemical characteristics and easy production, while at the same time being an excellent emulsifier. This is why it has gained significant attention from scientists for various applications. In this study, FC particles were formulated using the pH-shifting method, while emulsions were prepared through high-shear homogenization. The emulsions were examined both macroscopically and microscopically. Their droplet size was determined using Static Light Scattering, revealing an average size of approximately 75 mu m. Furthermore, alpha-tocopherol or squalene was successfully encapsulated in these emulsions. Cryogenic Scanning Electron Microscopy (Cryo-SEM) was utilized to visualize the surface of the droplets, and Confocal Laser Scanning Microscopy allowed for the observation of the droplet core. To assess their antioxidant properties, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) colorimetric

L. monocytogenes is the causative agent of listeriosis, a serious foodborne illness. Antimicrobial practices such as disinfectants used for the elimination of this pathogen in the food industry can produce a sublethally injured population fraction.

Cheese is characterized by a rich and complex microbiota that plays a vital role during both production and ripening, contributing significantly to the safety, quality, and sensory characteristics of the final product. In this context, it is vital to explore the microbiota composition and understand its dynamics and evolution during cheese manufacturing and ripening. Application of high-throughput DNA sequencing technologies have facilitated the more accurate identification of the cheese microbiome, detailed study of its potential functionality, and its contribution to the development of specific organoleptic properties. These technologies include amplicon sequencing, whole-metagenome shotgun sequencing, metatranscriptomics, and, most recently, metabolomics. In recent years, however, the application of multiple meta-omics approaches along with data integration analysis, which was enabled by advanced computational and bioinformatics tools, paved the way to better comprehension of the cheese ripening process, revealing significant associations between the cheese microbiota and metabolites, as well as their impact on cheese flavor and quality.

Limosilactobacillus fermentum ACA-DC 179, a strain with well documented probiotic properties, was included in Greek traditional Kaimaki ice cream produced using two different types of milk, namely plain and lactose-free cow milk. L fermentum survived throughout the ice cream manufacturing and storage. Viable counts did not decline during storage at -20 degrees C for 28 days both in plain (approximately 10(6) cfu g(-1)) and in lactose-free (approximately 10(8) cfu g(-1)) Kaimaki. Acidity and pH remained stable during storage, and, regarding fat and protein content, no variations were determined among samples belonging to the same type of ice cream. Melting characteristics of ice cream slightly altered due to strain addition. Ice cream containing L. fermentum was highly acceptable by the panellists evaluating sensory properties. To conclude, ice cream was proved to be a suitable matrix for L. fermentum ACA-DC 179 regarding the production of a probiotic functional food. (C) 2021 Elsevier Ltd. All rights reserved.

One of the main lactic acid bacterial species found in the kefir grain ecosystem worldwide is Lactobacillus kefiranofaciens, exhibiting strong auto-aggregation capacity and, therefore, being involved in the mechanism of grain formation. Its occurrence and dominance in kefir grains of various types of milk and geographical origins have been verified by culture-dependent and independent approaches using multiple growth media and regions of the 16S rRNA gene, respectively, highlighting the importance of their combination for its taxonomic identification. L. kefiranofaciens comprises two subspecies, namely kefiranofaciens and kefirgranum, but only the first one is responsible for the production of kefiran, the water-soluble polysaccharide, which is a basic component of the kefir grain and famous for its technological as well as health-promoting properties. L. kefiranofaciens, although very demanding concerning its growth conditions, can be involved in mechanisms affecting intestinal health, immunomodulation, control of blood lipid levels, hypertension, antimicrobial action, and protection against diabetes and tumors. These valuable bio-functional properties place it among the most exquisite candidates for probiotic use as a starter culture in the production of health-beneficial dairy foods, such as the kefir beverage.

Microbiological and physicochemical parameters of Lebanese Baladi goat milk from six farms were evaluated and 28 Lactobacillus strains were isolated and examined in vitro for their probiotic potential. Goat milk showed a balanced physicochemical composition while variable LAB counts were observed among samples. All isolates were identified as Lactobacillus rhamnosus. They exhibited diverse susceptibility to commonly used antibiotics, none was haemolytic and showed variable antimicrobial activity towards a range of spoilage and pathogenic bacteria. All strains remained unaffected at pH 3 and in the presence of bile salts (0.5%, w/v) for 3 h exhibiting also a partial bile salt hydrolase activity. Selected strains showed low adhesion to HT-29 and Caco-2 cells. Decrease in COX2 mRNA levels and a tendency to an increase in IL10 expression in human monocytes were noticed. This is the first report about probiotic and safety features of Lb. rhamnosus strains isolated from Lebanese Baladi goat milk. (c) 2021 Elsevier Ltd. All rights reserved.

Listeria monocytogenes is the etiological agent of the severe foodborne disease listeriosis. Important insight regarding the physiology and the infection biology of this microorganism has been acquired in the past 20 years. However, despite the fact that L. monocytogenes coexists with various microorganisms throughout its life cycle and during transmission from the environment to foods and then to the host, there is still limited knowledge related to the impact of surrounding microorganisms on L. monocytogenes ' biological functions. In this study, we showed that L. monocytogenes modulates specific biological activities (i.e., growth and virulence potential) as a response to coexisting microorganisms and differentially alters the expression of virulence-associated genes when confronted with different bacterial genera and species. Our work suggests that the interaction with different bacteria plays a key role in the survival strategies of L. monocytogenes and supports the need to incorporate biotic factors into the research conducted to identify mechanisms deployed by this organism for establishment in different environments.

Artisanal cheeses, in particular those prepared from raw milk, are the most commonly used ecosystems to mine microorganisms with both technological and human-health related potential. In the present study, the microbiota of two Greek artisanal cheeses, the PDO Kalathaki and the non-PDO Melichloro, was explored via classical microbiological analysis. Lactic acid bacteria isolated mainly belonged to the genus Enterococcus (66%) and to a lesser degree to Pediococcus (15%), Leuconostoc (8%), Lactobacillus (6%) and Lactococcus (5%). From the 112 initial isolates, 32 were selected and studied for their probiotic potential, i.e. safety traits, survival under gastrointestinal tract conditions, antimicrobial activity, adhesion, angiotensin I-converting enzyme inhibitory activity and immunomodulation of human monocytes. Two isolates, namely Lactobacillus brevis ACA-DC 1705 and Leuconostoc mesenteroides ACA-DC 1738, exhibited the most promising probiotic potential due to strong angiotensin I-converting enzyme inhibitory activity and anti-inflammatory modulation of immune cells, respectively, and, thus they could be used as adjuncts in novel functional products.

During the last decade, gluten-free food consumption has become a widespread diet trend due to the awareness of gluten intolerances/allergies, as better diagnostic tools are becoming available, and because of the increased number of consumers following this diet regardless of medical needs. However, production of gluten-free foods comprises technological challenges that have to be addressed. The chapter is initially introducing the concept of gluten-free food production in accordance to current gluten-free product markets and labeling regulations worldwide. The need to improve the quality of gluten-free products highlighting both nutritional and formulations aspects is also examined. In this context, it provides a comprehensive overview of various techniques applied in the production of gluten-free foods for combating the commonly encountered problems related to the elimination of gluten. These techniques include compositional approaches, such as the addition of different ingredients and additives in gluten-free formulations. Additionally, bioprocessing fermentations, novel optimal processing technologies, and transgenic methodologies are discussed as the main emerging technological approaches for affecting physico-chemical, sensory, and nutritional characteristics of gluten-free foods.

Bread is one of the most widely consumed foods in the world and has been an integral part of the human diet for thousands of years. Although yeasts are considered the major leavening agent in bread production, the use of sourdough as a natural starter in bread-making is one of the oldest food biotechnologies. Sourdough has been recently rediscovered and extensively studied as a cell factory able to modify cereals and other dough ingredients to functional and nutritional bread. This chapter provides a comprehensive overview about the sourdough microbiota, as this has been described so far by both conventional and omics approaches, as well as its functionality with regard to the technological properties of bread, such as texture, flavor, shelf-life, and nutritional value. Moreover, the emerging use of alternative raw materials for sourdough and bread production, the application of nonconventional starters, along with the adaptation of existing and the development of novel technologies in tailor-made bread types, as for example in the case of gluten-free bread, are also considered.

The characteristics of fermented milk are affected by the type of milk used and the microorganisms involved in the fermentation process. Goat milk has been widely suggested as a possible alternative to cow milk in allergic subjects, because of the high genetic variability in alpha-s1 casein (CSN1S1) content, which is associated with different technological and nutritional properties of milk. The aim of the study was to evaluate the suitability of goat milk with low and high CSN1S1 to produce fermented milk. In addition, the performance as starter of selected Lactobacillus paracasei FS109 strain compared to no-selected L. paracasei strains was investigated. Initially, the selected L. paracasei FS109 strain was tested for adhesion ability to HT-29 and Caco-2 cells and immunomodulation effect. Then, the strain was used to produce fermented milk from goat milk with a low and high casein CSN1S1 genotype. The results indicated that greater acidifying activity was obtained for L. paracasei FS109 after 24 h of fermentation than the other two strains tested independently by the CSN1S1 genotype. L. paracasei FS109 grew well during fermentation, reaching a higher value (>8.5 log CFU/mL). Interestingly, the same strain maintained a high viable population (about 9 log CFU/mL) during the 30-day cold storage of the product. The present study shows for the first time the suitability of the goat milk with low CSN1S1 genotypes to produce fermented milk and highlight the importance of strain selection in determination of technological and beneficial traits. Combining goat milk with low CSN1S1 and selected strains could be a strategy of improving traditional and functional fermented milk market.

In the present study, 49 yeast strains previously isolated from cv. Kalamata table olive fermentation were assessed for their probiotic potential and technological characteristics. The probiotic assays included the in vitro survival in simulated gastric and pancreatic digestions, surface adhesion to the intestinal cell line Caco-2, hydrophobicity, autoaggregation and haemolytic activity. The technological features of the strains were also elucidated in terms of enzymatic activity and susceptibility to diverse salt levels (0-250 g/L) and pH values (3.5, 5.0, and 6.5). The obtained results indicated that during the simulated gastric and pancreatic digestions, 42 out of the 49 yeast strains presented overall survival rate higher than 50%, while 24 strains showed survival percentage higher than 70% at the end of the digestions. Furthermore, the majority of the assayed strains presented hydrophobicity percentage higher than 75%, while the autoaggregation ability ranged between 72 and 91%. None of the strains showed haemolytic activity. The majority of the strains presented high tolerance to salt with some strains exhibiting tolerance even at salt concentrations higher than 200 g/L. Concerning the enzymatic activity, 45 strains presented valine and cystine arylamidase activity, while positive reactions for the enzymes 13 and a-glucosidase were observed for 27 and 14 strains, respectively. Moreover, 11 strains presented a-galactosidase and alkaline phosphatase activity. From the total number of studied yeasts, the strain Y34 belonging to Saccharomyces cerevisiae presented positive results in the majority of both probiotic and technological assays and thus it could be considered a potential starter either as single or as combined culture with lactic acid bacteria in the fermentation of Greek-style natural black olives.

The increased consumers' interest on the positive role of food in wellbeing and health underscores the need to determine new probiotic microorganisms. Triggered by the fact that artisanal food products can be a valuable source of novel probiotic strains, 106 lactic acid bacteria, all isolated from traditional Greek dairy products, namely Feta, Kasseri, Xynotyri, Graviera, Formaela, Galotyri, and Kefalotyri cheeses as well as yogurt and milk, were studied for probiotic properties. Based on their survival at pH 2.5 and their stability in the presence of bile salts, 20 strains were selected for further analysis. These strains exhibited diverse susceptibility to commonly used antibiotics, while none was hemolytic. Seven out of the 20 strains produced functional bile salt hydrolases in vitro. The only antimicrobial activity detected of Streptococcus thermophilus ACA-DC 26 against the oral pathogen Streptococcus mutans LMG 14558T was attributed to compound(s) of proteinaceous nature. Two Lactobacillus plantarum strains, namely ACA-DC 2640 and ACA-DC 4039, displayed the highest adhesion according to a collagen-based microplate assay and by using ΗΤ-29 and Caco-2 cells. Co-cultivation of THP-1 cells with selected strains indicated a tendency for anti-inflammatory modulation by Lactobacillus plantarum ACA-DC 2640 as well as Streptococcus thermophilus ACA-DC 26 and ACA-DC 170, as shown by an increase in IL10 mRNA levels. Moreover, milk cell-free supernatants of Lactobacillus plantarum ACA-DC 2640 and ACA-DC 4039 exhibited strong angiotensin I-converting enzyme inhibition. To conclude, new isolates presenting interesting probiotic features were described and should be further investigated as health-promoting factors.