Search Results (325)

This study investigated the microbiological composition and antimicrobial resistance (AMR) profiles of artisanal goat and sheep milk cheeses produced in Poland. Ten raw milk cheeses (five each from goat and sheep milk) were analyzed using a combined approach involving culture-dependent enumeration, 16S rRNA gene sequencing, and antibiotic susceptibility testing. Microbial counts revealed substantial variability among the samples, with lactic acid bacteria (LAB) dominating the microbiota. Taxonomic analysis confirmed the predominance of Lactococcus, Streptococcus, and lactobacilli, although marked intra-group heterogeneity was observed. Multivariate analyses indicated that sample-specific factors had a greater influence on microbiome composition than milk origin. Among 170 isolates, 28.7% were classified as multidrug-resistant (MDR), being most prevalent in Enterobacterales (100%) and Enterococcus spp. (73%), whereas LAB exhibited low resistance levels (16.2%). Resistance was most frequently associated with aminoglycosides and β-lactams. The resistance results were interpreted according to CLSI guidelines. These findings demonstrate that artisanal cheeses harbor complex, dynamic microbial ecosystems that may serve as reservoirs of antimicrobial resistance. The results highlight that environmental and technological factors, rather than milk source alone, are key drivers of both microbiome structure and resistance distribution, underscoring the need for targeted AMR monitoring in traditional dairy products. Full article

While industrial-scale dairy fermentations often employ pasteurized milk as the substrate, many farmhouse and traditional production practices apply raw milk derived from a variety of mammals. Certain artisanal production systems rely on the autochthonous microbiota of the milk, fermentation vessels, equipment and/or environment to initiate milk coagulation. While the technological properties of lactic acid bacteria associated with dairy fermentations are well described, their interactions with other organisms during fermentation and cheese ripening are poorly investigated. This study presents an overview of the microbial ecology of raw and pasteurized milk used in the production of Irish farmhouse cheeses using metagenomic and culture-based approaches. Metagenomic analysis of four raw milk-derived cheeses established the dominant presence of either lactococci or Streptococcus spp. and with a secondary population of various lactobacilli. Interestingly, the Brie sample was also demonstrated to possess significant proportion of Hafnia spp. This was corroborated in culture-based analysis where Hafnia isolates were also identified. Furthermore, we report on the motility phenotype, lactose utilization ability and metabolic products of isolates of Hafnia paralvei and Hafnia alvei, and determine that these strains could grow in a non-antagonistic manner on plates with strains of Lactococcus lactis and Streptococcus thermophilus. As artisanal and farmhouse production systems are often associated with protected or regionally significant products, it is essential to develop a clear understanding of the microbial communities within and the complex relationships between the community members. Full article

The global functional food market continues to expand, and edible mushrooms are emerging as high-value ingredients due to their rich nutritional profile, particularly their high protein content, balanced amino acid composition, and dietary fiber. This growing industrial interest is reflected in the registration of more than 322 patents in the past five years according to the Derwent Innovation patent database. Recent advances include the integration of precision mycology (PM) and omics-based approaches, such as CRISPR-Cas9, into solid-state fermentation and submerged fermentation, enabling improvements in natural umami flavor and bioactive composition. Innovative products, including meat analogues with fibrous textures, functional beverages such as kombucha and juices, and fermented dairy products such as yogurts and cheeses, have been formulated to deliver prebiotic, antioxidant, and immunomodulatory properties. Future trends indicate a shift towards the production of high-value nutraceutical peptides and biomass, together with the adoption of artificial intelligence (AI) and the Internet of Things (IoT) to enhance bioreactor automation and scalability. Nevertheless, significant challenges remain, including regulatory constraints, the scarcity of clinical validation in humans, and the need for strict control over the bioaccumulation of heavy metals in mushroom-derived raw materials. Addressing these gaps will be critical for advancing regulatory frameworks, improving industrial standardization, and supporting the translational development of mushroom-based functional foods. Full article

Drying significantly influences the quality of micellar casein (MC) powder. This study investigated the effects of three pre-freezing temperatures (−20 °C, −80 °C, and liquid nitrogen) prior to freeze drying on the structure and rennet-induced gelation properties of MC powder. The results showed that as the pretreatment temperature decreased, the degree of disruption to the secondary and tertiary protein structures was reduced, while the particle size gradually increased. In terms of rennet-induced gel properties, the untreated raw MC consistently outperformed all MC powder samples. Among the MC powders, the sample pre-frozen at −80 °C and then freeze-dried (FD-80) exhibited the highest gel strength and a relatively shorter rennet coagulation time. The observed microstructures of the rennet-induced gel were consistent with the rheological results, showing that samples with smaller particle sizes formed more regular and compact gel networks. In conclusion, the MC powder prepared via pre-freezing at −80 °C and then freeze-drying better preserved protein structure and demonstrated superior rennet-induced gel properties, which were closely related to particle size. This study provides theoretical insights for the application of MC powder in products such as cheese, processed cheese, and protein-fortified foods. Full article

Rolled cheeses are a traditional specialty of the Vojvodina region in Serbia, produced through an artisanal process passed down across generations. This study evaluated the impact of the addition of selected herbs (a mixture of oregano and basil and chives added separately) on the microbiological, physicochemical, and sensory characteristics of rolled pasta filata cheese. Cheeses, both with and without herbs, were vacuum packed and stored at 4 °C for 60 days. The addition of oregano and basil significantly reduced aerobic mesophilic bacteria, Enterobacteriaceae, and Escherichia coli, while Salmonella spp. and Listeria monocytogenes remained undetectable throughout storage. Physicochemical analyses classified the cheeses as full-fat, semi-hard, with at least 45% milk fat in dry matter, and moisture in fat-free matter between 54% and 69%. All variants exhibited uniform shape, intact appearance, and a compact layered structure, while herbal-enriched cheeses developed a distinctive aroma and flavor. Sensory evaluation showed that all cheese types remained acceptable for up to 40 days, with minor deviations at day 60. Overall, the herbal addition enhanced sensory appeal, created new flavor profiles, and improved microbiological stability, demonstrating its potential as a natural strategy to extend the shelf life of traditional Serbian rolled pasta filata cheese. Full article

This study presents a genome-resolved shotgun metagenomic analysis of artisanal raw-milk goat cheese from the Masurian region of Poland, addressing the limited understanding of strain-level diversification and functional restructuring during traditional cheese ripening. While microbial succession in cheese has been widely described, comprehensive genome-resolved analyses integrating strain-level genomic heterogeneity, pathway reweighting, and mobile genetic elements in artisanal goat cheese remain scarce. By combining taxonomic profiling with metagenome-assembled genome (MAG) reconstruction and pathway-level functional analysis, we characterised microbial succession and genome plasticity across ripening stages. Genome reconstruction yielded 37 MAGs during early ripening and 141 MAGs in mature cheese, revealing increased genome recoverability and pronounced strain-level heterogeneity within dominant taxa, including Lactiplantibacillus plantarum, Lacticaseibacillus paracasei, and Lactococcus lactis. Alpha diversity increased in mature samples, consistent with progressive community restructuring. Functional profiling demonstrated coordinated metabolic reweighting, particularly within carbohydrate metabolism, while amino acid and lipid metabolism remained proportionally stable. Genome-resolved analyses further identified tetracycline- and sulfonamide-associated resistance determinants and diverse bacteriophages targeting lactic acid bacteria, highlighting the role of mobile genetic elements in horizontal gene transfer and microevolutionary adaptation during ripening. Full article

The aim of the research was to assess changes in the bioactive status of organic yoghurts produced in the spring/summer season from Simmental cows’ bulk milk during 28-day refrigerated storage, including whey proteins, lipophilic vitamins, and free fatty acids, and to interpret these changes not only in terms of compositional stability but also regarding their nutritional significance, as evaluated using the IYQ (Index of Yoghurt Quality) for vitamins. Raw milk was found to be a significantly richer source of biologically active compounds compared with milk subjected to heat treatment. During the 28-day refrigerated storage of the yoghurts, unfavourable alterations were observed in the levels of selected bioactive components belonging to both the protein and lipid fractions. A reduction in the concentration of the analyzed proteins and vitamins was observed, ranging from 2% for vitamin D₃ to 38% for lactoferrin, while the content of free fatty acids increased, from 8% for monounsaturated free fatty acids (MUFFAs) to 39% for short-chain free fatty acids (SCFFAs). The most pronounced changes were observed in lactoferrin content (p ≤ 0.01), whereas vitamin D₃ exhibited the highest stability throughout the storage period. The stability of vitamin D₃ was further confirmed using the Index of Yoghurt Quality (IYQ). Despite the significant changes observed in the bioactive profile, the yoghurts retained high sensory quality throughout the entire storage period. This indicates that alterations in bioactive status did not compromise the sensory quality of the product, even after 28 days of storage (i.e., at the end of the shelf life). The obtained results indicate the feasibility of developing organic milk processing directly at the farm level while preserving the nutritional value of the products. The possibility of processing organic milk not only into cheese but also into fermented dairy beverages, particularly yoghurts, is of key importance for farmers aiming to diversify production, increase added value, and improve the economic sustainability of small-scale organic farms. Full article

Background/Objectives: Milk and dairy products are among the most relevant foods both nutritionally and commercially. Costa Rica stands out as one of the main producers and consumers of dairy products in Central America. However, in recent years, the use of antibiotics in the livestock industry has increased, with implications for public health and food security, generating a need to monitor residues of these drugs in food. The present research focuses on developing a liquid chromatography method for the simultaneous quantification of penicillin G (PEN) and cloxacillin (CLO) in raw and commercial bovine milk, as well as in various dairy products, including fresh cheese and liquid yogurt. Methods/Results: During the validation of the methodology, average sensitivities of (960 ± 8)·10¹ mg L⁻¹ and (1580 ± 9)·10¹ mg L⁻¹ were achieved for PEN and CLO, respectively. Determination coefficients of 0.9995 and 0.9998 were also achieved, respectively. The limits of detection (LOD) and quantification (LOQ) for PEN and CLO were (0.330 ± 0.025) mg L⁻¹ and (0.65 ± 0.12) mg L⁻¹, (1.10 ± 0.083) mg L⁻¹ and (2.2 ± 0.4) mg L⁻¹, respectively, on both accounts. Recoveries were 68–77%, 92–106%, and 78–112% for PEN and 57–79%, 99–114%, and 95–120% for CLO in milk, cheese, and yogurt, respectively, across all three concentration levels evaluated. The precision of the method, in terms of reproducibility, was assessed for liquid yogurt (3–12% RSD_R for PEN and 4–12% RSD_R for CLO) and in cheese (8–14% RSD_R for PEN and 4–12% RSD_R for CLO). Nineteen bovine milk samples from the Cartago area were evaluated, including commercial and milk samples. Additionally, cheese (n = 17) and yogurt samples (n = 8) were analyzed. Conclusions: None of the samples showed detectable signals of the antibiotics. In addition, antibiotic sensitivity testing was performed on n = 9 Lactic Acid Bacteria (LAB) strains isolated from the raw milk samples, revealing the presence of some resistant traits to several antibiotics, including β-lactams. Full article

The aim of this work was to evaluate the microbiological quality of Spanish aged cheeses and the antimicrobial resistance of enterococci, staphylococci and Enterobacterales. A total of 60 aged cheeses produced in northern Spain were collected at the retail level. Mesophiles, lactic acid bacteria, staphylococci, enterococci, Enterobacterales, and yeast counts were determined. More microbial diversity was found in raw milk cheeses than in those elaborated with pasteurized milk. In general, lactic acid bacteria were the dominant microorganism, mainly Lactiplantibacillus lactis. High resistance rates were observed in E. faecalis strains isolated from raw milk cheeses (74.42%), being 9.30% multi-resistant. The dominant staphylococci found was Staphylococcus equorum. Multi-resistant S. equorum strains were isolated both from raw (1.69%) and pasteurized milk cheeses (9.09%). Hafnia alvei was the predominant bacterium in raw milk cheeses. Fifteen Enterobacterales strains, isolated from raw milk cheeses, showed multi-resistance (37.5%), and seven strains were ESBL producers (17.5%). Escherichia coli was only isolated from 5. 56% of raw milk cheeses, but all of them were extended-espectrum B-lactamase (ESBL) producers. The dominant yeast was D. hansenni, followed by Kluyveromyces lactis. Full article

Enterococci are ubiquitous lactic acid bacteria frequently detected in dairy environments, where they represent an important component of the non-starter lactic acid bacteria community, particularly in artisanal cheeses produced from raw milk. Due to their metabolic versatility, enterococci may contribute to cheese ripening and the development of characteristic sensory attributes; however, their technological relevance is accompanied by growing concern regarding their role as opportunistic pathogens and reservoirs of antimicrobial resistance. This review critically summarizes current knowledge on antimicrobial resistance in enterococci isolated from milk and dairy products, with emphasis on both intrinsic and acquired resistance traits and their reported prevalence across different dairy matrices and geographical regions. Particular attention is given to artisanal cheeses, in which heterogeneous and region-specific resistance patterns have been described. Advances in whole-genome sequencing have substantially improved understanding of the genetic basis of antimicrobial resistance in dairy enterococci and have largely corroborated earlier findings obtained through phenotypic antimicrobial susceptibility testing combined with targeted resistance gene detection. Nevertheless, available data remain fragmented due to variability in study design, analytical approaches, and reporting practices. Overall, the evidence highlights the need for harmonized surveillance strategies integrating phenotypic and genomic data within a One Health framework to improve risk assessment and to better understand the role of dairy enterococci in the dissemination of antimicrobial resistance along the food chain. Full article

Large amounts of agro-industrial residues—such as grape pomace, olive mill wastewater, wheat straw, and cheese whey—pose disposal challenges and generate substantial environmental and economic burdens. Incorporating these by-products into ruminant diets may reduce feeding costs while supporting sustainability within a circular bioeconomy. Two experiments were conducted to evaluate: (i) the characteristics of a mixed raw agro-industrial by-product silage (BPS) in cylindrical bale silos (50 kg) and (ii) its effects as dietary supplementation on metabolic profile, oxidative status, milk yield, and milk quality in lactating goats. The BPS was formulated from raw wheat straw, grape pomace, olive mill wastewater, and cheese whey and tested at a 30% inclusion level (dry-matter basis). The combined by-products produced in 50 kg cylindrical bale silos were positively characterized and exhibited a nutritionally suitable silage with relevant antioxidant potential. Dietary BPS improved oxidative status, as evidenced by increased TAS and vitamin E and reduced ROMs, and positively influenced lipid and immunological blood markers of goats. Milk yield was higher in goats receiving the BPS. Moreover, milk quality was improved through a more favorable fatty acid profile, higher vitamin E content, reduced cholesterol levels, and enhanced oxidative stability, as evidenced by lower TBARS values. Overall, BPS supplementation enhanced animal health indicators and milk nutritional properties, demonstrating that this silage can contribute to more sustainable dairy goat production while offering potential benefits for human nutrition. Full article

Artisanal colonial cheese (ACC) produced from raw milk is a rich reservoir of autochthonous lactic acid bacteria (LAB), but strain-level evidence supporting safe downstream application and technological stability remains limited. In this study, 10 LAB isolates from ACC were screened for phenotypic safety, antimicrobial susceptibility, and probiotic-related traits, and their viability was further assessed after inulin-based spray-drying microencapsulation under different storage temperatures. All isolates showed no hemolytic or mucinolytic activity and did not produce gelatinase, supporting an initial safety profile, and all strains were sensitive to at least two antimicrobial classes. Strain prioritization identified Lacticaseibacillus casei LAB06, LAB09, and LAB10 and Lactiplantibacillus plantarum LAB03 as the most robust candidates for downstream development because they maintained stable cell counts throughout simulated gastrointestinal digestion. Inulin spray-drying yielded structurally stable microcapsules and supported refrigerated storage, with substantially lower viability losses at 4 °C than at 25 °C; notably, L. plantarum LAB01 and LAB02 showed the best refrigerated shelf-life, remaining above 6.0 log CFU/g after 45 days. Together, these results position ACC as a source of promising LAB candidates and highlight cold-chain-compatible microencapsulation as a strategy to support safe functional food development with potential public health benefits. Full article

This research was conducted on small farms in Republika Srpska, an entity of Bosnia and Herzegovina. Data were collected through direct interviews on five farms, each with 8–15 dairy cows, which at some point diversified their production from selling raw milk to processing and selling fresh cheese. Due to low productivity and limited economies of scale, calculated indicators such as net present value, internal rate of return, and payback period are insufficient to consider traditional milk production economically justified. However, further analysis using Monte Carlo simulations and the real options method demonstrated that diversifying production into cheese processing is economically feasible, as confirmed by the strategic net present value calculated using Black–Scholes and binomial approaches. The results indicate that small, extensive family farms should focus on higher levels of product finalization. Although their production volumes are limited and they are not cost-competitive in raw milk markets, they gain a competitive advantage by adding value through their own labor and selling products via short supply chains. Diversification enables these farms to improve profitability, achieve financial stability, and strengthen market positioning, demonstrating that value addition is essential for the sustainability of small-scale dairy enterprises. Full article

Colonial cheese production represents a valuable cultural and economic activity in southern Brazil. This study evaluated the effect of oral supplementation of dairy cows with an essential oil blend (EOB)—a combination of eucalyptus oil, peppermint oil, and menthol crystals—on the chemical composition and quality parameters of Colonial cheese during 21 days of ripening. Nine dairy cows were randomly assigned to three groups: control, EOB3.6 (3.6 g/cow/day), and EOB7.2 (7.2 g/cow/day). Milk from each treatment was used to produce Colonial cheeses, which were analyzed for physicochemical composition, texture, color, lipid profile, thiobarbituric acid reactive substances (TBARS), and microbiological quality at different ripening stages. Data were analyzed by analysis of variance (ANOVA) using SAS^® software, following verification of normality and homogeneity of variances. When assumptions were met, repeated-measures ANOVA was applied, and means were compared using Tukey’s test (p < 0.05). Sensory data were evaluated by ANOVA using XLSTAT^® (Addinsoft, Paris, France). EOB supplementation maintained the physicochemical integrity of the cheeses, with a gradual increase in fat content during maturation (40 g/100 g at 21 days, p < 0.05). At seven days, the EOB7.2 treatment showed lower lipid oxidation (TBARS = 0.063, p < 0.05), indicating antioxidant potential. Significant interactions between treatment and maturation were observed for color parameters and polyunsaturated fatty acids (PUFA) (p < 0.05). Cheeses from EOB7.2 presented higher saturated fatty acids (SFA) and lower unsaturated fatty acids (UFA) compared with the control (p < 0.05). No Salmonella spp. or Staphylococcal enterotoxins were detected. Counts of coagulase-positive Staphylococcus, molds, and yeasts remained stable, while Escherichia coli counts were lower in EOB-supplemented cheeses throughout ripening. Overall, EOB supplementation improved oxidative stability and microbiological safety without compromising the technological or compositional quality of Colonial cheese. Full article

The presence of trace and toxic elements in milk and dairy products is an important food safety issue, as contamination can occur along the dairy supply chain and may be influenced by animal species, production system, and processing conditions. This study aimed to investigate and compare the multi-elemental composition of milk and selected dairy products obtained from organic, conventional, and commercial production systems in north-western Romania. A total of 307 samples, including raw milk from different animal species (cow, goat, buffalo, donkey) as well as yogurt, cheese, and mozzarella, were collected from farms and retail outlets. Samples were subjected to standardized microwave-assisted acid digestion and analyzed for toxic and essential elements (Pb, Cd, Hg, As, Cr, Ni, Al, Sn, Cu, and Zn) using inductively coupled plasma mass spectrometry (ICP–MS), with quality assurance ensured through certified reference materials and proficiency testing. The results indicated low concentrations of toxic metals across all dairy matrices, with Pb ranging from 0.0047 to 0.0117 mg/kg, Cd from 0.0008 to 0.0011 mg/kg, and As from 0.0007 to 0.0664 mg/kg, depending on animal species and production system. Mercury was consistently below the limit of detection in all datasets (LCD = 100%). Essential and transition elements were systematically quantified, occurring within expected ranges (Al: 0.021–0.264 mg/kg; Cu: 0.078–0.270 mg/kg; Zn: 3.245–7.963 mg/kg; Sn ≈ 0.0030–0.0035 mg/kg). All toxic element concentrations were below the maximum limits established by European Union legislation. Variations in elemental profiles were observed between animal species and production systems, with organic cow milk showing the most homogeneous composition. All toxic element concentrations were below the maximum limits established by European Union legislation. Overall, the findings confirm the safety of the analyzed dairy products and emphasize the relevance of multi-elemental monitoring as a practical tool for dairy supply chain surveillance and risk assessment. Full article