Queijo Serra da Estrela is a PDO Portuguese cheese produced through coagulation of raw ewe’s milk using cardoon (Cynara cardunculus L.) flowers. The present research was aimed at depicting an up-to-date and comprehensive overview of the microbiota of Queijo Serra da Estrela cheese. To this end, viable counting and metataxonomic analysis were carried out on cheeses sampled from four Portuguese artisan producers. Physico-chemical and morpho-textural analyses were also performed, together with the analysis of volatile organic compounds (VOCs). Finally, non-starter lactic acid bacteria (NSLAB) isolated from the cheeses were characterized for their enzymatic activities using a semi-quantitative method. According to the metataxonomic analysis, Lactococcus lactis and Lactococcus piscium were the species occurring at the highest relative abundance. The isolates collected from the cheeses were assigned to Enterococcus durans, Enterococcus faecalis, Enterococcus faecium, Enterococcus lactis, Levilactobacillus brevis, Latilactobacillus graminis, Leuconostoc mesenteroides, and the Lacticaseibacillus casei group. The enzymatic characterization of these cultures highlighted esterase, aminopeptidase, acid phosphatase, beta-galactosidase, alpha-glucosidase, and beta-glucosidase among the major enzymatic activities. Fungal populations were dominated by Debaryomyces hansenii and Kurtzmaniella zeylanoides; however, species rarely found in cheese (e.g., Candida boidinii, Vishniacozyma victoriae, and Starmerella) were also detected. The volatile compounds characterizing the analyzed cheeses were carboxylic acids and esters, followed by carbonyl compounds and alcohols.

Milk coagulants prepared by maceration of flowers harvested from both spontaneous and cultivated Onopordum tauricum Willd. and a commercially available coagulant obtained from Cynara cardunculus L. (control) were assayed for small-scale manufacturing of Caciofiore, an Italian specialty raw ewe’s milk cheese produced in a family run dairy farm located in the Marche region (Central Italy). The microbiota of the three thistle-based milk coagulants and their effect on the microbial dynamics of raw milk cheeses during fermentation and maturation (from day 0 up until day 60) were investigated through a combined approach based on viable counting and Illumina DNA sequencing. In both the control and experimental cheeses, despite the slight differences emerged depending on the coagulant used, Lactococcus lactis and Debaryomyces hansenii were the prevalent species among bacteria and fungi, respectively. Moreover, raw ewe’s milk was the main factor affecting the evolution of both the bacterial and fungal microbiota in all cheeses. The overall similarities between control and experimental cheeses herein analyzed supports the exploitation of Onopordum tauricum Willd. as an alternative milk coagulating agent for production of Caciofiore and, more in general, raw ewe’s milk cheeses.

Sea fennel (Crithmum maritimum L.) is a strongly aromatic herb of the Apiaceae family, whose full exploitation by the modern food industry is of growing interest. This study aimed at investigating the microbiological quality, volatile profile, and sensory traits of sea fennel spices produced using room-temperature drying, oven drying, microwave drying, and freeze drying. All the assayed methods were able to remove moisture up until water activity values below 0.6 were reached; however, except for microwave drying, none of the assayed methods were effective in reducing the loads of contaminating microorganisms. The metataxonomic analysis highlighted the presence of phytopathogens and even human pathogens, including members of the genera Bacillus, Pseudomonas, Alternaria, and Cryptococcus. When compared to fresh leaves, dried leaves showed increased L* (lightness) and c* (chroma, saturation) values and reduced hue angle. Dried leaves were also characterized by decreased levels of terpene hydrocarbons and increased levels of aldehydes, alcohols, and esters. For the sensory test, the microwave-dried samples obtained the highest appreciation by the trained panel. Overall, the collected data indicated microwave drying as the best option for producing sea fennel spices with low microbial loads, brilliant green color, and high-quality sensory traits.

This study provides a comprehensive characterization of a traditional Macedonian brined raw goat's milk cheese, focusing on how seasonal production (spring vs. autumn) shapes its physicochemical traits, morpho-textural properties, and microbial ecology. Cheese samples produced in autumn exhibited stronger acidification, higher titratable acidity, lower water activity, and higher NaCl content than spring cheeses, reflecting variability associated with artisanal, non-standardized processing. Texture profile analysis showed that cohesiveness and springiness were significantly affected by season, whereas hardness and adhesiveness remained comparable across batches. A combined culture-dependent and 16S rRNA gene-based metataxonomic approach revealed seasonally distinct microbiota. Viable microbial populations composed of mesophilic aerobes (up to 6.51 log cfu g^-1 at 60 days of ripening), presumptive mesophilic lactobacilli and lactococci (up to 6.51 and 7.18 log cfu g^-1 at 60 days of ripening, respectively), presumptive coagulase-negative and coagulase-positive staphylococci (up to 6.97 and 1.76 log cfu g^-1 at 60 days of ripening, respectively), and Enterobacteriaceae (up to 1.25 log cfu g^-1 at 60 days of ripening) were detected. Spring cheeses were characterized by higher relative abundances of Carnobacteriaceae, Enterococcus, Serratia, and Tetragenococcus halophilus, whereas autumn cheeses were dominated by Companilactobacillus and Lactococcus, alongside various Enterobacteriaceae. Beta-diversity analysis confirmed significant clustering of cheese microbiota by season. In total, 134 lactic acid bacteria isolates were obtained from the dairy environment, milk, brine, and cheese. These included Lactococcus lactis, Levilactobacillus brevis, multiple Enterococcus species, Pediococcus pentosaceus, Lacticaseibacillus paracasei, Marinilactibacillus psychrotolerans, and Companilactobacillus alimentarius. Many isolates showed strong proteolytic activity, several produced exopolysaccharides, and a subset exhibited lipolytic capacity, underscoring their technological potential. Screening for the histidine decarboxylase gene hdcA revealed that only the C. alimentarius isolate was positive, excluding this strain from consideration as an adjunct culture, whereas all other isolates were hdcA-negative and therefore suitable candidates from a histamine-safety perspective. Overall, this integrated analysis highlights the rich microbial diversity and seasonal variability of this artisanal cheese and supports the selection of safe autochthonous lactic acid bacteria for future product valorization.

Background/Objectives: This study was aimed to investigate the safety profile of traditional Montenegrin Njeguški cheese by quantifying genes associated with resistance to clinically important antibiotics. Methods: Samples of Njeguški cheese were sourced from three artisan producers in Montenegro, identified as A, B, and C, with three individual batches selected per producer. Quantitative PCR (qPCR) was performed on bacterial DNA extracted directly from samples to detect genes encoding resistance to macrolide–lincosamide–streptogramin B (MLS_B) [erm(A), erm(B), erm(C)], vancomycin (vanA, vanB), tetracyclines [tet(M), tet(O), tet(S), tet(K), tet(W)], β-lactams (mecA, blaZ), aminoglycosides [aac (6′)-Ie aph (2″)-Ia], and carbapenems (bla_KPC, bla_OXA-48, bla_NDM-1, bla_GES, and bla_VIM). Results: Among the MLS_B resistance genes, erm(B) was detected in all samples, erm(C) was present only in those from producer B, while erm(A) was found exclusively in batch 3 from producer C. Tetracycline resistance genes were widely distributed, except for tet(O), which was absent in batch 3 from producers A and B. Regarding β-lactam resistance, both blaZ and mecA were consistently detected across all samples, with statistically significant differences observed between producers. None of the samples tested positive for vancomycin resistance genes or the aminoglycoside resistance gene, regardless of producer. Among the carbapenemase genes analyzed, bla_NDM-1 was the only one detected, found in most samples from producers B and C. Conclusions: This research provides the first risk assessment of artisanal and commercial Njeguški cheese regarding antimicrobial resistance genes. The findings offer valuable insights to enhance the microbiological safety of traditional Montenegrin cheeses, supporting consumer confidence in local and international markets.