This study aimed to calculate the proportion of antibiotic resistance profiles of Enterococcus faecium, E. faecalis, and E. durans isolated from traditional sheep and goat cheeses obtained from a selected border area of Slovakia with Hungary (region Slanské vrchy). A total of 110 Enterococcus sp. were isolated from cheese samples, of which 52 strains (E. faecium (12), E. faecalis (28), E. durans (12)) were represented. After isolation and identification by polymerase chain reaction and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry, the enterococci (E. faecium, E. faecalis, and E. durans) were submitted to susceptibility tests against nine antimicrobial agents. In general, strains of E. faecalis were more resistant than E. durans and E. faecium. A high percentage of resistance was noted in E. faecalis to rifampicin (100%), vancomycin (85.7%), teicoplanin (71.4%), erythromycin (71.4%), minocycline (57.1%), nitrofurantoin (57.1%), ciprofloxacin (14.3%), and levofloxacin (14.3%). E. durans showed resistance to rifampicin (100%), teicoplanin (100%), vancomycin (66.7%), erythromycin (66.7%), nitrofurantoin (66.7%), and minocycline (33.3%), and E. faecium showed resistance to vancomycin, teicoplanin, and erythromycin (100%). Multidrug-resistant strains were confirmed in 80% of the 52 strains in this study. Continuous identification of Enterococcus sp. and monitoring of their incidence and emerging antibiotic resistance is important in order to prevent a potential risk to public health caused by the contamination of milk and other dairy products, such as cheeses, made on farm level.

Consumption of sheep’s and goat’s milk and cheese is currently increasing. The production process of these types of cheese is being carried out by traditional domestic production at farm level. However, knowledge in the field of hygiene, technology and health safety of cheeses are still insufficient. This study aimed to examine the physical and chemical quality and microbiological safety of sheep’s and goat’s milk and cheeses made from them. The month of milking influenced the content of milk components (p < 0.001) in sheep’s milk and goat’s milk, but no changes in SCC content during the examined period were found (p > 0.05). Level of contamination by Enterobacteriaceae sp. and coagulase-positive staphylococci was lower than 5 log CFU/mL in sheep’s and goat’s milk. During the ripening time, the number of lactic acid bacteria significantly raised (p < 0.001). Ripening time statistically changed (p < 0.001) not just the microbial safety of cheeses but also the color (p < 0.01). Under the applicable regulations, the analyzed samples were evaluated as suitable for human consumption.

The study aimed at determining the prevalence antibiotic resistance of species – identified enterococci and Escherichia (E.) coli isolated from typical fresh Slovak cheese, bryndza. Antibiotic resistance of enterococci was determined by disk diffusion method. Of isolated enterococci, 240 were obtained from bryndza cheese. The first two decimal dilutions from 24 bryndza cheese samples purchased at supermarkets in Košice (0.1 mL) were spread on the surface of Slanetz and Bartley agar and incubated for 48±2 h at 37±1°C. Species identification of enterococci and E. coli was detected by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) based on bacterial protein profiling. The following species of enterococci were identified by MALDI-TOF MS: Enterococcus (Ent.) faecalis (22 strains), Ent. faecium (18 strains), Ent. sacharolyticus (6 strains), Ent. gilvus (4 strains), Ent. durans (9 strains), and Ent. casseliflavus (6 strains). All of the 45 E. coli strains and...

Enterococci are a group of microorganisms that have a controversial position from some scientific points of view. The species of the greatest clinical importance are E. faecalis and E. faecium, which are common agents of nosocomial infections. However, enterococci also have important applications in the dairy industry, as they are used as non-starter lactic acid bacteria (NSLAB) in a variety of cheeses, especially artisanal cheeses. The aim of this study was to determine the presence of representatives from the Enterococcus genus using PCR and MALDI-TOF MS methods on samples of raw milk, processing environment swabs, and cheese from four different artisanal dairy plants in Slovakia. Among the 136 isolates of enterococci, 9 species of genus Enterococci (E. faecalis, E. faecium, E. durans, E. devriesi, E. hirae, E. italicus, E. casseliflavus, E. malodoratus, and E. gallinarum) were identified and were tested for their antimicrobial resistance (AMR) to 8 antibiotics (amoxicillin, penicillin, ampicillin, erythromycin, levofloxacin, vancomycin, rifampicin, and tetracycline); most of them were resistant to rifampicin (35.3%), ampicillin (22.8%), and tetracycline (19.9%). A PCR analysis of vanA (4.41%) and tetM (14.71%) revealed that antimicrobial resistance genes were present in not only phenotypic resistant isolates of enterococci but also susceptible isolates. The investigation of antimicrobial resistance in enterococci during the cheesemaking process can be a source of valuable information for public health in the concept of “One Health”.

Lactobacillus johnsonii and Lactobacillus zeae are among the lactobacilli with probiotic properties, which occur in sour milk products, cheeses, and to a lesser extent in raw milk. Recently, resistant strains have been detected in various species of lactobacilli. The aim of the study was to determine the incidence of resistant Lactobacillus johnsonii and Lactobacillus zeae strains in various types of raw milk. A total of 245 isolates were identified by matrix-assisted laser desorption/ionization mass spectrometry and polymerase chain reaction methods as Lactobacillus sp., of which 23 isolates of Lactobacillus johnsonii and 18 isolates of Lactobacillus zeae were confirmed. Determination of susceptibility to selected antibiotics was performed using the E-test and broth dilution method, where 7.3% of lactobacilli strains were evaluated as ampicillin-resistant, 14.7% of isolates as erythromycin-resistant, and 4.9% of isolates as clindamycin-resistant. The genus Lactobacillus johnsonii had the highest resistance to erythromycin (34.8%), similar to Lactobacillus zeae (33.3%). Of the 41 isolates, the presence of the gene was confirmed in five Lactobacillus johnsonii strains and in two strains of Lactobacillus zeae. The presence of resistant strains of Lactobacillus johnsonii and Lactobacillus zeae is a potential risk in terms of spreading antimicrobial resistance through the food chain.

Background: Freezing and thawing methods are critical to the final quality of food products. Methods: Our work focuses on evaluating the effect of five thawing protocols (in the refrigerator, at room temperature, in the microwave, and in a water bath at water temperatures of 20 and 40 °C) on the physicochemical properties, color, sensory properties, content of bioactive compounds, and antioxidant activity in frozen fruits of Fragaria spp. from different retail chains (n = 7) and from diverse countries of origin. Results: We found that although thawing at room temperature is a slow process, it best preserved the original quality of the strawberries when compared with other methods. Different thawing protocols had various effects on the color, sensory properties, polyphenol profile (TPC, TFC, TPA, and anthocyanins determined spectrophotometrically), and antioxidant activity (DPPH method) of strawberries. Our results indicate that each evaluated thawing method was viable. Conclusions: This study can provide a basis for selecting appropriate thawing processes in the strawberry processing industry based on the intended use of the food for further processing.