The microbiological quality of dairy products from small-scale producers in Serbia was analysed. A total of 302 dairy products [raw (n = 111) and pasteurized milk cheeses (n = 79) and kajmak (n = 112)], were collected and tested for the presence of pathogens, Listeria monocytogenes and Salmonella spp., and enumerated for Coagulase-positive staphylococci (CPS), Escherichia coli, and yeasts and moulds. None of the samples tested positive for Salmonella spp., while L. monocytogenes was recovered from one raw milk cheese and five kajmak samples. Raw milk cheese and kajmak also had higher levels of indicator microorganisms, namely E. coli and yeast and moulds. Molecular serotyping grouped L. monocytogenes isolates into serogroups 1 (1/2a and 3a) and 3 (1/2b, 3b, and 7). When exposed to eight antibiotics, L. monocytogenes isolates were mostly sensitive, with the exception of oxacillin and reduced susceptibility to clindamycin, penicillin G, and trimethoprim/sulfamethoxazole, emphasizing the importance of continuous surveillance for antimicrobial resistance. Samples that tested positive for Listeria spp. also had higher loads of indicator microorganisms, namely E. coli and yeast and moulds, suggesting lapses in hygiene practices during production. Collectively, these data emphasize the need for improved food safety and hygiene practices among small-scale dairy producers. This is crucial to reduce the microbial contamination and improve both the quality and safety of dairy products in the Serbian market.

The main aim of this study was to analyze hygiene practices in small-scale dairy plants (SSDPs) in Serbia. A total of 60 plants were included in the research. A survey questionnaire used for SSDPs was designed to obtain the main information about hygiene practices they perform, as well as the data about the SSDPs, their production portfolio, and improvement plans. For the purpose of this study, a good hygiene practice score (GHPS) was calculated showing that the average score is 75%, spanning from 71.4% to 80.3% depending on the type of dairy plant. This study showed that the biggest challenges for small-scale dairy plants are associated with adequate labeling and external analysis of their dairy products, followed by record keeping and use of appropriate food contact materials. As expected, registered and approved SSDPs had higher GHPS scores and more information on their labels than those still in the approval or registration process. This study confirms the need for supporting this type of dairy producer to improve two main pillars of their business—the infrastructure for where they produce dairy products and awareness/knowledge of food safety legislative requirements. At the same time, approved processors are significantly underutilizing their processing capacity, which implies the need for both policy change consideration and educational initiatives. The policy changes should aim to align regulations with small-scale dairy processing realities.

Kajmak, a traditional Serbian dairy product, is a top, crust layer of milk containing a high amount of aggregated milk fat and proteins, formed during long cooling of boiled milk. Due to variations in production technologies, environmental conditions, and the composition of raw milk which varies from region to region, the quality of kajmak produced traditionally in households is very inconsistent. Attempts to produce kajmak in the industry environment (dairy plants) turned out to be highly challenging in terms of achieving a uniform quality and safety of the product. In order to have a deeper insight into the quality of kajmak produced by the traditional manufacture and the industry, the main objective of the study was to investigate sensorial, physicochemical, and textural properties of kajmak produced in households and dairy plants and distributed through open markets and retail stores, respectively. A total of 36 samples of kajmak were analyzed for thirteen quality characteristics. The results obtained showed a high variability in kajmak quality. The study applied a mathematical calculation of a single total quality index (TQI) that makes all quality attributes comparable. Based on the obtained results, it was determined that kajmak produced in households had a better TQI, which leads to the conclusion that in terms of kajmak quality, the traditional production method is still superior to the industrial one. The correlation between the examined quality characteristics was investigated using Pearsons bivariate correlation analysis and principal component analysis (PCA). By applying PCA, four principal components highlighting the most important quality characteristics were extracted. The results of the study suggest that further research on the quality of this valuable dairy product, as well as government support and investment in the small scale dairy sector, could be beneficial.

The first food in neonatal puppies is milk. Along other functions as nutritive and purgative, colostrum serves as the induction route for the enteral microbiome. As one of the two most abundant bacteria groups in the colostrum, the lactic acid bacteria are a significant factor due to their attributed functional properties in the digestive system of neonates. Dog lactational microbiome has not been studied in detail and therefore the aim of this work was to isolate, characterize lactobacilli bacteria from canine milk and estimate their antibacterial properties and ability for survival at different temperatures. Four lactic acid bacteria isolates were identified by MALDI TOF and confirmed by 16s sequencing. All four successfully unambiguously identified isolates showed survival at both storage regimes with the best growth at 37 °C in bile salt supplemented medium. The growth of S. aureus was impaired by three of four isolates and E. coli by two. The obtained results provide a promising base for further probiotic analysis of isolates in both puppies and lactating female dogs.

Cleaning and disinfection are essential hygiene measures in the food industry, aimed at ensuring food safety and preventing contamination of both the production environment and finished products. In the dairy industry, these measures are especially important in cheese production, as the physical and chemical properties of cheese can provide a favourable environment for the growth of pathogenic microorganisms. Among these, Listeria monocytogenes is particularly significant due to its ability to survive under adverse conditions, including low temperatures, a wide range of pH values, and high salt concentrations. Furthermore, its ability to form biofilms allows this pathogen to persist long-term in the production environment and increases its resistance to disinfectants. The paper highlights the importance of cleaning and disinfection as key measures to control L. monocytogenes in cheese production, with particular reference to sources and routes of contamination, survival in the production environment, biofilm formation, and the specificities of traditional cheese production. The results show that effective control of this pathogen requires an integrated approach, including properly conducted cleaning, appropriate disinfection, and continuous monitoring of hygiene in the production environment. Consistent application of these measures significantly reduces the risk of contamination and improves cheese safety.

Yogurt starter cultures, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus, are essential for the development of the characteristic texture, flavor, and nutritional properties of fermented milk. Their activity depends on a stable microbiological environment, while in industrial practice equipment hygiene is maintained through the use of various disinfectants. However, residues of these chemicals, if left on surfaces after insufficient rinsing, may exert an inhibitory effect on beneficial bacteria. Oxidizing agents, quaternary ammonium compounds, and chlorine-based disinfectants are particularly notable as potential factors that slow down milk acidification, reduce lactic acid production, and lead to variations in the sensory attributes of yogurt. A review of the available literature indicates that even low concentrations of residues can cause disturbances in fermentation kinetics, prolong fermentation time and affect the consistency of the final product's quality. These findings emphasize the importance of proper selection of disinfectants, as well as the need for validation of rinsing procedures in the dairy industry. Understanding the interaction between residues and starter cultures contributes both to the improvement of biosafety and to the preservation of technological efficiency in yogurt production.