This research project aimed to investigate the physico-chemical, sensory, hygienic and safety characteristics of raw goat milk, whey, brine and traditional goat cheese during the ripening period of 28 days. Physico-chemical parameters included the determination of dry matter, fat, ash, protein, pH, water activity and NaCl content. The presence of Enterobacteriaceae and fungi was estimated on milk and cheese samples, and a sensory panel evaluated the products’ features and acceptability during ripening. The results show that the cheese under study belongs to the acid full-fat cheese group. A consumer panel attributed high scores to the goat cheese, until the 21st day of ripening. After this period, the overall features altered significantly, including augmented bitterness, odor intensification and the development of molds on the surface. The presence of fungi, associated with Enterobacteriaceae, suggests that the hygiene of the production processes needs to be improved. Regarding microbial safety, the detection of putative pathogens and antibiotic resistances recommend an active surveillance of traditional foods to avoid foodborne infections and/or the dissemination of resistant microorganisms along the food chain.

In this study, an Artificial Neural Network (ANN) model is used to solve the complex task of producing fresh cheese with the desired quality parameters. The study focuses on kombucha fresh cheese samples fortified with ground wild thyme, supercritical fluid extract of wild thyme, ground sage and supercritical fluid extract of sage and optimizes the parameters of chemical composition, antioxidant potential and microbiological profile. The ANN models demonstrate robust generalization capabilities and accurately predict the observed results based on the input parameters. The optimal neural network model (MLP 6-10-16) with 10 neurons provides high r2 values (0.993 for training, 0.992 for testing, and 0.992 for validation cycles). The ANN model identified the optimal sample, a supercritical fluid extract of sage, on the 20th day of storage, showcasing specific favorable process parameters. These parameters encompass dry matter, fat, ash, proteins, water activity, pH, antioxidant potential (TP, DPPH, ABTS, FRAP), and microbiological profile. These findings offer valuable insights into producing fresh cheese efficiently with the desired quality attributes. Moreover, they highlight the effectiveness of the ANN model in optimizing diverse parameters for enhanced product development in the dairy industry.

This study investigated the effect of a concentrated kombucha inoculum and transglutaminase (TG) on the rheological and textural properties of fermented milk products and compared their average production costs to commercial yoghurt. Semi-skimmed milk was used, to which microbial TG was added at a level of 0.02% w/w. The kombucha inoculum, prepared from black tea, was concentrated to 55.6% total solids. Four samples were produced: two with TG and two without. The TG-containing samples showed significantly higher textural properties, including firmness and consistency, than the non-TG samples. They also exhibited the largest hysteresis loop area and the highest yield stress, indicating a stronger gel structure. The Herschel–Bulkley model successfully described the flow behaviour of all samples and confirmed their shear-thinning, non-Newtonian nature. Principal Component Analysis (PCA) showed that both TG addition and inoculum concentration significantly influenced the product properties. TG improved the rheological and textural properties and increased the stability during storage. However, the production costs for TG-treated samples were higher than those for non-TG-treated samples and commercial yoghurt. Nevertheless, the higher costs could be justified by the perceived additional nutritional benefits for consumers. Overall, the results show that the combination of concentrated kombucha inoculum with transglutaminase can improve the structural and rheological quality of fermented dairy products, which is potentially of commercial importance.

Fresh cheese is characterized by a limited shelf life, which represents a major challenge in its production. Wild thyme (Thymus serpyllum L.) has an antimicrobial capacity demonstrated in numerous studies. The utilisation of its by-product obtained in the production of filter tea could improve fresh cheese technology by obtaining a product with additional functional value and protecting the environment by reducing industrial waste. Our study sought to explore how incorporating wild thyme, in the form of dry extract, supercritical fluid extract, and herbal ground, affects the microbiological composition of fresh cheese made with kombucha inoculum as the starter culture over a 30-day storage period. To assess antimicrobial efficacy, we deliberately exposed the samples we produced to common foodborne pathogens, namely Listeria monocytogenes and Staphylococcus aureus. The results showed that the total number of L. monocytogenes and S. aureus in each sample (produced with dry extract, supercritical fluid extract, and herbal ground) decreased significantly during the storage period. The decrease in L. monocytogenes count varied from 0.6 to 1.7 log CFU/g. The results suggest that a by-product from the production of wild thyme filter tea is suitable for the production of fresh cheese to improve its antimicrobial properties against L. monocytogenes and S. aureus.