Microbiological changes in craft hard cheeses from raw goat milk during ripening with the use of mites Acarus siro

The nutritional and biological values of craft hard cheeses made from raw goat milk, in combination with their unique flavor characteristics, increase consumer demand and expand their range on the market. Production of such cheeses is concentrated on small farms and is becoming increasingly common in Ukraine. Ripening of such hard cheeses made from raw goat milk is provided by a significant species diversity of their biome, particularly bacteria, molds, yeasts, and mites, which requires a quality and safety assessment of such cheeses at different ripening periods. Microbiological indicators of Alpine and Yoghurt hard cheeses made from raw goat milk were determined during the study. A study was carried out using traditional methods of microbial analysis, as well as MALDI-TOF technology. Alpine cheese was characterized by relative stability in QMAFAnM at 7 days, 6, and 12 months. In Alpine cheese, the maximum amount of yeast was detected at 7 days of age, and the maximum amount of moulds was detected at 6 months of ripening. Lactic acid bacteria, in particular, Lactococcus lactis and Lactobacillus plantarum, formed the microbiome basis of Alpine cheese during all ripening periods. Staphylococcus simulans, S. equorum, Enterococcus faecalis, E. durans, Escherichia coli and Bacillus cereus were isolated in small amounts from Alpine cheese. The number of QMAFAnM in Yoghurt cheese increased throughout the ripening period, while the number of yeasts and moulds reached a maximum at 6 months. Lactic acid bacteria, in particular, Lactococcus lactis and Lactobacillus paracasei, dominated at all ripening periods of Yoghurt cheese (7 days, 6 and 18 months). Staphylococcus equorum, Enterococcus faecalis, Escherichia coli, Raoultella ornithinolytica, Providencia stuartii, and Kurthia gibsonii were isolated in small amounts from Yoghurt cheese. Alpine and Yoghurt hard cheeses made from raw goat milk are ripened with mycoid mites Acarus siro, which are involved in forming the cheese rind. The study results can be used as an element of the authenticity criterion for craft hard cheeses made from raw milk.