MICROBIOLOGICAL QUALITY AND REGULATORY SAFETY ASSESSMENT OF FRESH CHEESE ENRICHED WITH MINT AND THYME
Keywords:
fresh cheese, Mentha piperita, Thymus vulgaris, lactic acid bacteria, yeasts and moulds, food safetyAbstract
This study evaluated the microbiological quality and regulatory safety of fresh cow’s-milk cheese produced without herbs (control) and with mint (Mentha piperita L.) or thyme (Thymus vulgaris L.) during 20 days of storage. Lactic acid bacteria (LAB), Escherichia coli, Staphylococcus aureus, Bacillus cereus, yeasts and moulds, anaerobic bacteria and Enterobacteriaceae were enumerated, while Salmonella spp. was assessed qualitatively. Analyses were performed on days 1, 7, 12 and 20, generally in duplicate. Initial LAB counts were higher in the mint and thyme cheeses (5.26 and 4.99 log10 CFU/g, respectively) than in the control (3.74 log10 CFU/g). LAB decreased to day 12 in both herb-enriched cheeses and partially recovered by day 20, whereas the control showed a transient increase on day 12. Yeasts and moulds increased markedly on day 7 in all variants, reaching 4.33, 4.48 and 5.08 log10 CFU/g in control, mint and thyme cheese, respectively, followed by lower counts on days 12 and 20. E. coli, anaerobes and Salmonella spp. were not detected throughout storage. Low, sporadic counts of S. aureus and B. cereus were observed, and Enterobacteriaceae were restricted to early storage. The results were below the relevant numerical limits of the national microbiological criteria for Salmonella and coagulase-positive staphylococci. However, because analytical duplicates from one production batch do not constitute the statutory sampling plan, the findings support an indicative safety assessment rather than a formal declaration of legal conformity. Herb addition modified microbial succession but did not uniformly suppress LAB or yeasts and moulds
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