Effect of protective cultures on selected parameters of fresh cheese

Protective cultures are selected microorganisms that inhibit undesirable microbiota through metabolic activity, thereby improving the safety and shelf life of dairy products. This study evaluated the effect of protective cultures on the physicochemical, microbiological, and sensory properties of fresh cheese during 21 days of storage at 6–8 °C. Three variants were prepared: a control with the starter culture CHN-19 and two experimental samples containing FreshQ® Cheese 3 and FreshQ® 9 (Lacticaseibacillus rhamnosus). The application of protective cultures resulted in a slightly faster acidification but did not significantly affect dry matter or fat content. Microbiological analysis revealed higher counts of lactic acid bacteria and generally lower counts of psychrotrophic microorganisms in samples containing protective cultures on several storage days, while Escherichia coli and moulds were not detected. Sensory evaluation indicated that cheeses with protective cultures, particularly FreshQ® 9, maintained a pleasant flavour and appearance even after 21 days of storage, whereas the control sample became sensorially unacceptable after approximately two weeks. The application of protective cultures therefore enhances the sensory stability and microbial safety of fresh cheeses without adversely affecting their technological characteristics.