Influence of overpressure on microbiological properties and aroma components of semi-hard cheese during ripening in specially designed ripening chambers

The aim of this study was to investigate the impact of special ripening conditions on the cheese ripening process and the qualitative characteristics of the final product. The ripening chambers were specially designed to allow precise control of microclimatic conditions, including temperature, humidity, airflow, and most importantly, overpressure. Research methods included conducting microbiological analyses and Gas Chromatography/Mass Spectrometry (GC/MS) analysis of volatile components on cheese samples aged in a control and overpressure chamber over two months at 10-16 °C and 75-85 % relative humidity. The effect of ripening time (3.59-6.41 weeks, which is approximately 3 weeks and 4 days, and 6 weeks and 3 days, respectively) and overpressure (1.18- 3.31 mbar) was investigated by response surface methodology (RSM). The results showed that overpressure has successfully controlled bacterial and yeast growth during ripening time. Mould levels have shown different trends, with initial growth, followed by a decrease until the end of the ripening period. As for volatile compounds, the presence of 3,5 dihydroxydecanoic acid 1,5 lactone was found to be the most abundant aroma component found in cheese samples. It was concluded that the use of special ripening chambers with overpressure treatment could significantly enhance the microbial stability and aromatic profile of cheese, thereby improving its overall quality.