Abstract
The physicochemical, microbiological and technological stability indicators of katyk enriched with molecular hydrogen were investigated in this study. The research objects included control katyk, katyk treated with molecular hydrogen, katyk enriched with functional additives, and samples where molecular hydrogen and functional components were applied together. Molecular hydrogen was introduced into the product by bubbling H ₂ gas with a purity of 99.99% at a flow rate of 0.5–1.0 L/min for 7 minutes at 4–10 °C. During storage, active acidity (pH), water activity, oxidation–reduction potential (ORP), color parameters and microbiological indicators were determined. The obtained results showed that the combined application of molecular hydrogen and functional additives slowed down the acidification process of the product and contributed to maintaining pH stability. At the end of storage, the pH value of the control sample decreased to 3.52, while in the combined treatment sample it remained at 4.13. Water activity results indicated stabilization of the moisture state. ORP analysis demonstrated the formation of a reducing environment in H ₂ -treated samples: the values were recorded in the negative range (approximately from −150 to −350 mV), unlike the control samples with positive ORP values, indicating a decrease in the intensity of oxidative processes. Microbiological analysis showed that the combined treatment reduced the amount of Enterobacteriaceae, yeasts and molds while maintaining lactic acid bacteria. In this sample, Enterobacteriaceae reached 5.90±0.95 log ₁₀ CFU/g, yeasts and molds were 6.10±0.30 log ₁₀ CFU/g, and lactic acid bacteria were maintained at 6.65±0.20 log ₁₀ CFU/g. The results confirm that the combination of molecular hydrogen bubbling and functional additives is a promising approach for improving the storage stability and quality characteristics of katyk.