Changes in quality indicators of minimally processed wrinkled rose (Rosa rugosa Thunb.) petals during storage

Rosa rugosa petals, which have long been used in traditional medicine due to their attractive flavor and presence of bioactive components, are also commonly applied to produce minimally processed and nonthermally treated products with the addition of sucrose. Therefore, to ensure safety and high value of such products during storage, it is crucial to investigate changes in quality indicators. The examined material was non-thermally treated and homogenized petals of wrinkled rose with sucrose concentrations of 50%, 60%, and 70%. Products were stored at 6°C and 21°C for 54 weeks in darkness. Throughout the storage, they were analyzed for microbiological contamination and changes in vitamin C content, color and pH stability. Over the storage period, in samples containing 60 and 70% sucrose, a gradual reduction was observed in the total bacteria count and the yeast and mold count. After the storage period, the value of pH decreased very slightly, while very distinct changes were observed in color parameters at 21°C. Vitamin C content decreased sharply during the first 18 days of storage at both temperatures.