Raspberry (Rubus idaeus L.) is a plant from the rose family and the most important berry-type fruit in our country. The most significant sorts of raspberries grown in Serbia are the red sorts, namely Willamette, Meeker, Gradina, Malling exploit and Skina. Raspberry fruit may be used either fresh or as a raw material in food industry, for the production of fruit juice, nectar, syrup, concentrate, dried and frozen fruit. The goal of this paper is to determine pH, titratable acidity (as citric acid), soluble solids, concentration of anthocyanins, vitamin C and total polyphenols, and to perform sensory analysis and microbiological quality control in both fresh and frozen fruit. pH value was measured with pH-meter. The concentration of acids was determined by the volumetric method, by titration with NaOH. The dry matter was measured by a refractometer. The concentration of anthocyanins was determined by the spectrophotometry method. The concentration of vitamin C was determined using the volumetric method. The concentration of polyphenol compounds was determined according to the Singleton method. The microbiological methods of detection and counting microorganisms were performed according to ISO standards. The results of this study have shown that both fresh and frozen raspberries are a good source of anthocyanins, indicating that their consumption is favorable for human health and that they may be useful in the production of functional food. The microbiological analyses have shown the absence of L. monocytogenes and Salmonella spp., while the concentration of Enterobacteriaceae and E. coli was below 10 cfu/g in both fresh and frozen raspberry fruit.

The aim of this study was to estimate the influence of biopolymer coatings based on chitosan and zein on the quality and storage stability of prunes (Prunus domestica L., cv. Stanley) over a one-year period coupled with modified atmosphere conditions (5% CO₂ + 95% N₂). Samples were analyzed at defined intervals (every 3 months) regarding physicochemical properties, antioxidative capacity, vitamin C content, phenolic profile, headspace gas composition, microbiological status and sensory characteristics. Biopolymer coatings, modified atmosphere, and temperature play key roles in controlling oxygen availability, which consequently affects all tested properties of prunes. Application of both types of coatings significantly improves product stability compared to uncoated samples, slows moisture loss, stabilizes pH, reduces degradation of vitamin C, phenolic compounds, and antioxidant activity, and improves microbiological safety. Chitosan exhibits more pronounced effects due to its antimicrobial and antioxidant properties, while zein primarily contributes to barrier characteristics. Gradual decline in quality, significantly slowed in coated samples, is additionally mitigated at low temperature (4 °C), which further inhibits chemical, oxidative, and microbiological changes compared to storage at 23 °C. Despite zein coating providing superior preservation of several physicochemical quality parameters, chitosan-coated prunes achieved higher sensory acceptance, demonstrating that improved physicochemical stability does not necessarily correspond to better consumer acceptability.