Black fruits, especially blackberries and black currants, are highly appreciated by consumers due to their nutraceutical properties, which have reported health benefits. This study aimed to assess the fruit quality of the blackberry (cv. ‘Čačanska Bestrna’) and black currant (cv. ‘Čačanska Crna’) created at the Fruit Research Institute, Čačak (Republic of Serbia) by evaluating basic quality parameters (fruit weight, soluble solids), and content of primary (sugars and organic acids) and secondary (phenolic compounds) metabolites. Additionally, the study examined the quality of frozen and long-term frozen storage (6, 9, and 12 months). The results showed that ‘Čačanska Crna’ contained a high level of total soluble solids (15.23°Bx), sugars (93.06 mg g⁻¹), and a high index of sweetness (159.48) as well as a high content of acids (34.35 mg g⁻¹) in the fruit. Both species were found to contain forty-seven phenolic compounds, including phenolic acids, flavanols, and anthocyanins, analyzed using high performance liquid chromatography-mass spectrometry (HPLC-MS). ‘Čačanska Bestrna’ had the highest amounts of phenolic acids (66.85 mg 100 g⁻¹) and flavanols (53.99 mg 100 g⁻¹), whereas ‘Čačanska Crna’ showed the highest levels of flavonols (8.57 mg 100 g⁻¹) and anthocyanins (139.11 mg 100 g⁻¹). Furthermore, the study revealed that anthocyanins were the most abundant phenolic group in both blackberries and black currants, and their levels remained constant during frozen storage. The sugar content in both species remained unchanged, while the acid concentration increased over time in blackberries but remained consistent in black currants. Overall, the findings highlight the superior phenolic content, particularly anthocyanins, of the cultivars with black fruits selected in Serbia. These cultivars have great commercial potential for the fresh market and processing. Moreover, the study suggests that frozen storage is an effective method for preserving their quality and beneficial properties.

Autochthonous genotypes of fruit species are very important source of genetic variability and valuable material for breeding work. Fruit Research Institute-Cacak has a long tradition of studying autochthonous genotypes of temperate fruits sporadically spread and preserved in some localities in Serbia. Over 2005-2006, the following properties of nine autochthonous sour cherry genotypes grown in Feketic region were investigated: flowering and ripening time, pomological properties, biochemical composition of fruits and field resistance to causal agents of cherry diseases - cherry leaf spot (Blumeriella jaapii (Rehm.) v. Arx.), shot-hole (Clasterosporium carpophilum (L?v.) Aderh.) and brown rot (Monilinia laxa /Ader et Ruhl./ Honey ex Whetz.). The genotypes were tested for the presence of Prune dwarf virus and Prunus necrotic ring spot virus. In majority of genotypes fruits were large, with exceptional organoleptical properties, whereas ripening time was in the first ten or twenty days of June. The highest fruit weight was observed in F-1 genotype (8.1 g). The highest soluble solids and total sugars content were found in F- 4 genotype (17.60% and 14.25%, respectively). As for field resistance to causal agents of diseases and good pomo-technological properties, F-1, F-2, F-3, F-7 and F-8 genotypes were singled out.

During the two-year research, a comparative analysis of the contents of 24 major volatile compounds and sensory characteristics of the plum spirits produced by spontaneous alcoholic fermentation of the plum mashes with or without stones from cultivar Cacanska Rodna and its parent cultivars ? Stanley and Pozegaca were carried out. The plum spirits obtained from Cacanska Rodna cultivar contain lower amounts of methanol, 1-hexanol, ethyl acetate and acetaldehyde and higher amounts of 3-methyl-1-butanol and 2-phenylethanol than the spirits from its parent cultivars. Contents of 1-propanol, 1-butanol and hexanoic acid in the spirits obtained from Cacanska Rodna cultivar were lower than the contents in the spirits from Pozegaca and higher than those in the spirits obtained from Stanley. The sensory quality of plum spirits, in addition to the cultivar, has been significantly influenced by the presence of stones in the mash during processing of plums into spirits. In processing plums with stones, the best-graded plum spirit was from Pozegaca (17.88), whereas in processing without stones, the best was Cacanska Rodna spirit (17.78). The spirits obtained from Stanley cultivar had the lowest sensory grades regardless of the processing method.

The purpose of study was to identify polyphenolic compounds and antimicrobial properties in berries and leaves of black currant (Ribes nigrum L.). Black currant berries and leaves showed different characteristics. Berries had a higher levels of the studied parameters compared to leaves. Berry extracts contained 2.90 to 5.90 times more total phenolics, flavonoids, condensed tannins and gallotannins compared to leaf extracts, and total antioxidant activity was 5.82 times higher in berries than in leaves. The main flavonol found in our sample of black currant berries and leaves was quercetin, followed by myricetin, while kaempferol was present in very small amounts. The most abundant phenolic acid in berry extract was caffeic acid, while leaf extract was dominated by ferulic acid. Microbial properties of extracts were examined using eight selected indicator strains. The tested extracts showed strong antimicrobial activity, ranging from 55.82 to 199.21 mg mL-1. The results suggest that berries and leaves of black currant are a good source of polyphenolic compounds and have strong antimicrobial activity.