Search Results (3)

The jostaberry (Ribes × nidigrolaria) hybrid is a rich source of phytochemicals with high antioxidant activity (AA). However, due to the thick skin and seeds, the whole fruits are rejected by some consumers, and their incorporation into food products may negatively affect the sensory properties. Furthermore, after drying, including freeze-drying, jostaberries become sticky and gummy, making them unsuitable for grinding into powder. In this context, the present study aims to improve the handling properties and evaluate the biological value, antioxidant potential, physicochemical characteristics, and color parameters of biopolymer microparticles enriched with biologically active compounds (BACs) from jostaberry during freeze-drying and subsequent storage in the dark under ambient conditions (22 ± 1 °C, relative humidity ≤ 75%). For this, jostaberry extract (JE) was encapsulated using combinations of biocompatible carriers: maltodextrin-nutriose (resistant dextrin)-pectin and maltodextrin-nutriose-sodium alginate. The encapsulated products were freeze-dried to obtain microparticles (MNPJ and MNAJ) with yields of 87.7% and 88.9%, respectively. It was found that the biopolymer matrix provided superior protection for the encapsulated BACs during freeze-drying compared to the fruit matrix. The AA determined in MNPJ and MNAJ microparticles by DPPH and ABTS assays decreased only 1.1 and 1.5 times, respectively, while in freeze-dried jostaberry, AA showed a decrease of 3.7 times (DPPH) and 2.3 times (ABTS), respectively. Tukey’s post hoc HSD analysis revealed multiple significant differences (p < 0.05) between storage intervals for all measured parameters. While DPPH and ABTS values progressively decreased, total polyphenols (TPC) and anthocyanins concentration (TAC) and their retention efficiency showed changes after specific storage intervals (3, 6 and 12 months). After 12 months of storage, TPC and TAC decreased by 8.2% and 12.2% in MNPJ and by 3.3% and 3.9% in MNAJ, respectively. Therefore, microparticles containing sodium alginate showed the lowest BAC loss during storage. The obtained results reveal that after 12 months of storage, the color and physicochemical properties of the microparticles remained largely stable. Full article

Anthocyanins are the most important polyphenolic substances contained in blackcurrant fruits. They are responsible for the various health benefits caused, in particular, by their high antioxidant activity. Anthocyanins derived from anthocyanidins cyanidin and delphinidin are typical for blackcurrant fruits, especially their rutinoside and glucoside forms. These four anthocyanins usually represent about 97–98% of total anthocyanins in blackcurrant fruits. In this study, we developed and validated a new HPLC-DAD method for rapid anthocyanin separation and determination in fifteen perspective blackcurrant cultivars (‘Ruben’, ‘Ben Lomond’, ‘Ben Conan’, ‘Ceres’, ‘Moravia’, ‘Ometa’, ‘Lota’, ‘Fokus’, ‘Tenah’, ‘Sejanec’, ‘Consort’, ‘Triton’, ‘Ben Hope’, ‘Ben Gairn’, and one gooseberry hybrid ‘Josta’). Eight of them were monitored throughout the three-year experiment. The most represented anthocyanins in all monitored blackcurrant cultivars were delphinidin-3-rutinoside (36.7–63.6%), cyanidin-3-rutinoside (26.4–40.6%), delphinidin-3-glucoside (6.1–17.9%), and cyanidin-3-glucoside (1.3–9.9%). The individual anthocyanin proportion (%) in each cultivar was specific, and a similar profile was verified in a three-year period for eight available cultivars. Total anthocyanin content expressed as a sum of four major anthocyanins present in blackcurrants was compared with values expressed as the equivalent of cyanidin-3-glucoside, as many authors do. We revealed an underestimation of about 20% with the latter method. Cultivars with the highest average total anthocyanin content were ‘Ben Gairn’ (294.38 mg/100 g), ‘Ceres’ (281.31 mg/100 g), and ‘Ometa’ (269.09 mg/100 g). Full article