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  • Antioxidant capacity, C-vitamin and anthocyanils content in the fruits of elderberry (Sambucus nigra L.) types
    77-79.
    Views:
    181

    : Elderberry used to be a common medicinal plant since long. Its ripe fruit and inflorescence has been collected. Cultivation however, started in Hungary recently, with the early 90-es. Initially, has been planted, the 'Haschberg' cultivar. Our Department started first with the selection of favourable genotypes in the Hungarian spontaneous populations of the species, we aimed to find clones, which are earlier ripening than 'Haschberg', moreover, superior in any of the agronomical or quality traits. Present study deals with 19 new selected clones by their content of vitamin-C, anthocyanins and their antioxidant capacity. Environmental stresses are inducing, increased, accumulation of free radicals in living organisms. To evoid the harmful effects of the free radicals, we need to consume antioxidant compounds (flavonoids, anthocyanins, vitamins, etc.) In the literature there are quite a few references related to the anthocyanins and antioxidants of the elderberry. Measurements prove that substantial differences exist among the population of the species as for the content and quality of those compounds. In anthocyanin content, the difference between the highest and lowest values was 3000 mg/I, whereas in antioxidant content this value was 6001.1M. Those types, which contained less anthocyanin (<5000 mg/I), produced lower antioxidant capacity, whereas the highest anthocyanin content was associated with the strongest antioxidant activity. C-vitamin content varied between 36.5 and 96.4 mg/100g. These values provide daily human requirements by their consumption. Summing up all parameters, examined the best type was Cinkota 1.

  • Effect of variety and cultivation technology on phenols and antioxidant activity of sweet and sour cherry
    59-61.
    Views:
    418

    The goal of the present work was to compare different sweet and sour cherry cultivars and cultivation methods (bio/integrated) with respect to polyphenol content and antioxidant activity. The concentration of total polyphenols ranged between 880–1050 mg kg-1 of fresh fruit, whereas antioxidant activity expressed as TEAC was found to be between 5.4 and 10.3 mmol kg-1 for the sweet cherry cultivars examined. In case of sour cherry the level of polyphenols ranged between 1283 and 3490 mg/kg fresh edible part of the fruit. Antioxidant activity was recorded between 15–32 mmol kg-1 for the different sour cherry cultivars included in this work. After one-month storage at low temperature, the total phenols and antioxidant activity decreased by 2–40% in the sour cherry cultivars studied. The anthocyanin content in cherry cultivars was less (131–312 mg kg-1) than the135–1893 mg kg-1 found in sour cherries. Anthocyanin level was higher in samples produced under organic farming conditions than in those produced with integrated cultivation.

  • Antioxidant capacity, total phenolics and mineral element contents in fruits of Hungarian sour cherry cultivars
    59-64.
    Views:
    483

    Several epidemiological studies revealed that the consumption of antioxidant compounds and the risk of atherosclerosis, increased blood pressure or cancer are inversely proportional. Fruits of sour cherry contain a wide range of antioxidant compounds including melatonin, perillyl alcohol, ellagic acid, several flavonoids, polyphenolics, and anthocyanins. This study was carried out to survey the antioxidant power and mineral element content of seven commercial sour cherry cultivars and three cultivar candidates and to assess the influence of some external conditions on fruits' functional properties. Our analysis revealed nearly 5- and 2-fold differences between the lowest and highest antioxidant capacities and total phenolics content, respectively. Some cultivars (`Kántorjánosi' and ‘Újfehértói fürtös') and cultivar candidates (D, 'Petri' and 'Éva') showed outstanding antioxidant capacity and total phenolic content; in addition, mineral element content in fruits of the ‘Újfehértói fürtös' cultivar was also favourable. Redox parameters of fruits were influenced by the cultivation plot or fruit positions within the canopy in about half of the cultivars tested. Genetic background of cultivars forms the decisive factor in determining fruits' antioxidant capacity, although external factors may have also sizeable modifying effects. Enhanced functional properties of the fruit may also be further increased through breeding programs since considerable variation exists within the tested germplasm.

  • Concentration of ‘Oblachinska’ sour cherry juice using osmotic distillation
    31-34.
    Views:
    258

    Sour cherry is one of the most famous and characteristic Hungarian fruit what is also commonly used in food production as a colour additive. The sour cherry cultivar, ‘Oblachinska’ was shown to be a rich source of antioxidant compounds, including mainly anthocyanins. Valuable compounds in fruit juice – vitamins, polyphyenols etc. –are heat-sensitive molecules, which should be taken into account during the process of concentration to prevent degradation. Osmotic distillation seems a suitable option to product high quality sour cherry juice because this process does not require high temperature or pressure. Raw juice with approximately 15°Brix was used for the experiment and tried to concentrate up to 60° Brix where the water activity low enough to inhibit the microbiological deterioration. Before and after the process, TPC (total phenolic compounds) and FRAP (ferric reducing antioxidant power) was measured using spectrophotometric methods to determine the effect of the osmotic distillation. Our results point out that osmotic distillation is a promising method to concentrate sour cherry juice and prevent the loss of valuable compounds.