| Abstract [eng] |
After the production of blueberry juice, a large part of the by-products remain. These products are generally not used in a rational way and are often utilized. Such a waste of blueberry pomace determines the loss of large amounts of valuable nutrients. According to scientific studies, high amounts of nutrient fiber and biologically active compounds have been found in bilberry pomace. These compounds have a beneficial effect for human health. The aim of this work was to apply different extraction methods of bilberry (Vaccinium myrtillus L.) pomace and evaluate the main chemical composition properties of the obtained fractions and extracts using various in vitrо methods. In the course of the research, were tried to select the most active extracts of the bioactive compounds and to apply them to in vitro systems. Firstly, the dried pomace was ground to obtain 2, 1, and 0.5 mm particle size fractions. Then extracts were obtained from bilberries using traditional and modern extraction techniques such as multi-level supercritical carbon dioxide extraction, accelerated solvent extraction and maceration. Antioxidant potential of extracts and solid plant material was evaluated by 2,2-diphenyl-1picrylhydrazyl (DPPH•) radical2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS•+) scavenging and oxygen radical absorbance capacity (ORAC) assays, total phenolic content (TPC) was determined by Folin-Ciocalteu method. Solid fractions investigated by QUENCHER approach showed that solid fractions obtained after various extractions, still contain significant amounts of active compounds. Qualitative chemical compostion analysis of bilberry pomace extracts, triacylglcerols and quantative analysis of anthocyanins were performed by ultra performance liquid chromatography. The highest concentration of anthocyanins showed MAC H2O/EtOH (8:2) extract. This extract was further selected for encapsulation by spray-drying with three different matrices, and the efficiency of the encapsulation was monitored. By using maltodextrin as an encapsulating agent, maximum encapsulation efficacy was obtained. These matrixes were added to the ecological yogurt without additives and then samples were kept for 4 weeks, and anthocyanins content was monitored weekly. This study revealed that bilberry pomace is a great source of bioactive compounds that can be further utilized in nutrition to enrich other nutritional values or to produce various natural food supplements. |
