Polyphenolic and basic chemical composition of black chokeberry industrial by-products

The aim of the work was to examine basic and polyphenolic composition of chokeberry pomace fractions achieved as a result of industrial-scale processing of fruit into juice. As the result of sieving and pneumatic separation use two kinds of fractions were obtained: containing seeds and seedless ones. The content of dry substance, total dietary fibre (TDF), protein, fat, ash, macro- and micro-elements, saccharides, organic acids, polyphenols and amygdalin were determined in the fractions. The examined fractions differed in the size of particles which resulted from the presence of various morphologic parts of fruits, e.g. flesh, skins, seeds, leaf, stalks as well as their agglomerates. The carried out research indicates that pomaces constituting a waste material should be perviewed as non-homogeneous raw material. The processing of chokeberry pomace should include separation of seeds as valuable raw material rich in fat (13.9%), proteins (24%) and mineral compounds. Seedless fractions, in turn, characterised by particularly high content of TDF (∼75%), proanthocyanidins (12,000 mg/100 g) and anthocyanins (1200 mg/100 g) may be applied in production of polyphenolic extracts and/or dietary fibre preparations. Subsequent usage of pomace must take into account the presence of amygdalin, which is present in considerable quantities (120-180 mg/100 g of dry matter) in seed fractions. These quantities are a few times higher in comparison with seedless fractions. The obtained results were subjected to statistical analysis in which a cluster analysis method was applied in order to present differences between examined fractions.