Chokeberry Pomace Utilization for Improving Selected Quality Parameters of Green Tea Leaves or Hibiscus Flower Infusions

Abstract

The utilization of food industrial by-products, especially pomace after juice processing, could be a big challenge. Chokeberry pomace is a valuable source of phenolic compounds, including procyanidins and anthocyanins. These compounds have, e.g., antioxidant, anticancer, hypoglycemic, hypotensive, hepatoprotective and cardioprotective effects. In this work, dried chokeberry pomace (2.0 g, 2.5 g and 3.0 g) was added to green tea leaves or white or red hibiscus flowers (0.5 g of each) to obtain mixtures for preparing infusions. Such products could be a valuable source of bioactive compounds. After brewing and cooling, selected quality parameters of the obtained infusions were tested: pH, total phenolic content (TPC), anthocyanin content and the instrumentally and sensorily determined color. The composition of the infusion had an impact on the color. Those from a mixture of chokeberry by-products and hibiscus possessed lower L* and higher a* and b* values than those composed of chokeberry and green tea leaves. Infusions prepared from the mixture containing dried chokeberry pomace (3.0 g) and green tea leaves (0.5 g) had a higher content of anthocyanins (17%) and phenols (48%), respectively, than other samples with the same proportions of ingredients. According to PCA analysis, the highest content of the tested bioactive compounds was obtained in infusions of green tea leaves with the addition of chokeberry pomace.