Influence of process parameters on (poly)phenol content during different blueberry leaf extraction procedures

Blueberry is a perennial, bushy plant that is extremely rich in phenolic components, which are significant for its antioxidant activity as "catchers" of radicals. The aim of this work is to examine the influence of process parameters during different blueberry leaf extraction procedures on the (poly)phenol content. As extraction techniques, maceration, mixing on a shaker and ultra-sound-assisted extraction were used as examples of clastic and modern types of extraction, and the process parameters that were monitored were the influence of the number of revolutions, etha-nol content in solvent, influence of time, pH value and plant material-to-solvent ratio (solid-to-solvent ratio). Ethanol was used as an extraction agent. The content of total (poly)phenolic com-pounds was determined using the Folin-Ciocalteu reagent, the flavonoid content using aluminum chloride, and the anthocyanin content using the pH differential method. The results of the work showed that the extraction of blueberry leaves is significantly influenced by process variables, as well as that higher quality extracts are obtained by ultrasound-assisted extraction.