Determination of the type of solvent in the technology of production of tea extracts with antioxidant activity

Abstract

The aim of the study was to determine the type of solvent that allows the most complete extraction of antioxidant substances from white, black and green tea (Camellia sinensis). The objects of the study were extracts of three types of tea obtained using various solvents: water, a mixture of water-ethanol (75% vol./25% vol.), A mixture of water-ethanol (50% vol./50% vol.), A mixture of water -ethanol (25% vol./75% vol.) and ethanol (96%). In extracts of white, black and green tea, the total content of phenolic substances, flavonoids, antiradical activity by the DPPH method, and the restoring force by the FRAP method were determined. The maximum values of the total content of phenolic substances were found in the extract of white tea based on ethanol and a water-ethanol solvent system (50/50), black tea when extracted with water, green tea with a water-ethanol solvent ratio (50/50). High values of the total content of flavonoids were established for white tea extract based on a water-ethanol solvent system (50/50), black tea when extracted with water, green tea, when using ethanol as a solvent. Low antiradical activity was found in white tea extract based on a water-ethanol solvent system (50/50), in ethanol-based black tea, and green tea showed low values when extracted with water. The highest index of restorative power was found in white tea extract based on a water-ethanol solvent system (25/75), in black and green tea when extracted with water. Thus, as a result of the study of extracts of white, black and green tea, it was found that when the white tea is extracted with a water-ethanol (50/50) solvent system, the largest amount of antioxidant substances is extracted. The maximum amount of antioxidants from black and green tea is extracted using water as a solvent.