COMPARATIVE ASSESSMENT OF THE CONTENT OF VITAMINS P AND C IN TEA EXTRACTS OF VARIOUS COMMERCIAL TEA BRANDS

Abstract

The article presents the results of a comparative analysis of the content of biologically active substances contained in tea, such as bioflavonoids with P-vitamin activity and vitamin C (ascorbic acid), which have powerful antioxidant, antitumor properties, etc. Determining the content of these biologically active substances in tea extracts allows draw conclusions about the quality of tea raw materials. The paper presents and analyzes the content of these biologically active substances in extracts of various types of tea: green and black of various brands, as well as the results of a correlation analysis of the ratio of the price category of selected brands of tea and the content of vitamins P, in terms of rutin, and C in them. Ten samples of green and ten samples of black tea of various brands were selected for the study, which were bought in trade establishments of the Sumy city. The data obtained during the study show that, on average, the content of biologically active substances such as vitamins P and C is about twice as high as in green tea compared to black tea. This fact can be explained by the fact that black tea undergoes a fermentation process, which has a significant impact not only on the organoleptic characteristics of tea, but also on biochemical parameters, including the content of vitamins P and C. The active compounds showed that the most expensive studied samples of green and black tea, the price of which exceeded one hundred hryvnia, had lower levels of vitamins P and C in them compared to other, cheaper samples. Low values of the content of the studied biologically active substances in tea may be the result of inadequate quality of the tea raw material itself or non-compliance with the technology of its processing or storage of finished products.