Abstract
Thermal processes play an extremely important role in the formation of quality indicators of green tea. The main technological process is fixation, which can be carried out by various methods: roasting, steaming, hot air and electrophysical methods. Fixation is essential in green tea processing to inactivate the polyphenol oxidase enzyme. In Georgia, green tea is mainly made from local plant populations using the roasting method. Making green tea is an energy intensive process. The paper presents the results of research on the influence of fixation methods on quality, chemical and safety parameters of green tea. The results of the study of catechins in experimental green tea extracts by high-performance liquid chromatography (HPLC) showed that epigallocatechin gallate is equally present in green tea fixed by electromagnetic induction(Georgian patent 7427 B. 2022) and evaporation, and is superior to the product obtained by the roasting method. The antioxidant activity of tea extracts is in direct correlation with the total amount of polyphenols. According to the results of research, toxic elements: lead (Pb), arsenic (As), cadmium (Cd), mercury (Hg), copper (Cu), as well as: zinc (Zn), manganese (Mn), iron (Fe) absorption spectrometer (AAS 6 000), confirmed the high level of safety of Georgian tea in accordance with established standards.
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