Purpose – The purpose of this paper was to determine total polyphenols (TP), total flavonoids (TF) and (-)-epigallocatechin gallate (EGCG) in five commercial tea extracts and in their infusions at various temperatures (95-60°C) and brewing times (5-30 min). Design/methodology/approach – TP was determined by the Folin–Ciocalteu method, TF by the aluminium chloride colorimetric method and EGCG by HPLC method. Findings – The results showed that White tea – Silver needle had the highest content of TP and EGCG when extracted, but its infusions had very poor concentrations of these compounds. Green tea infusion was better source of TP and EGCG than white or black tea, although its extract did not contain a very high amount of TP compared to the latter two types. Black tea extract had a relatively high content of TP and TF in its extract. Its infusions as well contained higher concentrations of TP than white tea, but lower concentrations of EGCG than all studied teas. Originality/value – Increasing infusion time and temperature does not necessarily increase the concentration, according to the results. To the authors’ knowledge, this is the first report on comparing these types of tea, especially the white tea, with other well-known teas under various infusion conditions. The extraction of the white tea leaves was also not found in previous works.

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Purpose There are many variations of brewing techniques which can impact both flavor and chemistry of the brew significantly. Therefore, the purpose of this study was to understand and identify the most common conditions used among a relatively large sample of worldwide tea consumers for preparing tea drinks. Design/methodology/approach An electronic questionnaire was formed via Google Drive© and distributed publicly online from 12 November 2014 to 9 January 2015. It contained 18 questions divided into sections. The valid answers received from 2,690 person were coded and statistically analyzed using SPSS 20.0 to calculate the frequencies, categorize the data into observed variables by using cross-tabulation and compare the observed data with the author expectations by using the chi-square test technique. Results were presented as (frequency; percent). Findings The results showed that a lot of tea-drinking respondents add sugar to their drink (2,242; 87.4 per cent). The great majority of respondents would drink their tea with additives (natural flavoring) (1,814; 70.7 per cent). Furthermore, there was a significant association between the number of tea drinkers and their gender and country of residence (p < 0.05), while the age of the respondents was not a significant factor affecting tea drinking. The same was observed about the association between number of people using additives and their gender, country of residence and age. Most of the participants thought that adding sugar would decrease tea’s health benefits, while adding some natural flavoring would increase it. Originality/value These most common conditions used among tea consumers can guide further conducted researches on tea drink to have more impact on people’s ways and understanding of different tea infusion preparations.