文章基本信息

标题：Authenticity evaluation of tea-based products
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作者：Čížková H. ; Voldřich M. ; Mlejnecká J. 等
期刊名称：Czech Journal of Food Sciences
印刷版ISSN：1212-1800
电子版ISSN：1805-9317
出版年度：2008
卷号：26
期号：4
页码：259-267
DOI：10.17221/10/2008-CJFS
出版社：Czech Academy of Agricultural Sciences
摘要：This study proposes a method for estimating the content of tea in tea-based products. Broadly, this methodology is based on selecting chemical markers of the quality and authenticity of tea (and, therefore, of tea-based products), optimising the relevant analytical methods, and determining variations (type, origin, quality) among samples of green and black leaf teas. The contents of the selected markers (theobromine, caffeine, theanine, and total polyphenols) in tea-based products (iced teas, instant teas) were determined. Then, the dry tea content in these products, expressed as the equivalent amount of dry tea leaves, was calculated on the basis of two sets of mean data for these analytes: average literature data, and the mean experimental data obtained with our samples of leaf tea. With regards to the latter, we propose to use of the following averages for caffeine, theobromine, theanine, and polyphenols: for 100 g of black tea-based products 1.9 g, 0.13 g, 1.3 g, and 9.1 g, respectively; for 100 g of green tea-based products 1.9 g, 0.16, 1.7 g, and 14.7 g, respectively. Using this method, we found that approximately one third of the analysed samples failed to meet the tea extract levels required by German and Austrian legislations, while about 10% did not comply with the less demanding Czech legislative requirements.
关键词：tea; tea-based products; authenticity; quality download PDF Impact factor (Web of Science – Thomson Reuters) 2017: 0.868 5-Year Impact Factor: 1.107