Method for evaluating freshness of Keemun black tea based on volatile component content

Abstract

The invention provides a method for evaluating freshness of Keemun black tea based on volatile component content. The method comprises the following steps: (1) taking Keemun tea leaves or tea soup, and extracting volatile components by using an organic solvent; (2) removing extracted non-volatile components, concentrating and feeding a sample; (3) carrying out data acquisition on the volatile components, and quantifying geraniol, methyl salicylate, linalool, dihydrosea anemone lactone and rye lactide; and (4) calculating the ratio of the total amount of geraniol, methyl salicylate and linalool to the total amount of dihydrosea anemone lactone and rye lactide, and taking the ratio as a fresh degree value; when the freshness degree value is greater than 4, indicating that the sample is fresh Qihong; when the freshness degree value is 1-4, indicating that the sample is cured Qihong; and when the freshness value is less than 1, indicating that the sample is the aged Qihong tea. The method for objectively evaluating the freshness of the Keemun black tea is provided for the first time, the blank in the field is filled, and a basis is provided for evaluating the freshness of other black tea and oolong tea.

Description

technical field [0001] The invention relates to the field of tea quality chemistry, in particular to a method for evaluating the freshness of Keemun black tea based on the content of volatile components. Background technique [0002] Qi Hong, because of its characteristic and high aroma, makes it one of the three most fragrant black teas in the world, along with Sri Lankan Uva black tea and Indian Darjeeling black tea. Qihong is a black tea made from the fresh leaves of tea tree varieties mainly based on the Qimen County of Anhui Province as the core production area and the clonal improved varieties selected and bred from them. The characteristic aroma of Qihong is generally described as "Qimen fragrance", which is an important quality characteristic. [0003] Black tea, like oolong tea, white tea, and dark tea, is a kind of tea that can be stored properly. Its aroma will also change significantly during storage. In recent years, it has also been loved and even praised by s...

AI Technical Summary

Problems solved by technology

In contrast, little research has been done on the volatile components or aroma of Qihong or black tea during storage and has not received widespread attention

In addition, at present, the freshness of Qihong is almost completely relied on sensory evaluation, which is subjective, and there is no method to objectively evaluate the freshness of Qihong.

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