Changes of Components Affecting Color, Aroma and Taste during the Processing of Anxi Tieguanyin

The effects of different processing procedures on the aroma and quality components of Anxi Tieguanyin were studied, to provide a certain scientific basis for improving further development of Tieguanyin. In this study, Tieguanyin was processed according to the production process of Anxi Tieguanyin. The changes of aroma components, tea polyphenols, caffeine, free amino acids, flavonoids, tea pigments and other important internal components of Tieguanyin were investigated. Significant differences of the component contents were observed in different processing stages. The content of tea polyphenols and caffeine showed an overall downward trend. The content of tea polyphenols and caffeine were decreased by 68.52% and 47.74% during the entire processing process, while the content of amino acids and flavonoids showed an overall upward trend. The amino acids content during the entire processing process was increased by 59.67% and the flavonoids content was increased by 1.62 times. The content of tea pigments showed no obvious changes. Among them, the Shaqing process had the greatest impact on the color and fragrance components of Tieguanyin during the processing. After the Shaqing process, the content of tea polyphenols was decreased by 40.66%, and the content of flavonoids significantly was increased to 6.93 mg/g, which was the key processing node. In addition, Shaiqing, Yaoqing and Liangqing were also important processes that affected the aroma and quality of Tieguanyin. This article provided scientific basis for the quality improvement and process optimization of Anxi Tieguanyin.