Abstract: In order to study the feasibility of mechanical production of Puer tea, solar-drying green tea was processed according to ‘mechanized standardized production line for solar-drying green tea’, and fermented by the numerical control fermentation system developed by Pu’er Tea Thoroughbred Farm. Samples were collected in each process during production. Methods like electronic nose, GC-MS, HPLC combined with sensory evaluation were applied to analyze the changes of the components and aroma substances during the mechanization production of solar-drying green tea, which could provide a reference for mechanized processing and industrial upgrading of Puer tea. The results show that the evaluation results of the batch samples met the national standards, and the mechanized production of Puer tea was feasible. In the process of the numerical control fermentation, the contents of catechins, GA, water extract, tea polyphenols and amino acids showed a decreasing trend, while the content of caffeine increased. The results of GC-MS and electronic nose show that the aroma substances were significantly different from other samples during the first stacking. As the types of aroma substances increased during the numerical control fermentation, the relative contents of aroma substances decreased. The aroma substances mainly included alcohols, aromatic hydrocarbons, ketones and aldehydes. Moreover, the aromatic hydrocarbon-like aroma substances were detected to be rich.

Key words: post-fermented Puer tea, mechanization, GC-MS, electronic nose, numerical control fermentation