关键词: 普洱茶, 塔宾曲霉, 茶褐素, 液态发酵, 固态发酵, 化学成分, 居里点热裂解气相色谱-质谱联用

Abstract: Theabrownins (TB) were extracted from instant Pu-erh tea made by submerged fermentation using Aspergillus tubingensis and from ripened Pu-erh made by conventional solid-state fermentation. Curie point pyrolysis gas chromatography-mass spectrometry (CP-Py-GC-MS) and colorimetry were used to analyze the TB composition of Pu-erh tea. Results showed that the contents of theabrownins, total polyphenols, total flavonoids, total catechins and amino acids in instant Pu-erh tea were significantly higher than those in ripened Pu-erh (P < 0.05), while the contents of total carbohydrate, polysaccharides and theaflavins were significantly lower in instant Pu-erh tea (P < 0.05). On the other hand, no significant difference in protein content between the two teas was observed (P > 0.05). At different Curie point pyrolysis temperatures (380 and 600 ℃), 12 and 9 compounds were found to be common to the pyrolysis products of TB from both tea samples. The majority of these pyrolysis products were phenolic compounds with caffeine being the most predominant.

Key words: Pu-erh tea, Aspergillus tubingensis, theabrownins, submerged fermentation, solid-state fermentation, chemical composition, Curie point pyrolysis gas chromatography-mass spectrometry (CP-Py-GC-MS)