Objective Various utensils and conditions applied for baking the regional specialty Wusa roasted tea were compared in accordance to the quality and functional ingredient contents of the resulting teas.

Methods Base on the traditional Wusa roasted tea making procedures, experimental Qianxi green teas were baked after optimization from 45 combined conditions using an iron wok at 280 ℃ for 3 m (K7), a clay pot at 220 ℃ for 4 m (K14), bamboo slabs at 110 ℃ for 2 m (K22), seashells at 90 ℃ for 9 m (K30), or banana leaves at 100 ℃ for 6 m (K45). The tea samples made were evaluated by a sensory panel and analyzed for chemical composition, aromatics, and serum lipid-lowering and antioxidant activities.

Results The average contents of water extract, polyphenols, soluble sugar, flavonoids, caffeine, and free amino acids in the 5 tea samples were 48.45%, 16.28%, 2.30%, 2.38%, 3.49%, and 4.27%, respectively. The teas carried the unique sensory quality of a typical Wusa roasted tea and contained 124 aromatic substances, mostly hydrocarbons and alcohols. The PCA and chemical analysis showed 22 of the aromatics contributed to the floral-woody, woody, and fennel-like notes of the teas. Among the various baking methods, K14 and K30 elevated the serum lipid-lowering and antioxidant activities with the capacities of adsorbing oil at the rates of 0.71 g·g⁻¹ and 1.15 g·g⁻¹, respectively. The tea produced by K14, at the concentration of 10 mg·mL⁻¹, had a binding rate with sodium glycocholate of 67.15% and with sodium taurocholate of 63.29%.

Conclusion K14, the process that baked the tea in a clay pot at 220 ℃ for 4 m, appeared to yield the most desirable overall properties for a Wusa roasted tea.