Sung-Hee Choi1,2, Il-Doo Kim3, Sanjeev Kumar Dhungana4 and Do-Gong Kim1,2*
1Department of Won Buddism, Wonkwang University, Jeonbuk 54538, Korea.
2Tea & Tao Research Institute, Wonkwang University, Jeonbuk 54538, Korea.
3International Institute of Research & Development, Kyungpook National University,
Daegu 41566, Korea.
4School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea.
Pu-erh, a type of post-fermented dark tea, has attracted much attention of food scientists because of its health-promoting effects. pH, titratable acidity, color value, antioxidant potential and free amino acid contents of cultivated Pu-erh and Gushu Pu-erh teas extracted at 90 and 100°C were compared in this study. The pH of Gushu Pu-erh tea extract was slightly acidic than cultivated Pu-erh. Gushu Pu-erh contained higher antioxidant potentials and free amino acid content at the both extraction temperatures than the cultivated Pu-erh. The antioxidant potentials and free amino acid content were high in the tea extracted at 100°C. The results of this study showed that Gushu Pu-erh tea extracted at 100°C for 3 min with 30 s of shaking yields high amounts of phenolics and free amino acids.
Keywords: Antioxidant potential, Cultivated Pu-erh, Extraction temperature, Gushu Pu-erh.