Study on brewing technology of black tea with suitable taste

Abstract

Objective: This study aimed to explore the upper limit and technical parameters of black tea brewing with suitable taste and establish the relative brewing method system of daily drinking. Methods: The black tea soup was prepared by sensory evaluation method and diluted in a gradient with one bud and two leaves and then was tasted and scored by 50 volunteers to determine the appropriate taste consistency. On the basis of determining the suitable taste concentration, the quality concentrations of water extract, theaflavin and theaflavin under the suitable taste were used as the indexes to optimize and screen the technical parameters of black tea brewing each time and the brewing times under the appropriate taste. Results: When the mass concentrations of aqueous extract, theaflavin and thearubin in black tea soup were 1.40, 0.04 and 0.60 mg/mL respectively, and it had a suitable taste. The first brewing was made with a tea-water ratio (mtea∶Vwater) of 1∶100 (g/mL) and pure water at 82 ℃ for 4.5 min, and the second brewing was made with a tea-water ratio (mtea∶Vwater) of 1∶50 (g/mL) and pure water at 86.0 ℃ for 3.5 min.The tea broth obtained in both times had a suitable taste and reached the mass concentration of water extract, theaflavin and theaflavin of suitable taste. However, after the third brewing with tea-water ratio (mtea∶Vwater) of 1∶50 (g/mL) and 97.3 ℃ pure water for 6.4 min, the resulting tea broth was too light in taste, and the water extracts and theaflavins also failed to reach the quality concentration requirement under suitable taste. Conclusion: It is appropriate to brew black tea for two times with appropriate taste kept.

Keywords

• black tea
• drinking
• brewing technology
• suitable taste
• response surface methodology