Abstract: Objective: To optimize the extraction of instant green tea powder from tea leaves. Methods: On the basis of one-factor-at-a-time experiments, orthogonal array design L16(43) was used to optimize the extraction of instant green tea powder and the yield of green tea powder was investigated with respect to three extraction parameters including extraction temperature, tea leaves-to-water ratio and extraction time. Results: The importance of the three extraction parameters in affecting the yield of green tea powder declined in the following order: extraction temperature, tea leaves-to-water ratio and extraction time. The optimal extraction conditions of instant green tea powder were extraction temperature of 80 ℃, tea leaves-to-water ratio of 1:20 and extraction time of 80 min. Under the optimal extraction conditions, the yield of instant green tea powder reached up to (25.1 ±0.1)%. Conclusion: Orthogonal array design is suitable for optimizing the extraction of instant green tea powder from tea leaves. The optimized extraction parameters are reliable.

Key words: green instant tea powder, extraction, parameters, optimization