Preparation optimization of instant Pu'er tea powder

In order to improve the extraction of active ingredients in pu'er tea and the convenience of drinking,pressurized hot dip the optimal process to extract polyphenols in Pu'er tea was investigated,and the instant tea powder was obtained by extract drying,simultaneously the sensory index,amino acid and aroma components were analyzed. Results showed that the optimal extraction conditions were 130 ℃( temperature),0.185 MPa( pressure),30 min( time),and 1∶ 25( solid-liquid ratio),respectively.According to this method,the contents of TP and aqueous extract obtained from the extraction solution were 7.6% and 30.3%.After freezing and drying to obtain the tea powder with the optimum extraction conditions,the taste,aroma and decoction of the instant tea had no significant difference.Comparing to the spray drying samples in Pu'er tea,the content of total free amino acid in the freeze drying samples was higher,which showed significant differences. However,the tea flavor characteristics exhibited significant difference through different drying methods,while the process of freeze dry largely protected the aroma compounds in the samples.This research contributed to develop high amino acid of instant tea,provide a theoretical basis to promote deeply processing of tea industry in China with the tea aroma largely retained in Pu'er tea.