Study on producing pu-erh tea cream by extraction of tea at high temperature and pressure

Pu-erh tea cream is a special instant tea product in Yunnan. However, the aroma and taster of tea cream was poor for that the method of extraction of tea was cook, presently. So the extraction methods of tea need improve. In this work the extraction of tea at high temperature and pressure was investigated using a high pressure steam sterilizer and response surface methodology. The results of assays by response surface methodology showed that the optimal extract procedure was temperature (113℃) , time (14min) , and tea/water (1∶41g/mL) . The contents of polyphenols, free amino acids and water extract in tea extractions were 20.89%± 0.81%, 3.82%±0.35% and 37.89%±5.35%, respectively. Tea cream was produced by extract tea at the optimal condition, vacuum concentration, and drying. High performance liquid chromatography analysis (HPLC) and sensory evaluation revealed that the appearance, levels of chemical compound (catechins and caffeine) , and score of sensory evaluation of tea cream produced by high temperature and pressure were better than that produced by traditional methods. This work showed that extract tea using high temperature and pressure could improve the quality of tea cream, and it had some application potential in the instant tea producing.