Effects of microwave and ultrasound assisted extraction of main chemical components of tea

The extraction of tea is one of the most important technologies in the production of tea beverage and affects the quality of tea beverage. How to maintain the extracting rates of main chemical components in tea infusions and the quality of tea beverage under lower temperature and for a shorter time would be a key objective of the production of tea beverage. The effects of microwave and ultrasound on the extraction of main chemical components of tea were studied. The results showed that both extracting methods had better effects on the extraction of the main chemical components of tea. The contents of tea polyphenols, amino acid and caffeine in tea infusions produced by using both extracting methods reached those of normal extracting method. Both extracting methods had retaining effects on the extraction of protein and pectin. Main kinds of catechins in tea infusions extracted by different extracting methods were analyzed by HPLC. The results showed that catechin content extracted by using ultrasound from tea infusions was higher than those extracted by other methods from tea infusions. It was concluded that both ultrasound and microwave were suitable for the extracting process in the production of tea beverage.