Optimizing the extraction parameters of epigallocatechin gallate using conventional hot water and ultrasound assisted methods from green tea

Epigallocatechin gallate (EGCG) is the main polyphenol present in green tea and is also known to possess various beneficial health effects. Extractions of EGCG, epigallocatechin (EGC), epicatechin gallate (ECG), and epicatechin (EC) from green tea were investigated by both conventional hot water extraction and ultrasound assisted extraction (UAE) with water and ethanol. Response Surface Methodology was used in order to optimize the extraction conditions for obtaining maximum amount of EGCG in the extracts. Pilot scale conventional hot water extraction and UAE with water in continuous flow mode were also conducted for industrial use. UAE with ethanol was significantly (p