The γ-aminobutyric acid(GABA) contents in 45 tea samples were determined by colorimetric method,high performance liquid chromatography(HPLC) and amino acids analyser.The results demonstrated that there was no significant difference in GABA content in tea between determination by HPLC and determination by amino acids analyser.There were significant differences(P<0.01) in GABA content in Pu-erh tea,black tea,white tea and yellow tea between colorimetric method and HPLC method.The GABA contents in Pu-erh tea a...