Abstract: Water soluble tea green pigment(TGP) were extracted from low grade tea leaf and waste tea etc.Physico chemical properties and processes on saponification and copper substitution reaction were investigated.Results showed that optimum condition of saponification is sodium hydroxide 1% for 90 min, temperature of water bath 80℃.At pH value 3.0, temperature of water bath 80℃ for 60 min, a high proportion sodium copper chlorophyllin was achieved.The pH value in the range of 2.2-5.0 had no effect on the pigment.Heat and most of metal ions exerted insignificant effect, while ascorbic acid had protective effect on the tone of pigment.

Key words: tea green pigment, saponification