An Easy Extracting Method for the Colorimetric Determination of Tea Leaf Tannin

Abstract

With the colorimetric determination of tannin a labor-saving preparation of estimating solution was investigated in order to facilitate a large number of determinations.
A weighed sample (1-2g.) of plucked tea shoots cut as wide as 5mm. was taken into 25 ml. of aqueous acetone and was stood overnight at room-temperature.
By this simple treatment tannin in the shoot was almost completely extracted in acetone solution. And it was shown that this solution was applicable for the determination by the ferrous tartrate method.
Further this solution was tested for the availability on the determination of chlorophyl, but it was impossible to attain the aim owing to a considerable degradation of chlorophyl.