Abstract
An analytical method for Japanese Agricultural Standard of green tea was studied.
First, one group of sencha (common green tea) including high, medium and low grade was subjected to chemical analysis as well as organoleptic test. The correlation coefficients between the content of main green tea constituents, i.e. total nitrogen, tannin (catechins), caffeine, water soluble matter, free reducing sugars and amino acids, and the scores of sensual evaluation, i.e. style, color, aroma, color of liquor and taste, were calculated. Among them that of total nitrogen was the highest on respective evaluation values.
Next, the correlation coefficients between total nitrogen and evaluation values were investigated on other three groups of green tea including commercially packed tea or foreign produced tea.
The total nitrogen content coincided significantly with the quality grade as to domestic tea, although it indicated only degree of style as to foreign produced one.
