earticle

영어

Changes in lipophillic pigments concentration and its relation to color of fresh green tea liquor during heattreatment were studied. The results showed liquor greenness decreased markedly with extension of incubation time at 55oC,while the brightness and yellowness changed a little. Significant increase in ‘a’ and ‘b’ values of tea liquor was observed at95oC. Color change of liquor at 55oC was accompanied by a decrease in the level of chlorophylls, lutein and neoxanthin, andan increase in the pheophytins and β-carotene levels. However, all pigments except β-carotene decreased with time extensionat 95oC. Significant correlation was found between pigments and color difference index. The browning of fresh green tealiquor was attributed to vicissitudes of lipophillic pigments during heat treatment, especially to the change of chlorophylls/pheophytins ratio. Result also showed addition of Zn2+ at 1.6µmol/L could partially alleviate the decrease in greenness duringheat treatment.