Quantitative Analysis of the Taste and Its Correlation Research of Chemical Constitutes of Green Tea

The study was conducted to quantitatively analyze the taste attributes of green tea and its correlation with chemical components of green tea. Different kinds of green tea processed with different fresh tea leaves and process technologies were chosen to study the taste quality. Sodium glutamate, glucose, caffeine and EGCG were chosen as the standard chemical components from tea to establish standard curves of umami taste, sweet taste, bitter taste and astringent taste. According to the standard curves, the taste attributes of green tea were quantitatively analyzed. And correlations analysis between taste attributes and chemical components were also determined. There were significant positive correlations between aroma, taste and sensory quality. Umami taste and bitter taste were found significantly positively and negatively correlated with taste quality. And there were also found significant positive correlations between umami taste and sweet taste, bitter taste and astringent taste. But significant negative correlations between umami taste and bitter taste and astringent taste, sweet taste and bitter taste and astringent taste were found. The contents of polyphenols, caffeine, water extract, gallic acid, catechins(EGCG, EGC, ECG and total catechins) and phenylalanine were found significantly positively correlated with bitter taste, astringent taste and negatively correlated with umami taste. Total sugar content was found significantly positively with sweet tase. Sodium glutamate contents of green tea infusion were found significantly positively correlated with umami taste and negatively correlated with bitter taste. This study established a method for quantitative analysis of taste of tea, and provided fundamental basis for tea grading and taste chemistry research.