Evaluate the Perception of Bitterness in Black Tea and Green Tea at Different Brewing Conditions by Sensory Evaluation

Abstract

This study investigates the effect of brewing conditions on the sensory attributes of black tea (Darjeeling) and green tea (Gyokuro) with a specific focus on bitterness. In addition to bitterness, the study also examines how other key attributes such as sweetness, sourness, astringency, and dryness are influenced by different brewing ratios (tea/water). The tea samples were prepared at three different concentrations (2g/200ml, 4g/200ml, and 6g/200ml) for each type of tea and evaluated by using a sensory evaluation technique which was performed by 48 participants. The perception of bitterness, astringency, sourness, and dryness are all significantly enhanced when increasing the concentration of tea in both types of tea whereas the perception of sweetness decreases. However, statistical analysis indicates that bitterness intensity increased significantly with higher concentrations in both types of tea, but green tea (GT) has a more bitter taste than black tea (BT) at the same brewing conditions across all concentrations likely because it contains more tannins and catechins. The study revealed that brewing conditions, particularly the tea-to-water ratio critically influences sensory perception as high concentrations of tea lead to obtaining strong taste with reduction of sweetness. This research contributes to the understanding of how brewing variables impact the sensory profile of tea which plays an important role in the tea industry as it has implications for enhancing preferences of consumers and product development. Further research is suggested to investigate additional brewing conditions such as temperature and steeping time also including different varieties of tea with increase the sample size.