Lee Jeehyun, Chambers Delores, Chambers Edgar
Department of Food Science and Nutrition, Pusan National University, 30 Jangjeon-Dong, Geumjeong-gu, Busan 609 735, Korea.
Sensory Analysis Center, Kansas State University, Manhattan, KS 66506-1407, USA.
Foods. 2013 Nov 29;2(4):554-571. doi: 10.3390/foods2040554.
Green teas in leaf form are brewed multiple times, a common selling point. However, the flavor changes, both sensory and volatile compounds, of green teas that have been brewed multiple times are unknown. The objectives of this study were to determine how the aroma and flavor of green teas change as they are brewed multiple times, to determine if a relationship exists between green tea flavors and green tea volatile compounds, and to suggest the number of times that green tea leaves can be brewed. The first and second brews of the green tea samples provided similar flavor intensities. The third and fourth brews provided milder flavors and lower bitterness and astringency when measured using descriptive sensory analysis. In the brewed liquor of green tea mostly linalool, nonanal, geraniol, jasmone, and β-ionone volatile compounds were present at low levels (using gas chromatography-mass spectrometry). The geraniol, linalool, and linalool oxide compounds in green tea may contribute to the floral/perfumy flavor. Green teas in leaf form may be brewed up to four times: the first two brews providing stronger flavor, bitterness, and astringency whereas the third and fourth brews will provide milder flavor, bitterness, and astringency.
叶状绿茶可以冲泡多次，这是一个常见的卖点。然而，多次冲泡的绿茶在感官和挥发性化合物方面的风味变化尚不清楚。本研究的目的是确定绿茶多次冲泡时香气和风味如何变化，确定绿茶风味与绿茶挥发性化合物之间是否存在关系，并建议绿茶叶的冲泡次数。绿茶样品的第一次和第二次冲泡提供了相似的风味强度。使用描述性感官分析测量时，第三次和第四次冲泡的风味较淡，苦味和涩味较低。在绿茶冲泡液中，大多是芳樟醇、壬醛、香叶醇、茉莉酮和β-紫罗兰酮等挥发性化合物，含量较低（使用气相色谱-质谱联用仪）。绿茶中的香叶醇、芳樟醇和氧化芳樟醇化合物可能有助于产生花香/香水味。叶状绿茶最多可以冲泡四次：前两次冲泡提供更强的风味、苦味和涩味，而第三次和第四次冲泡将提供较淡的风味、苦味和涩味。
