Astringency of Kamairi-cha and Sen-cha

作者：Matsuo Hirofumi^*; Hayashi Nobuyuki; Ujihara Tomomi; Fujita Susumu; Tatsuno Toshihiro; Mitarai Masafumi; Gejima Yoshinori; Toyomitsu Yukio; Kinoshita Osamu; Taniguchi Tomohiro

来源：Journal of the Japanese Society for Food Science and Technology, 2012, 59(1): 6-16.

• astringency
• a taste sensor system
• Kamairi-cha
• catechin
• water-soluble pectin

In the present study, we evaluated the astringencies of infusions of Kamairi-cha and Sen-cha using a taste sensor system. The results obtained using the taste sensor system showed that the astringency of Kamairi-cha was lower than that of Sen-cha and, that the astringency of Sen-cha decreased with increasing steaming duration. Both catechin and water-soluble pectin contents were lower in the Kamairi-cha infusion than in the Sen-cha infusion. Moreover, the elution ratio of water-soluble pectin in Kamairi-cha was lower than in Sen-cha. This difference is attributed to the shorter duration of the pressing process for the tea leaves used in the production of Kamairi-cha than for the production of Sen-cha. In contrast, as steaming duration is increased, the water-soluble pectin content in the tea leaves increases. However, water-soluble pectin content did not demonstrate an upward trend during post-steaming drying at a constant rate. Based on these results, we surmised that the water-soluble pectin content in tea leaves increases when leaves are heated to approximately 90-100 degrees C. The results of multiple linear regression analysis of the obtained data showed that astringency was related to the catechin and water-soluble pectin content in the tea infusion and astringency increased as content of catechins increased and content of water-soluble pectin decreased.

• 出版日期2012