돌외차(Gynostemma pentaphyllum Makino)의 당(糖)에 관한 연구

A Study on the Sugar Contents of Dolwoe Tea(Gynostemma pentaphyllum Makino)

돌외를 채취해서 잎과 줄기로 나누고 각각 실험실에서 차로 제조한 것과 제품으로 시판되고 있는 국산품과 일본산 제품 및 국산품 란은 것에 대해 총당, 환원당 및 유리당 함량을 측정하고 비교하였다. 제조된 돌외차의 총당과 환원당 함량은 줄기가 잎의 2배 많았으며 한국산 제품과 일본산 계품의 함량은 비슷하였으나 볶은 것은 볶지 않은 한국산보다 총당이 17.2% 감소하였으며, 환원당은 40.9% 감소하였다. 돌외차에 함유된 유리당은 rhamnose, fructose, glucose및 sucrose등이 확인되었다. 그 비율은 부위에 따라 차이가 많았으나 일반적으로 glucose> fructose> sucrose> rhamnose순으로 조성되었고 일본산 제품의 rhamnose 함량이 한국산 제품보다 6배 많았으며 볶은 것은 전체적으로 유리당 량이 낮았다.

The sugar contents of Dolwoe, which were prepared in the laboratory and marketed Korean products of Dolwoe, Japanese product of Dolwoe and Korean-roasted products of Dolwoe were analyzed and compared. The contents of total sugar and reducing sugar of stem in prepared Dolwoe tea were 2 times higher than those of leaf. The sugar content of Korean product was similar to that of Japanese, but the contents of total sugar and reducing sugar in Korean-roasted sample decreased to 17.2% and 40.9%, respectively. It was confirmed that free sugar in Dolwoe tea was composed of rhamnose, fructose, glucose and sucrose. The ratio of free sugar content was quite different between Dolwoe-leaf tea and Dolwoe-stem tea. Comparing the free sugar content in prepared Dolwoe tea, glucose was the highest followed by fructose, sucrose and rhamnose. On the other hand, in marketed Dolwoe tea, glucose was the highest substance and followed by fructose, rhamnose and sucrose. It was found that rhamnose content in Japanese product was approximately 6 times more than that of Korean.