Physicochemical Properties of Powdered Green Teas in Korea

국내 시판 가루녹차의 이화학적 품질특성

  • Received : 2009.09.16
  • Accepted : 2009.10.30
  • Published : 2010.02.28

Abstract

This study was conducted to compare the physicochemical properties of powdered green teas produced in Korea and Japan including particle size, color, chlorophyll, caffeine and theanine. The average particle size of Korean powered green tea ($14.63-25.39\;{\mu}m$) was similar to that of Japanese powdered green tea ($15.46-21.02\;{\mu}m$). The surface color of shade-cultivated Haenam Green Tea (HN-1) had the highest negative 'a' value, which represents 'green' color. When the TCD (total color difference value) was measured in the samples, HN-1 was most similar to the premium powdered green tea of Japan (JA-1). Domestic shade-cultivated powdered green teas had 1.5-2 times greater chlorophyll content than powdered green teas produced from plants that were not cultivated in the shade. The presence of chlorophyll a resulted in a higher intensity of green color than the presence of chlorophyll b. A significant negative correlation was also observed between the color and the chlorophyll a, chlorophyll b and total chlorophyll contents. Specifically, chlorophyll a had the greatest impact on the green color of powdered green tea. The content of catechins, caffeine and theanine in Korean powdered green teas ranged from 14.679-20.128, 1.496-3.237 and 0.926-1.977 g/100 g, respectively. The caffeine and theanine contents were high in shade-cultivated powdered green teas. Based on the above results, domestic powdered green teas cultivated under shaded conditions had a quality similar to that of medium-quality green teas produced in Japan, and the overall quality of Korean powdered green tea was poorer than that of Japanese powdered green tea.

본 연구는 국내 시판 가루녹차 및 일본 가루녹차(말차)를 대상으로 입도, 색도, 클로로필, 카테킨, 카페인 및 테아닌 등 품질특성을 비교하였다. 국내산 가루녹차의 평균입도는 $14.63-25.39\;{\mu}m$의 범위로 일본산 가루녹차 $15.46-21.02\;{\mu}m$와 유사하였다. 가루녹차 표면의 색을 측정한 결과 녹색을 나타내는 a의 음의 값은 해남산 차광 재배 녹차인 HN-1이 -9.51로 가장 높았고, 색 정도를 평가하기 위해 일본산 상품인 JA-1을 기준으로 TCD값을 구한 결과 국내 시판 가루녹차 중 HN-1의 값이 3.71로 일본산 고급 가루녹차 색과 가장 유사한 것으로 나타났다. 클로로필 분석 결과 국내산 차광 재배 가루녹차의 총클로로필 함량은 339-592 mg/100 g으로 무차광 재배 가루녹차의 170-340 mg/100 g 보다 1.5-2배 정도 더 많이 함유되어 있었고 녹색도가 높을수록 클로로필 a가 클로로필 b 보다 더 많이 함유되어 있었다. 가루녹차의 색도 a값은 클로로필 a, b 및 총클로로필 함량과 모두 유의적인 역의 상관관계가 있는 것으로 나타났으며 특히 가루녹차의 녹색은 클로로필 a의 영향이 가장 큰 것으로 나타났다. 녹차의 주요성분인 카테킨, 카페인 및 테아닌 분석결과 국내산 가루녹차의 총카테킨 함량은 14.679-20.128 g/100 g, 카페인 함량은 1.496-3.237 g/100 g, 테아닌 함량은 0.926-1.977 g/100 g 함유되어 있었으며 카테킨 함량은 산지 및 차광유무에 따른 경향은 나타나지 않았으나 카페인과 테아닌 함량은 차광 재배한 가루녹차에 더 많이 함유되어 있었다. 본 실험결과 국내산 가루녹차의 품질은 차광 재배한 녹차의 경우 일본산 중품에 해당하는 값을 나타냈으나 전체적으로 일본 가루녹차에 비해 품질이 떨어지는 경향을 나타냈다.

Keywords

References

  1. Kim JT. Science and Culture of Tea. Borimsa Publishing Co., Seoul, Korea. pp. 157-248 (1996)
  2. Nakabayashi T, Ina K, Sakata K. Chemistry and Function of Green, Black and Oolong tea. Kogagu Press, Tokyo, Japan. pp. 20-51 (1994)
  3. Matsuzaki TL, Hara Y. Antioxidative activity of the leaf catechins. J. Agric. Chem. Soc. Japan 59: 129-134 (1985)
  4. Yoshioka H, Sugiura K, Kawahara R, Hujita T, Makino M, Kamiya M, Tsuyumu S. Formation of radicals and chemiluminescence during the auto- oxidation of the catechins. Agri Biol. Chem. Tokyo 55: 2717-2723 (1991) https://doi.org/10.1271/bbb1961.55.2717
  5. Song JM, Park KD, Lee KH, Byun YH, Park JH, Kim SH, Kim JH, Seong BL. Biological evaluation of anti-influenza viral activity of semisynthetic catechin derivatives. Antivir. Res. 76: 178-185 (2007) https://doi.org/10.1016/j.antiviral.2007.07.001
  6. Khan SM, Kour G. Subacute oral toxicity of chlorpyriphos and protective effect of green tea extract. Pestic. Biochem. Phys. 89: 118-123 (2007) https://doi.org/10.1016/j.pestbp.2007.04.005
  7. Mohan KVP, Gunasekaran P, Varalakshmi E, Hara Y, Nagini S. In vitro evaluation of the anticancer effect of lactoferrin and tea polyphenol combination on oral carcinoma cells. Cell Biol. Int. 31: 599-608 (2007) https://doi.org/10.1016/j.cellbi.2006.11.034
  8. Higdon JV, Frei B. Tea catechins and polyphenols: Health effects, metabolism, and antioxidant functions, Cri. Rev. Food Sci. 43: 89-143 (2003) https://doi.org/10.1080/10408690390826464
  9. Tang S, Kerry JP, Sheehan D, Buckley DJ, Morrissey PA. Antioxidative effect of added tea catechins on susceptibility of cooked red meat, poultry, and fish patties to lipid oxidation. Food Res. Int. 34: 651-657 (2001) https://doi.org/10.1016/S0963-9969(00)00190-3
  10. Lee JW, Do JH. Market trand of health functional food and prospect of ginseng market. J. Ginseng Res. 29: 206-214 (2005) https://doi.org/10.5142/JGR.2005.29.4.206
  11. Chung DH. Components and Efficacy of Tea. Hongikjae, Seoul, Korea. pp. 71-73 (2004)
  12. Park JH, Lim KC. Growth and constituents of tea shoots for powder green tea. J. Medicinal Crop Sci. 10: 379-383 (2002)
  13. Kim KS, Kouzkue N, Han JS. Comparison of the ingredients at powdered green teas commercialized in Korea and Japan. Korean J. Food Culture 19: 177-183 (2004)
  14. Jung DW, Park SI. Preparation of drinkable yoghurt added with green tea powder. Korean J. Food Nutr. 18: 349-356 (2005)
  15. Park SI. Application of green tea powder for sikhe preparation. Korean J. Food Nutr. 19: 227-233 (2006)
  16. Caldwell CR, Britz SJ. Effect of supplemental ultraviolet radiation on the carotenoid and chlorophyll composition of green house-grown leaf lettuce (Lactuca sativa L.) cultivars. J. Food Compos. Anal. 19: 637-644 (2006) https://doi.org/10.1016/j.jfca.2005.12.016
  17. Hu B, Wang L, Zhou B, Zhang X, Sun Y, Ye H, Zhao L, Hu Q, Wang G, Zeng X. Efficient procedure for isolating methylated catechins from green tea and effective simultaneous analysis of ten catechins, three purin alkaloids, and gallic acid in tea by high-performance liquid chromatography with diode array detection. J. Chromatogr. A 1216: 3223-3231 (2009) https://doi.org/10.1016/j.chroma.2009.02.020
  18. Youn KS. Absorption characteristics of green tea powder as influenced by particle size. J. Korean Soc. Food Sci. Nutr. 33: 1720-1725 (2004) https://doi.org/10.3746/jkfn.2004.33.10.1720
  19. Park JH. Studies on chemical composition in korean native tea plants. PhD thesis, Chonnam National University, Kwangju, Korea (1997)
  20. Goto T, Yoshida Y, Kiso M, Nagashima H. Simultaneous analysis of individual catechins and caffeine in green tea. J. Chromatogr. A 749: 295-299 (1996) https://doi.org/10.1016/0021-9673(96)00456-6