Food Science and Biotechnology

Korean Society of Food Science and Technology (한국식품과학회)
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Chemical Composition of Green Teas According to Processing Methods and Extraction Conditions

  • Kim, Young-Kyung (Department of Food Science and Technology, Ewha Womans University) ;
  • Oh, Yoo-Jin (Tea Research, Food Research Institute, Amorepacific Corporation) ;
  • Chung, Jin-Oh (Tea Research, Food Research Institute, Amorepacific Corporation) ;
  • Lee, Sang-Jun (Tea Research, Food Research Institute, Amorepacific Corporation) ;
  • Kim, Kwang-Ok (Department of Food Science and Technology, Ewha Womans University)
  • Published : 2009.10.31
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Abstract

This study examined the influence of manufacturing processes and extraction conditions on the chemical compositions of green tea. Green tea samples grown in various areas (Korea, China, and Japan) and processed by 4 different methods (steaming, pan-firing, steaming and pan-firing, and heavy roasting after steaming and pan-firing) were collected for study. The chemical compositions of the green tea extracts and infusions were different according to their processing methods and extraction conditions, including catechins, caffeine, and free amino acids contents. In all samples analyzed, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), and theanine were determined as the major catechins and free amino acid, respectively. Studies of samples grown in the same area (Jeju; Korea) showed that there were significant differences in the concentrations of catechins and caffeine in extract and infusion according to the processing methods. These results indicate that processing methods influenced the chemical compositions of the green tea extracts and infusions.

Keywords

References

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