Green tea from purple leaf coloured tea clones in Kenya-their quality characteristics

Food Chemistry

Volumn 141, Issue 2, 2013, Pages 769-775

  Kilel, E C ^a   Faraj, A K ^a   Wanyoko, J K ^b   Wachira, F N ^b   Mwingirwa, V ^c  

^a EGERTON UNIVERSITY   (Kenya)

^b TEA RESEARCH FOUNDATION OF KENYA   (Kenya)

^c Kenya Tea Development Agency   (Kenya)

Author keywords

Caffeine; Catechin quality index; Green tea; Purple leaf coloured teas; Theanine

Indexed keywords

BEVERAGES; CAFFEINE; FISH; FLAVONOIDS; ORGANIC COMPOUNDS; PHENOLS; VITAMINS;

GREEN TEA; PURPLE LEAF COLOURED TEAS; QUALITY CHARACTERISTIC; QUALITY INDICES; QUALITY PARAMETERS; REFERENCE STANDARD; THEANINE; TOTAL POLYPHENOLS;

CLONING;

CAFFEINE; CATECHIN; GALLIC ACID; POLYPHENOL; THEANINE;

ARTICLE; CLONE; KENYA; NONHUMAN; PLANT LEAF; QUALITY CONTROL; TEA;

EID: 84878223261     PISSN: 03088146     EISSN: 18737072     Source Type: Journal    
DOI: 10.1016/j.foodchem.2013.03.051     Document Type: Article

References (35)

1. Alcazar, A., Ballesteros, O., Jurado, J. M., Pablos, F., and Martin., M. J., & Vilches, J. L. (2007). Differentiation of green, white, black, oolong and pu-erh teas according to their free amino acids content. Journal of Agricultural and Food Chemistry, 55, 5960-5965. (Pubitemid 47235643)
2. Anonymous (1998). TRFK annual report for 1998. Tea research foundation of Kenya. pp. 32-33.
3. Anonymous (2010). International tea committee. annual bulletin of statistics supplements, London.
4. Balentine, D. A., and Harbowy., M. E., & Graham, H. N. (1998). In G. A. Spiller (Ed.), Caffeine (pp. 35-72). Boca Raton: CRC Press.
5. Caffin, N., D'Arcy, B., Yao, L. & Rintoul, G. (2004). Developing an index of quality for Australian tea. Rural industries research and development corporation publication No. 04/033. ISBN 0 642 58743 4.
6. Chu, D. C. (1997). In T. Yamamoto, L. R. Juneja, D. C. Chu, & M. Kim (Eds.), Chemistry and Applications of Green Tea (pp. 1-11). Boca Raton: CRC Press.
7. Deng, W. W., Ogita, S., & Ashihara, H. (2008). Biosynthesis of theanine (ethylamino-L-glutamic acid) in seedlings of Camellia sinensis. Phytochemistry Letters, 1, 115-119.
8. Fernandez, P. L., Pablos, F., Martin, M. J., & Gonzalez, A. G. (2002). Study of catechin and xanthine tea profiles as geographical tracers. Journal of Agricultural and Food Chemistry, 50, 1833-1839. (Pubitemid 34259975)
9. Fiuza, S. M., Gomes, C., Teixeira, L. J., Giraoda Cruz, M. T., Cordeiro, M. N., Milhazes, N., et al. (2004). Phenolic acid derivatives with potential anticancer properties - A structure - Activity relationship study. Part 1. Methyl, prophyl and octyl esters of caffeic and gallic acids. Bioorganic, Medicinal Chemistry, 12(13), 3581-3589. (Pubitemid 38746860)
10. Hara, Y., and Luo., S. J., Wickremasinghe, R. L., & Yamanishi, T. (1995). Special issue on tea. Foods Review International, 11, 371-545.
11. Hara, Y. (2001). Green tea: Health benefits and applications. New York, USA: Marcel Dekker, Inc.
12. Harbowy, M. E., & Balentine, D. A. (1997). Tea chemistry. Critical Review Plant Science, 16(5), 415-480.
13. Hu, B., Wang, L., Zhou, B., Zhang, X., Sun, Y., & Ye, H. (2009). Efficient procedure for isolating methylated catechins from green tea and effective simultaneous analysis of ten catechins, three purine alkaloids, and gallic acid in tea by high performance liquid chromatography with diode array detection. Journal of Chromatography, A, 1216, 3223-3231.
14. Hung, Y. T., and Chen., P. O., Chen, R. L. C., & Cheng, T. J. (2010). Sequential determination of tannin and total amino acid contents in tea for taste assessment by a fluorescent flow-injection analytical system. Food Chemistry, 118, 876-881.
15. Juneja, L. R., and Chu., D. C., Okubo, T., Nagato, Y., & Yokogoshi, H. (1999). L-theanine - A unique amino acid of green tea and its relaxation effect in humans. Trends in Food Science and Technology, 10, 199-204.
16. Keenan, E. K., Finnie, M. D. A., Jones, P. S., and Rogers., P. J., & Priestley, C. M. (2011). How much theanine in a cup of tea? Effects of tea type and method of preparation. Food Chemistry, 125, 588-594.
17. Kerio, L. C., and Wachira., F. N., Wanyoko, J. K., & Rotich, M. K. (2011). Characterization of anthocyanins in Kenyan teas: Extraction and identification. Food Chemistry, 131(1), 31-38.
18. Kimura, K., Ozeki, M., Juneja, L. R., & Ohira, H. (2007). L-theanine reduces psychological and physiological stress responses. Biological Psychology, 74, 39-45. (Pubitemid 44781395)
19. Kito, M., Kokura, H., Izaki, J., & Sasaoka, K. (1968). Theanine, a precursor of the phloroglucinol nucleus of catechins in tea plants. Phytochemistry, 7, 599-603.
20. Lee, N. Y. (2007). Development of gallic acid-conjugated linoleic acid ester as novel functional materials and its biological activity. Thesis. Korea: Chonbuk National University, p. 48.
21. Lin, J. K., & Liang, Y. C. (2000). Cancer chemoprevention by tea polyphenols. Proceedings of the National Science Council Republic of China B, 24(1), 1-13.
22. Lu, S. H. (1987). Tea evaluation and inspection (2nd ed.). Beijing: Agricultural Press.
23. Nobre, A. C., Rao, A., & Owen, G. N. (2008). L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pacific Journal of Clinical Nutrition, 17, 167-168.
24. Obanda, M., and Owuor., P. O., & Taylor, S. J. (1997). Flavanol composition and caffeine content of green leaf as quality potential indicators of Kenyan black teas. Journal of Science Food and Agriculture, 74(2), 209-215. (Pubitemid 27347397)
25. Peng, L., Song, X., Shi, X., Li, J., & Ye, C. (2008). An improved HPLC method for simultaneous determination of phenolic compounds, purine alkaloids and theanine in Camellia species. Journal of Food Composition and Analysis, 21, 559-563.
26. Pourmorad, F., and Husseinimehr., S. J., & Shahabimajd, N. (2006). Antioxidant, phenol and flavanoid contents of some selected Iranian medicinal plants. African Journal of Biotechnology, 5, 1142-1145. (Pubitemid 43876623)
27. Rogers, P. J., and Smith., J. E., Heatherley, S. V., & Pleydell-Pearce, C. W. (2008). Time for tea: Mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together. Psychopharmacology (Berl), 195, 569-577. (Pubitemid 350160491)
28. Seetohul, L. N., Islam, M., O'Hare, W. T., & Ali, Z. (2006). Discrimination of teas based on total luminescence spectroscopy and pattern recognition. Journal of Science of Food and Agriculture, 86, 2092-2098. (Pubitemid 44544810)
29. Wachira, F. N., & Kamunya, S. (2005). Kenyan teas are rich in antioxidant. Tea, 26, 81-89.
30. Wang, H., and Provan., G. J., & Helliwell, K. (2000). Tea flavonoids: Their functions, utilisation and analysis. Trends in Food Science and Technology, 11, 152-160. (Pubitemid 32122540)
31. Wang, L., Xu, R., Hu, B., Li, W., Sun, Y., & Tu, Y. (2010). Analysis of free amino acids in Chinese teas and flower of tea plant by high performance liquid chromatography combined with solid-phase extraction. Food Chemistry, 123, 1259-1266.
32. Yang, D. J., and Hwang., L. S., & Lin, J. T. (2007). Effects of different steeping methods and storage on caffeine, catechins and gallic acid in bag tea infusions. Journal of Chromatography, A, 1156, 312-320. (Pubitemid 46935715)
33. Yuan, Y.C. (1962). Chemical and biochemical studies on tea catechins. Annual Report Tea Research Institute Chinese Academy. Agricultural Science, 217-222.
34. Zhao, J. W., and Chen., Q. S., & Huang, X. Y. (2006). Qualitative identification of tea categories by near infrared spectroscopy and support vector machine. Journal of Pharmaceutical and Biomedical Analysis, 41, 1198-1204.
35. Zuo, Y., Chen, H., & Deng, Y. (2002). Simultaneous determination of catechins, caffeine and gallic acid in green tea, Oolong, black and Puerh teas using HPLC with a photodiode array detector. Talanta, 57, 307-361.