DOI QR코드

DOI QR Code

A Review of Withering in the Processing of Black Tea

  • Deb, Saptashish (Koomber Tea Estate, Goodricke Group Limited) ;
  • Jolvis Pou, K.R. (Department of Agricultural Engineering, School of Technology, Assam University)
  • 투고 : 2016.08.22
  • 심사 : 2016.10.28
  • 발행 : 2016.12.01

초록

Purpose: Tea is the most frequently consumed drink worldwide, next to water. About 75% of the total world tea production includes black tea, and withering is one of the major processing steps critical for the quality of black tea. There are two types of tea withering methods: physical and chemical withering. Withering can be achieved by using tat, tunnel, drum, and trough withering systems. Of these, the trough withering system is the most commonly used. This study focuses on the different types of withering, their effect on the various quality attributes of tea, and other aspects of withering methods that affect superior quality tea. Results: During physical withering, tea shoots loose moisture content that drops from approximately 70-80% to 60-70% (wet basis). This leads to increased sap concentration in tea leaf cells, and turgid leaves become flaccid. It also prevents tea shoots from damage during maceration or rolling. During chemical withering, complex chemical compounds break down into simpler ones volatile flavor compounds, amino acids, and simple sugars are formed. Withering increases enzymatic activities as well as the concentration of caffeine. Research indicates that about 15% of chlorophyll degradation occurs during withering. It is also reported that during withering lipids break down into simpler compounds and catechin levels decrease. Improper withering can cause adverse effects on subsequent manufacturing operations, such as maceration, rolling, fermentation, drying, and tea storage. Conclusion: Freshly harvested leaves are conditioned physically and chemically for subsequent processing. There is no specified withering duration, but 14-18 h is generally considered the optimum period. Proper and even withering of tea shoots greatly depends on the standards of plucking, handling, transportation, environmental conditions, time, and temperature. Thus, to ensure consumption of high quality tea, the withering step must be monitored carefully.

키워드

참고문헌

  1. Baruah, A. M. 2003. Fermentation characteristics of some Assamica clones and process optimization of black tea manufacturing. Journal of Agricultural and Food Chemistry 51:6578-6588. https://doi.org/10.1021/jf030019w
  2. Baruah, D., L. P. Bhuyan and M. Hazarika. 2012. Impact of moisture loss and temperature on. biochemical changes during withering stage of black tea processing on four Tocklai released clones. Two and a Bud 59(2):134-142.
  3. Belitz, H. D., W. Grosch and P. Schieberle. 2009. Food chemistry, 4th revised and enlarged edition. Springer, Berlin 938-970.
  4. Bhagat, R. M., R. D. Baruah and S. Safique .2010. Climate and tea [Camellia sinensis (L.) O. Kuntze] production with special reference to North Eastern India: a review. Journal of Environmental and Research and Development 4(4):10171028.
  5. Bhatia, I. S. 1962. Chemical aspects of withering. Two and a Bud 9:26-30.
  6. Bhatia, I. S. 1964. The role of chemistry in tea manufacture. Two and a Bud 11:109-l 17.
  7. Bhuyan, L. P. and P. K. Mahanta. 1989. Studies on fatty acid composition in tea Camellia sinensis. Journal of the Science of Food and Agriculture 46:325-330. https://doi.org/10.1002/jsfa.2740460310
  8. Bokuchava, M. A. and N. I. Skobeleva. 1980. The biochemistry and technology of tea manufacture. CRC Critical Reviews in Food Science and Nutrition 12:303-370. https://doi.org/10.1080/10408398009527280
  9. Burton, S. J. A. 1995. Leaf handling project, part of B.Sc degree in Environmental Management, Silsoe College, Cranfield University, U.K.
  10. Chaturvedula, V. S. P. and I. Prakash. 2011. The aroma, taste, colour and bioactive constituents of tea. Journal of Medicinal Plants Research 5(11):2110-2124.
  11. Chen, Q., J. Zhao and S. Vittayapadung. 2008. Identification of the green tea grade level using electronic tongue and pattern recognition. Food Research International 41(5):500-504. https://doi.org/10.1016/j.foodres.2008.03.005
  12. Choudhury, R. 1970. Withering, serial No 185, K2 file, November 1970, Tocklai Experimental Station, Assam, Indian.
  13. Dev Choudhury, M. N. and K. L. Bajaj. 1980. Biochemical changes during withering of tea shoots. Two and a Bud 27:13-16.
  14. Fard, F. S., H. R. Ghassemzadeh and S. B. Salvatian. 2015. Impact of withering time duration on some biochemical properties and sensory quality attributes of black tea. Biological Forum-An International Journal 7(1):1045-1049.
  15. Ghodake, H. M., T. K. Goswami and A. Chakraverty. 2006. Mathematical modeling of withering characteristics of tea leaves. Drying Technology: An International Journal 24(2):159-164. https://doi.org/10.1080/07373930600558979
  16. Gupta, R. and S. K. Dey. 2010. Development of a productivity measurement model for tea industry. ARPN Journal of Engineering and Applied Sciences 5:16-25.
  17. Hazarika, M. and P. K. Mahanta. 1983. Some studies on carotenoids and their degradation in black tea manufacture. Journal of the Science of Food and Agriculture 34:1390-1396. https://doi.org/10.1002/jsfa.2740341212
  18. Heneberry, M. 2006. The little black book of tea: The essential guide to all things tea. Peter Pauper Press, New York.
  19. Hilton, P. J. 1975. Manufacture of tea in Central Africa. Tea Research Foundation of Central Africa, Mulanje, Malawi.
  20. Hussian, I., F. Khan, Y. Iqbal and S. J. Khalil. 2006. Investigation of heavy metals in commercial tea brands. Journal of Chemical Society of Pakistan 28:246-251.
  21. Jabeen, S., S. Alam, M. Saleem, W. Ahmad, R. Bibi, F. S. Hamid and H. U. Shah. 2015. Withering timings affect the total free amino acids and mineral contents of tea leaves during black tea manufacturing. Arabian Journal of Chemistry doi: 10.1016/j.arabjc.2015.03.011
  22. Jolvis Pou, K. R. 2016. Fermentation: The Key Step in the Processing of Black Tea. Journal of Biosystems Engineering 41(2):85-92. https://doi.org/10.5307/JBE.2016.41.2.085
  23. Katiyar, S. K. and H. Mukhtar. 1996. Tea in chemoprevention of cancer: epidemiologic and experimental studies. International Journal of Oncology 8:221-238.
  24. Kumar, S. and K. R. Jolvis Pou. 2016. Assessment of bio-energy potential in tea industries of India. Asian Journal of Agriculture and Rural Development 6(5):83-89. https://doi.org/10.18488/journal.1005/2016.6.5/1005.5.83.89
  25. Mahanta, P. K. and S. Boruah. 1989. Relationship between process of withering and aroma characteristics of black tea. Journal of the Science of Food and Agriculture 40:461-468.
  26. Motoda, S. 1979. Formation of aldehydes from amino acids by polyphenol oxidase. Journal of Fermentation Technology 57:395-399.
  27. Obanda, M., P. O. Owuor, R. Mangoka and M. M. Kavi. 2004. Changes in thearubigin fractions and theaflavin levels due to variations in processing conditions and their influence on black tea liquor brightness and total color. Food Chemistry 85:163-173. https://doi.org/10.1016/S0308-8146(02)00183-8
  28. Omiadze, N. T., N. I. Mchedlishvili, J. N. Rodrigez_Lopez, M. O. Abutidze, T. A. Sadunishvili, and N. G. Pruidze. 2014. Biochemical processes at the stage of withering during black tea production. Applied Biochemistry and Microbiology 50(4):394-397. https://doi.org/10.1134/S0003683814040103
  29. Orchard, J. E. 1991. Technical Report 1988-91. ODA TCO, Tea Research Foundation of Kenya, P.O. Box 820, Kericho, Kenya, 126.
  30. Owuor, P. O. and J. E. Orchard. 1989. Withering, annual report. Tea Research Foundation of Kenya 89-102.
  31. Owuor, P. O. and J. E. Orchard. 1992. Effects of storage time in a two-stage withering process on the quality of seedling black tea. Food Chemistry 45:45-49. https://doi.org/10.1016/0308-8146(92)90011-P
  32. Owuor, P. O., T. Tsushida, H. Horita and T. Murai. 1987. Effects of artificial withering on the chemical composition and quality of black tea. Tropical Science 27:159-166.
  33. Panda, H. 2011. A complete book on cultivation and manufacture of tea. Asia Pacific Business Press Inc., Delhi 24-42.
  34. Perera, K. P. W. C. and R. L. Wickremasinghe. 1972. Properties of tea polyphenol oxidase. Tea Quarterly 43:153-163.
  35. Ravichandran, R. and R. Parthiban. 1998. Changes in enzyme activities (polyphenol oxidase and phenylalanine ammonia lyase) with type of tea leaf and during black tea manufacture and the effect of enzyme supplementation of dhool on black tea quality. Food Chemistry 62(3):277-281. https://doi.org/10.1016/S0308-8146(97)00220-3
  36. Roberts, E. A. H. 1962. The chemistry of tea manufacture. Journal of the Science of Food and Agriculture 9:381-390.
  37. Roberts, E. A. H. 1963. The phenolic substances of manufactured tea. X. The creaming down of tea liquors. Journal of the Science of Food and Agriculture 14:700-705. https://doi.org/10.1002/jsfa.2740141003
  38. Sanderson, G. W. and H. N. Graham. 1973. On the formation of black tea aroma. Journal of Agricultural and Food Chemistry 21:576-585. https://doi.org/10.1021/jf60188a007
  39. Sanderson, G. W. 1964. The theory of withering in tea manufacture. Tea Quarterly 35:146-163.
  40. Saijo, R. 1977. Mechanisms of developing black tea aroma with special reference to alcoholic compounds. Japan Agricultural Research Quarterly 11:216-220.
  41. Sakata, K., M. Mizutani, S. Ma and W. Guo. 2004. Improvement of flavour quality of CTC black tea by glycosidases in tea leaves. International Journal of Tea Science 3:167-173.
  42. Sanyal, S. 2011. Tea manufacturing manual. Tea Research Association, Tocklai Experimental Station, Jorhat.
  43. Selvendran, R. R. 1969. Metabolism of nucleotide and phosphate esters in tea shoots during black tea manufacture. Tea Quality 40:93-98.
  44. Sharangi, A. B. 2009. Medicinal and therapeutic potentialities of tea (Camellia sinensis L.)-A review. Food Research International 42 (5-6):529-535. https://doi.org/10.1016/j.foodres.2009.01.007
  45. Takeo, T. and T. Tsushida. 1980. Changes in lipoxygenase activity in relation to lipid degradation in plucked tea shoots. Phytochemistry 19:2521-2522. https://doi.org/10.1016/S0031-9422(00)83910-2
  46. Takeo, T. 1984. Effect of the withering process on volatile compound formation during black tea manufacture. Journal of the Science of Food and Agriculture 35:84-87. https://doi.org/10.1002/jsfa.2740350114
  47. Taylor, S., D. Baker, P. Owuor, J. Orchard, C. Othieno and C. Gay. 1992. A model for predicting black tea quality from the carotenoid and chlorophyll composition of fresh green tea leaf. Journal of the Science of Food and Agriculture 58:185-191. https://doi.org/10.1002/jsfa.2740580205
  48. Tomlins, K. I. and A. Mashingaidze. 1997. Influence of withering, including leaf handling, on the manufacturing and quality of black teas-a review. Food Chemistry 60(4):573-580. https://doi.org/10.1016/S0308-8146(97)00035-6
  49. Ullah, M. R. and P. C. Roy. 1982. Effect of withering on the polyphenol oxidase level in the leaf. Journal of the Science of Food and Agriculture 33:492-495. https://doi.org/10.1002/jsfa.2740330515
  50. Ullah, M. R. 1984. A reappraisal of withering process in black tea manufacture. I. Physical and chemical withers and their effects on tea liquors. Two and a Bud 31:20-24.
  51. Wickremasinghe, R. L. 1975. Tea. Advances in Food Research 24:229-286.
  52. Wilkie, A. S. 1995. Leaf handling study. TRF QNL 120:26-38.
  53. Wright, A. J. and M. J. Fishwick. 1979. Lipid degradation during manufacture of black tea. Phytochemistry 18:1511-1513 https://doi.org/10.1016/S0031-9422(00)98485-1
  54. Yamanishi, T., A. Kobayashi, H. Sata, H. Nakanura, K. Oswa, A. Uchida, S. Mori and R. Saijo. 1966. Flavour of black tea. Part IV. Changes in flavour constituents during the manufacture of black tea. Agricultural and Biological Chemistry 30:784-792. https://doi.org/10.1271/bbb1961.30.784
  55. Yan, S. H. 2007. NIR evaluation of the quality of tea and its market price. Spectroscopy Europe 19(2):16-19.
  56. Zheng, X. Q., Q. S. Li, L. P. Xiang and Y. R. Liang. 2016. Recent advances in volatiles of teas. Molecules 21(338):1-12.

피인용 문헌

  1. CsGOGAT Is Important in Dynamic Changes of Theanine Content in Postharvest Tea Plant Leaves under Different Temperature and Shading Spreadings vol.65, pp.44, 2017, https://doi.org/10.1021/acs.jafc.7b04552
  2. ) provides new insights into the safe and effective alteration of tea flavor and function pp.1549-7852, 2019, https://doi.org/10.1080/10408398.2018.1552245