Oolong Çayın Üretimi, Bileşimi ve Sağlık Üzerine Etkisi

Dünyada yaygın olarak tüketilen çay, Camellia sinensis L. bitkisinin yapraklarından üretilmektedir. Polifenoller, aminoasitler, vitaminler, karbonhidratlar, kafein ve purin alkaloidler gibi bileşikler içermesi nedeniyle çay sağlık üzerine olumlu etkilere ve önemli fizyolojik özelliklere sahiptir. Çay fermente olmamış (yeşil çay), kısmen fermente olmuş (oolong çay) ve fermente olmuş (siyah çay) olmak üzere 3 tipte üretilmektedir. Siyah çay tüm dünyada, yeşil ve oolong çaylar ise özellikle Asya ve Kuzey Afrika'da tüketilmektedir. Dünyadaki toplam çay üretiminin %78ini siyah çay, %20sini yeşil çay ve %2den azını oolong çay oluşturmaktadır. Yeşil çay üretiminde enzimatik oksidasyonu önlemek için, taze çay yaprağı buharlanır veya fırınlanır. Siyah çay fermentasyon aşamasında enzimatik olarak tam olarak okside edilir. Oolong çay üretiminde ise orta seviyede enzimatik oksidasyona izin verilir. Oolong çayın fermentasyon derecesi tüketici isteklerine bağlı olarak %20 ile %60 arasında değişir. Tat ve renk açısından oolong çay, yeşil ve siyah çay arasında yer almaktadır. Kuru maddenin yeşil çayda %30-42sini, siyah çayda %3-10nu ve oolong çayda %8-20sini kateşinler oluşturmaktadır. Oolong çay siyah çaya göre daha yüksek antioksidan aktivite ve lipoksigenaz inhibitör aktiviteye sahiptir. Oolong çay, yeşil veya siyah çaydan daha güçlü antimutajenik aktivite göstermektedir. Oolong çayın kanser, obezite, ateroskleroz ve kalp hastalığı, diyabet ve alerji önleyici etkiye sahip olduğu da rapor edilmiştir. Bu derlemede, oolong çayın üretimi, bileşimi ve sağlık üzerine etkisi incelenmiş ve farklı çaylar ile karşılaştırılmıştır.

Production, Composition, and Health Effects of Oolong Tea

Tea, one of the most widely consumed beverages in the world, is produced from the leaves of the plant Camellia sinensis L.. Tea has important physiological properties and potential health benefits due to the presence of compounds such as polyphenols, amino acids, vitamins, carbohydrates, caffeine, and purine alkaloids. Tea is produced in three types as green tea (unfermented), oolong tea (partially fermented), and black tea (fully fermented). Black tea is consumed worldwide, whereas green and oolong teas are consumed mainly in Asia and North Africa. The total tea production in the world consists of about 78% black tea, 20% green tea and <2% oolong tea. In the production of green tea, the fresh leaves are steamed or roasted to avoid enzymatic oxidation. Black tea is fully oxidized during fermentation. Oolong tea is partially fermented to permit a moderate level of enzymatic oxidation during processing. The degree of fermentation of oolong tea leaves ranges from 20 to 60%, depending upon consumer demand. Oolong tea has a taste and color somewhere between green and black tea. Green tea contains 30-42% catechins in dry mass, while black tea contains 3-10% and oolong 8-20%. Oolong tea has a higher antioxidant activity and lipoxygenase inhibitory activity as compared to black tea. Oolong tea exhibits a stronger antimutagenic activity than green or black tea. Oolong tea is reported to have anticancer, antiobesity, antidiabetes, antiallergic effects, and prevent atherosclerosis and heart disease. In this review, the production, composition and health effects of oolong tea have been discussed.

PDF

___

Alcázar A, Ballesteros O, Jurado JM, Pablos F, Martiän MJ, Vilches JL, Navaloán A. 2007. Differentiation of green, white, black, oolong, and pu-erh teas according to their free amino acids content. J Agric Food Chem, 55: 5960-5965.
Anna GM. 2007. Antioxidant potential and radical scavenging activity of different fermentation degree tea leaves extracts. Int J Tea Sci, 6: 15-28.
Benzie IFF, Szeto YT. 1999. Total antioxidant capacity of teas by the ferric reducing antioxidant power assay. J Agric Food Chem, 47: 633-636.
Cabrera C, Artacho R, Giménez R. 2006. Beneficial effects of green tea- A review. Journal of the American College of Nutrition, 25: 7999.
Chen YL, Duan J, Jiang YM, Shi J, Peng L, Xue S, Kakuda Y. 2010. Production, quality, and biological effects of oolong tea (Camellia sinensis). Food Rev Int, 27: 1-15.
Davies MJ, Judd JT, Baer DJ, Clevidence BA, Paul DR, Edwards AJ, Wiseman SA, Muesing RA, Chen SC. 2003. Black tea consumption reduces total and LDL cholesterol in mildly hypercholesterolemic adults. J Nutr, 133:3298S- 3302S.
Dou J, Lee VSY, Tzen JTC, Lee MR. 2007. Identification and comparison of phenolic compounds in the preparation of oolong tea manufactured by semifermentation and drying processes. J Agric Food Chem, 55: 7462-7468.
Dufresne CJ, Farnworth ER. 2001. A review of latest research findings on the health promotion properties of tea. Journal of Nutritional Biochemistry, 12: 404-421.
Ekborg-Ott KH, Taylor A, Armstrong DW. 1997. Varietal differences in the total and enantiomeric composition of theanine in tea. J Agric Food Chem, 45: 353-363.
Gadow AV, Joubert E, Hansmann CF. 1997. Comparison of the antioxidant activity of rooibos tea (Aspalathus linearis) with green, oolong and black tea. Food Chem, 60 (1): 73-77.
Gardner EJ, Ruxton CHS, Leeds AR. 2007. Black tea-helpful or harmful? A review of the evidence. European Journal of Clinical Nutrition, 61: 3-18.
Graham HN. 1992. Green tea composition, consumption, and polyphenol chemistry. Prev Med, 21: 334-350.
Gupta S, Saha B, Giri AK. 2002. Comparative antimutagenic and anticlastogenic effects of green tea and black tea: a review. Mutation Research, 512: 37-65.
Han LK, Takaku T, Li J, Kimura Y, Okuda H. 1999. Antiobesity action of oolong tea. Int J Obesity, 23: 98-105.
Horranni R, Engelhardt UH. 2013. Determination of amino acids in white, green, black, oolong, pu-erh teas and tea products. J Food Comp Analy, 31: 94-100.
Hosoda K, Wang MF, Liao ML, Chuang CK, Iha M, Clevidence B, Yamamoto S. 2003. Anti-hyperglycemic effect of oolong tea in type 2 diabetes. Diabetes Care, 26, 17141718.
Jain A, Manghani C, Kohli S, Nigam D, Rani V. 2013. Tea and human health: The dark shadows. Toxic Letters, 220: 82-87.
Kim Y, Goodner KL, Park JD, Choi J, Talcott ST. 2011. Changes in antioxidant phytochemicals and volatile composition of Camellia sinensis by oxidation during tea fermentation. Food Chem, 129: 1331-1342.
Lee B, Ong C. 2000. Comparative analysis of tea catechins and theaflavins by high-performance liuqid chromatography and capillary electrophoresis. J. Chromatog A, 881: 439-447.
Lin JK, Lin CL, Liang YC, Lin-Shiau SY, Juan IM. 1998. Survey of catechins, gallic acid, and methylxanthines in green, oolong, pu-erh, and black teas. J Agric Food Chem, 46: 3635-3642.
Luczaj W, Skrzydlewska E. 2005. Antioxidative properties of black tea. Prev Med, 40: 910-918.
Mukhtar H, Ahmad N. 2000. Tea polyphenols: prevention of cancer and optimizing health. Am J Clin Nutr,71:1698S1702S. Nakai M, Fukui Y, Asami S, Toyoda-Ono Y, Iwashita T, Shibata H, MitsunagaT, Hashimoto F, Kiso Y. 2005.
Inhibitory effects of oolong tea polyphenols on pancreatic lipase in vitro. J Agric Food Chem, 53: 4593-4598.
Pan M-H, Liang Y-C, Lin-Shiau S-Y, Zhu N-Q, Ho C-H, Lin JK. 2000. Induction of apoptosis by the oolong tea polyphenol Theasinensin A through cytochrome C release and activation of caspase-9 and caspase-3 in human U937 cells. J Agric Food Chem, 48: 6337-6346.
Rumpler W, Seale J, Clevidence B, Judd J, Wiley E, Yamamoto S, Komatsu T, Sawaki T, Ishikura Y, Hosoda K. 2001. Oolong tea increases metabolic rate and fat oxidation in men. J Nutr, 131: 2848-2852.
Sano M, Suzuki M, Miyase T, Yoshino K, Yamamoto MM. 1999. Novel antiallergic catechin derivatives isolated from oolong tea. J Agric Food Chem, 47: 1906-1910.
Satoh E, Tohyama N, Nishimura M. 2005. Comparison of the antioxidant activity of roasted tea with green, oolong, and black teas. Int J Food Sci Nutr, 56: 551-559.
Sereshti H, Samadi S, Jalali-Heravi M. 2013. Determination of volatile components of green, black, oolong and white tea by optimized ultrasound-assisted extraction-dispersive liquid-liquid microextraction coupled with gas chromatography. J Chromatog A, 1280: 1-8.
Shimada K, Kawarabayashi T, Tanaka A, Fukuda D, Nakamura Y, Yoshiyama M, Takeuchi K, Sawaki T, Hosoda K, Yoshikawa J. 2004. Oolong tea increases plasma adiponectin levels and low-density lipoprotein particle size in patients with coronary artery disease. Diabetes Res Clin Prac, 65: 227-234.
Şahin H, Özdemir F. 2006. Yeşil çayın sağlık üzerine etkisi. Türkiye 9. Gıda Kongresi; 24-26 Mayıs 2006, Bolu, 219- 222.
Tan LC, Koh W-P, Yuan J-M, Wang R, Au W-L, Tan JH, Tan E-K, Yu MC. 2008. Differential effects of black versus green tea on risk of parkinsons disease in the Singapore Chinese health study. Am J Epidemiol, 167: 553-560.
Tanaka K, Miyake Y, Fukushima W, Sasaki S, Kiyohara C, Tsuboi Y, Yamada T, Oeda T, Miki T, Kawamura N, Sakae N, Fukuyama H, Hirota Y, Nagai M. 2011. Intake of Japanese and Chinese teas reduces risk of Parkinsons disease. Parkinsonism and Related Disorders, 17: 446-450.
Villaño D, Lettieri-Barbato D, Guadagni F, Schmid M, Serafini M. 2012. Effect of acute consumption of oolong tea on antioxidant parameters in healthy individuals. Food Chem, 132: 2102-2106.
Wang K, Liu F, Liu Z, Huang J, Xu Z, Li Y, Chen J, Gong Y, Yang X. 2010. Analysis of chemical components in Oolong tea in relation to perceived quality. Int J Food Sci Tech, 45: 913-920.
Wang Y, Li Q, Wang Q, Li Y, Ling J, Liu L, Chen X, Bi K. 2012. Simultaneous determination of seven bioactive components in oolong tea Camellia sinensis: quality control by chemical composition and HPLC fingerprints. J Agric Food Chem, 60: 256-260.
Wu C, Xu H, Héritier J, Andlauer W. 2012. Determination of catechins and flavonol glycosides in Chinese tea varieties. Food Chem, 132: 144-149.
Xie B, Shi H, Chen Q, Ho CT. 1993. Antioxidant properties of fractions and polyphenol constituents from green, oolong and black teas. Proc Natl Sci Counc Repub China B, 17: 77- 84.
Yamamoto MM, Kawahara H, Matsuda N, Nesumi K, Sano M, Tsuji K, Kawakami Y, Kawakami T. 1998. Effects of tea infusions of various varieties or different manufacturing types on inhibition of mouse mast cell activation. Biosci Biotechnol Biochem, 62: 2277-2279.
Yang YC, Lu FH, Wu JS, Wu CH, Chang CJ. 2004. The protective effect of habitual tea consumption on hypertension. Arch Int Med, 164: 1534-1540.
Yen GC, Chen HY. 1996. Relationship between antimutagenic activity and major composition of various teas. Mutagenesis, 11: 37-41.
Zhao M, Ma Y, Dai LL, Zhang DL, Li JH, Y WX, Li YL, Zhou HJ. 2013. A high-performance liquid chromatographic method for simultaneous determination of 21 free amino acids in tea. Food Anal Methods, 6: 69-75.
Zhu QY, Hackman RM, Ensunsa JL, Holt RR, Keen CL. 2002. Antioxidative activities of oolong tea. J Agric Food Chem, 50: 6929-6934.