Research Articles

Comparison of the mineral composition of leaves and infusions of traditional and herbal teas

Jana Olivier, Elize A. Symington, Cornelia Z. Jonker, Isaac T. Rampedi, Tersia S. van Eeden
South African Journal of Science | Vol 108, No 1/2 | a623 | DOI: https://doi.org/10.4102/sajs.v108i1/2.623 | © 2012 Jana Olivier, Elize A. Symington, Cornelia Z. Jonker, Isaac T. Rampedi, Tersia S. van Eeden | This work is licensed under CC Attribution 4.0
Submitted: 09 February 2011 | Published: 24 January 2012

About the author(s)

Jana Olivier, University of South Africa, South Africa
Elize A. Symington, University of South Africa, South Africa
Cornelia Z. Jonker, University of South Africa, South Africa
Isaac T. Rampedi, University of Johannesburg, South Africa
Tersia S. van Eeden, University of South Africa, South Africa

Abstract

Most research on teas has focused on organic composition and less attention has been given to the mineral composition. The aim of this study was to examine and compare the mineral compositions (Na, Mg, K, Ca, P, S, Fe, Mn, Zn, Cu and Al) of eight commonly consumed teas. The teas included three traditional black or green teas (from Africa, China and Sri Lanka) and five herbal teas – two from South America (maté and coca) and three from South Africa (rooibos, honeybush and Athrixia phylicoides). Analyses were conducted on five samples of dry tea leaves of each of the teas and their infusions (steeping time: 6 min) using identical techniques in inductively coupled plasma optical emission spectrometry (ICP-OES). It was found that each tea has a unique mineral profile. Dry tea leaves and their respective infusions also exhibited different mineral profiles. The tea infusions that contained relatively higher concentrations of beneficial minerals were maté, coca and Athrixia. High levels of aluminium were found in the traditional black and green teas whilst rooibos was high in sodium. Although teas are not rich sources of nutrients, the consumption of maté could contribute significantly to dietary manganese requirements.

Keywords

herbal teas; Athrixia; rooibos; honeybush; Camelia sinensis; minerals; health

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References


Wu CD, Wei G. Tea as a functional food for oral health. Nutr Oral Health. 2002;18(5):443–444.

Hicks A. Review of global tea production and the impact on industry of the Asian economic situation. Bangkok: Food and Agricultural Organization Regional Office for Asia and the Pacific; no date.

Hertog MGL, Feskens EJM, Hollman PCH, et al. Dietary anti–oxidant flavonoids and risk of coronary heart disease: The Zutphen Elderly Study. Lancet. 1993;342:1007–1011. http://dx.doi.org/10.1016/0140-6736(93)92876-U

Yang CS, Wang ZY. Tea and cancer: A review. J Natl Cancer Inst. 1993;58:1038–1049. http://dx.doi.org/10.1093/jnci/85.13.1038

Lukaski HC, Penland JG. Functional changes appropriate for determining mineral element requirements. J Nutr. 1996;126:2354S–2364S. PMid:8811798

Viteri FE, Gonzalez H. Adverse outcomes of poor micronutrient status in childhood and adolescence. Nutri Rev. 2002;60(suppl):S77–S83. http://dx.doi.org/10.1301/00296640260130795

Hicks A. Current status and future development of global tea production and tea products. Au J T. 2009;12(4):251-264.

Cabrera C, Artacho R, Giménez R. Beneficial effects of green tea – A review. J Am Coll Nutr. 2006;25(2):79–99. PMid:16582024

Katiyar SK, Mukhtar H. Tea in chemoprevention of cancer: Epidemiologic and experimental studies (review). Int J Oncol. 1996;8:221–238. PMid:21544351

Geleijnse JM, Launer LJ, Hofman A, et al. Tea flavonoids may protect against atherosclerosis: The Rotterdam Study. Arch Inter Med. 1999;159:2170–2174. http://dx.doi.org/10.1001/archinte.159.18.2170, PMid:10527294

Han LK, Takaku T, Li J, et al. Anti–obesity action of oolong tea. Int J Obes Relat Metab Disord. 1999;23:98–105. http://dx.doi.org/10.1038/sj.ijo.0800766, PMid:10094584

Weisburger JH. Tea and health: The underlying mechanisms. Proc Soc Exp Biol Med. 1999;220:271–275. http://dx.doi.org/10.1046/j.1525-1373.1999.d01-46.x, PMid:10202402

Hegarty VM, May HM, Khaw KT. Tea drinking and bone mineral density in older women. Am J Clin Nutr. 2000;71:1003–1007. PMid:10731510

Sarkar S, Sett P, Chowdhury T, Ganguly DK. Effect of black tea on teeth. J Indian Soc Pedod Prev Dent. 2000;18:139–140. PMid:11601182

Blot WJ, McLaughlin JK, Chow W-H. Cancer rates among drinkers of black tea. Crit Rev Food Sci Nutr. 1997;37:739–760. http://dx.doi.org/10.1080/10408399709527800, PMid:9447273

Mukamal KJ, MacDermott RN, Vinson JA, et al. A 6-month randomized pilot study of black tea and cardiovascular risk factors. Am Heart J. 2007;154:724.e1–724.e6.

Gardner EJ, Ruxton CHS, Leeds AR. Black tea – Helpful or harmful? A review of the evidence. Eur J Clin Nutr. 2007;61(1):3–18. http://dx.doi.org/10.1038/sj.ejcn.1602489, PMid:16855537

Higdon J, Drake VJ, Dashwood RH. Tea [homepage on the Internet]. c2008 [cited 2008 Feb 13]. Available from: http://lpi.oregonstate.edu/infocenter/phytochemicals/tea

Malik J, Szakova J, Drabek O, et al. Determination of certain micro and macroelements in plant stimulants and their infusions. Food Chem. 2008;111:520–525. http://dx.doi.org/10.1016/j.foodchem.2008.04.009

Krewski D, Yokel RA, Nieboer E, et al. Human health risk assessment for aluminium, aluminium oxide, and aluminium hydroxide. J Toxicol Environ Health B Crit Rev. 2007;10(Suppl 1):1–269. http://dx.doi.org/10.1080/10937400701597766, PMid:18085482, PMCid:2782734

Heck CI, De Mejia EG. Yerba mate tea (Ilex paraquariensis): A comprehensive review on chemistry, health implications, and technological considerations. J Food Sci. 2007;72(9):R138–R151. http://dx.doi.org/10.1111/j.1750-3841.2007.00535.x, PMid:18034743

Goldenberg D. Maté: A risk factor for oral and oropharyngeal cancer. Oral Oncol. 2002;38:646–649. http://dx.doi.org/10.1016/S1368-8375(01)00127-0

Bates MN, Hopenhayn C, Rey OA, Moore LE. Bladder cancer and mate consumption in Argentina: A case-control study. Cancer Lett. 2007;246:268–273. http://dx.doi.org/10.1016/j.canlet.2006.03.005, PMid:16616809

De Mejia EG, Song YS, Ramirez-Mares MV, Kobayashi H. Effect of yerba mate (Ilex paraquariensis) tea on topoisomerase inhibition and oral carcinoma cell proliferation. J Agric Food Chem. 2005;53(6):1966–1973.

Encyclopedia: Coca [homepage on the Internet]. c2008 [cited 2008 Feb 26]. Available from: http://www.nationmaster.com/encyclopedia/Coca

Jenkins AJ, Llosa T, Montoya I, Cone EJ. Identification and quantification of alkaloids in coca tea. Forensic Sci Int. 1996;77(3):179–189. http://dx.doi.org/10.1016/0379-0738(95)01860-3

Penny ME, Zavaleta A, Lemay M, et al. Can coca leaves contribute to improving the nutritional status of the Andean population? Food Nutr Bull. 2009;30(3):205–216. PMid:19927600

Van Wyk B-E, Gericke N. People’s plants. Pretoria: BRIZA, 1997; p. 99–100.

Joubert E, Ferreira D. Antioxidants of rooibos tea – A possible explanation of its health promoting properties. S Afr J Food Sci Nutr. 1996;8(3):79–83.

Von Gadow A, Joubert E, Hansmann CF. Comparison of the antioxidant activity of aspalathin with that of other phenols of rooibos tea (Aspalathus linearis), alpha-tocopherol, BHT and BHA. J Agric Food Chem. 1997;45:632–638. http://dx.doi.org/10.1021/jf960281n

Marnewick JL, Joubert E, Swart P, et al. Modulation of hepatic drug metabolising enzymes and oxidative status by unique South African herbal teas, rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia), green and black (Camellia sinensis) teas in rats. J Agric Food Chem. 2003;51:8113–8119. http://dx.doi.org/10.1021/jf0344643, PMid:14690405

Simrany J. The state of the US tea industry. Tea Association of the United States [homepage on the Internet]. c2005 [cited 2007 Nov 16]. Available from: www.teausa.com

Du Toit J, Joubert E, Britz TJ. Honeybush tea – A rediscovered South African herbal tea. J Sustainable Agric. 1998;12:67–84.

Kamara BI, Brand J, Brandt EV, Joubert E. Phenolic metabolites from honeybush tea (Cyclopia subternata). J Agric Food Chem. 2004;52:5391–5395. http://dx.doi.org/10.1021/jf040097z, PMid:15315375

Olivier J, De Jager A. [An ethnobotanical survey of an indigenous South African tea: Athrixia phylicoides]. Suid-Afrikaanse Tydskr Natuurwetenskap Tegnol. 2005;24(4):139–147. Afrikaans.

Rampedi IT, Olivier J. The use and commercial development potential of Athrixia phylicoides: A multipurpose indigenous South African plant. Acta Acad. 2005;37(3):165–183.

Mashimbye MJ, Mudau FN, Soundy P, Van Ree T. A new flavonol from Athrixia phylicoides (bush tea). S Afr J Chem. 2006;59:1–2.

Joubert E, Gelderblom WCA, Louw A, De Beer D. South African herbal teas: Aspalathus linearis, Cyclopia spp. and Athrixia phylicoides – A review. J Ethnopharmacol. 2008;119:376–412.

McGaw LJ, Steenkamp V, Eloff JN. Evaluation of Athrixia (bush tea) for cytotoxicity, antioxidant activity, caffeine content and presence of pyrrholizidine alkaloids. J Ethnopharmacol. 2007;110(1):16–22. http://dx.doi.org/10.1016/j.jep.2006.08.029, PMid:17045437

Statistical Package for the Social Sciences. Version 17.0. Chicago, IL: SPSS Inc.; 2008.

Jansen S, Watanabe T, Dessein S, et al. A comparative study of metal levels in leaves of some Al-accumulating Rubiaceae. Ann Bot. 2003;91(6):657–663. http://dx.doi.org/10.1093/aob/mcg071, PMid:12714364

Fraga CG. Relevance, essentiality and toxicity of trace elements in human health. Mol Aspects Med. 2005;26:235–244. http://dx.doi.org/10.1016/j.mam.2005.07.013, PMid:16125765

Street R, Szakova J, Drabek O, Mladkova L. The status of micronutrients (Cu, Fe, Mn, Zn) in tea and tea infusions in selected samples imported to the Czech Republic. Czech J Food Sci. 2006;24(2):62–71.

Department of Health, South African Government. The National Food Consumption Survey (NFCS): Children aged 1-9 years, South Africa, 1999 [homepage on the Internet]. c2000 [cited 2008 Feb 05]. Available from: http://www.sahealthinfo.org/nutrition/food7tables7-28.pdf

Wróbel K, Wróbel K, Urbina EM. Determination of total aluminium, chromium, copper, iron, manganese, and nickel and their fractions leached to the infusions of black tea, green tea, Hibiscus sabdariffa, and Ilex paraguariensis (mate) by ETA-AAS. Biol Trace Elem Res. 2000;78(1–3):271–280. http://dx.doi.org/10.1385/BTER:78:1-3:271

Bamji NMS, Kaladhar M. Risk of increase aluminium burden in the Indian population: Contribution from aluminium cookware. Food Chem. 2000;70:57–61. http://dx.doi.org/10.1016/S0308-8146(00)00068-6

Mehra A, Baker CL. Leaching and bioavailability of aluminium, copper and manganese from tea (Camellia sinensis). Food Chem. 2007;100(4):1456–1463. http://dx.doi.org/10.1016/j.foodchem.2005.11.038

World Health Organisation (WHO). Sixty-seventh report of the joint FAO/WHO expert committee on food additives. Evaluation of certain food additives and contaminants. WHO Technical Report Series 940. Geneva: WHO; 2007.

Mamba BB, Rietveld LC, Verberk JQJC. SA drinking water standards under the microscope. Water Wheel. 2008;7(1):25–27.

National Academy of Sciences [homepage on the Internet]. c2008 [cited 2008 Feb 05]. Available from: www.iom.edu/



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