The Chelating Effect of Black Tea Extract on Metals

Subject Areas : Microbiology

Z.  Nazari ¹ (دانش آموخته کارشناسی ارشد علوم و صنایع غذایی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران)
M.  Gharachorloo ² (دانشیار گروه علوم و صنایع غذایی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران)
A. H.  Elhamirad ³ (استادیار گروه علوم و صنایع غذایی، واحد سبزوار، دانشگاه آزاد اسلامی، تهران، ایران)

Received: 2017-09-05 Accepted : 2017-09-05 Published : 2017-09-23

Keywords: Chealating Agent, Edible Oils, Tea Extract, Tannic Acid,

Abstract :

Introduction: The oxidation process in oils and fats and the speed of oxidation to someextent depends on the presence of prooxidants namely metals. The application of chelatingagents namely citric acid among others can retard this process. In this study the chelatingeffect of tea extract, tannic acid and citric acid are evaluated and compared to each other.Materials and Methods: Copper in the organic form at the concentration of 0.1 ppm wereadded to tallow, sunflower seed, canola and olive oils and then by the addition of 0.01% citricacid, 0.01% tannic acid and 0.1% tea extract the effect of chelation concerned with each oilhas been evaluated.Results: The results indicated that all the chemicals (citric and tannic acids) and tea extractadded have chelating effect on copper and increased the induction period of the oilsconcerned.Conclusion: It was concluded that tannic acid followed by tea extract and citric acid had thebest chelating effect on copper.

References:

بی نام. (1375). روش های اندازه گیری پایداری روغن­ها و چربی های خوراکی در برابر اکسید شدن. موسسه استاندارد و تحقیقات صنعتی ایران. استاندارد شماره 3734.

قراچورلو، م.، قوامی، م. و آبرومند. پ. (1384). ارزیابی کیفیت تالوی ایران به عنوان یک منبع چربی خوراکی. مجله علمی- پژوهشی علوم کشاورزی- سال یازدهم، شماره 3 ص. 21-29.

Alexandropoulou, I., Komaitis, M. & Kapsokefalou, M. (2006). Effects of iron, ascorbate, meat and casein on the antioxidant capacity of green tea under conditions of in vitro digestion. Food Chemistry, Vol. 94: 359-365.

Boadi, D. K. & Neufeld, R. J. (2001). Encapsulation of tannase for the hydrolysis of tea tannins. Enzyme and Microbial Technology, 28, 590-595.

 

Caragay, A. B. (1992). Cancer preventive foods and ingredients. Food Technol., 45, 65.

Firestone, D. (1994). Official Methods & Recommended practices of the American Oil Chemists Society, 4th edn., AOCS press, Champaign, IL.

Gallaher, R. N., Gallaher, K., Marshall, A. J. & Marshall, A. C. (2006). Mineral analysis of ten types of commercially available tea. Journal of Food Composition and Analysis, 19, S53-S57.

Jeffery, G. H. & Bassett, J. (1989). Vogels Text Book of Quantitative Chemical Analysis, Revised by the following members of the school of chemistry thames polytechnic London, pp: 444-445.

Lawkia, S. (1994). A review on the use of citric acid in the processing of oils and fats. Oleagineux, 39:84-104.

Mai, J. & Chambers, L. J. (1990). Process for inhibiting liquid oxidation in food. US Patent No. 4891231.

Robertson, A. (1992). The chemistry and biochemistry of black tea production the non-volatiles, in tea: cultivation to consumption ed by Wilson, K. and Cliford, M.N., Vhampan and Hull, London,pp 555-600.

Rossell, J. B. (1988). Fats and fatty foods. In Food industries manual. Ranken, M.D., eds, Blackie and son Ltd, London, pp 168-215.

Tink, N. (2007). Spectrophotometric determination content of various Turkish black samples. International Journal of Food Science and Nutrition, 52:3.

Williams, G. M., Wang, C. X. & Latropoulos, M. J. (1990). Toxicity studies of BHA and BHT. 11. Chronic feeding studies. Food Chem. Toxicology, 28:799-806.