The Chelating Effect of Black Tea Extract on Metals

Subject Areas : Microbiology

Z. Nazari ¹ , M. Gharachorloo ² , A. H. Elhamirad ³

1 - دانش آموخته کارشناسی ارشد علوم و صنایع غذایی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران
2 - دانشیار گروه علوم و صنایع غذایی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران
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.

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