Journal of Radiation Research and Radiation Proces ›› 2016, Vol. 34 ›› Issue (3): 30401-030401.doi: 10.11889/j.1000-3436.2016.rrj.34.030401

• RADIATION TECHNOLOGY APPLICATION • Previous Articles    

Identification of irradiated tea by ESR spectroscopy

FEI Chen1, YE Xinjin1, ZHANG Haiwei1, LIANG Jin1, ZHENG Wenjia2   

  1. 1 School of Tea & Food Science and Technology, Anhui Agricultural University, Heifei 230036, China;
    2 Guizhou Tea Science Research Laboratory, Guiyang 550000, China
  • Received:2015-11-24 Revised:2015-12-17 Online:2016-06-20 Published:2016-01-21
  • Supported by:

    Supported by Scientific Research Project of Anhui Province Department of Education (the Provincial Level of Key Projects Fund with the Outstanding Young Talents in Universities and Colleges, 2013SQRL017ZD) and Project of Guizhou Province Tea Processing Technology Innovation Talents Team (Guizhou Branch Talent Team No.[2014]4025)

Abstract:

In order to explore the possibility to identify the irradiated tea by electron spin resonance (ESR), green tea (Huangshan Maofeng Tea) and black tea (Keemun Black Tea) were detected by ESR after irradiation with Co-60 γ-rays. The relations between ESR intensity of the tea samples and absorbed doses as well as storage time were analyzed. It turned out that there was a significant increase of free radicals intensity in all tea samples at low absorbed doses (p<0.01). The relations between the tea ESR intensity and absorbed doses fitted the multinomial growth while the relations between the tea ESR intensity and storage time fitted the power correlation decrease. After storage at room temperature for 70 d, the ESR intensity in irradiated tea decreased to the steady state which was still significantly higher than that in unirradiated tea samples (p<0.01). Therefore, it is possible to use ESR to identify whether the green or black tea was irradiated or not.

Key words: Electron spin resonance (ESR), Irradiation, Free radicals, Tea, Detection

CLC Number: 

  • TS205