| Zearalenone(ZEN) is an estrogenic mycotoxin produced by numerous Fusarium species,such as Fusarium culmorum,Fusarium graminearum and so on.Its toxicological risks for human and animals can arise from direct contamination of grains,wheat,barley, oats,and maize etc.,and processed commercial feed.Because of its toxicity effects on the reproductive and up growth system,immunity system and tumour,ZEN potentially do harm to animals and human.Irradiation for food is a kind of physics' processing,as using infrared ray in electromagnetic waves for caking food,and heating food using microwave. Using 60Co irradiate food,food as a matrix absorpt some energe from ionization irradiate ray.Nowadays,food irradiation usually usingγray by 60Co and 187Cs,the technology has many good quality,as un-irradiation residual,hadro-strength of penetration and by-controlled.The optimum of extracting for sample,setting high performance liquid chromatography method and mass spectrometry method for determining concentration ZEN in samples.The experiment extracted refer to the method of GB/T 19540-2004,then the sample was cleaned up through Oasis HLB column.Extracted samples were analyzed by HPLC on an agilent extent C18 column;with acetonitrile / water(45:50) as mobile phase(1.0 mL min-1) and fluorescence detection(λex =235 nm,λem =460 nm).The calibration graphs were linear up from 12μg/kg～2400μg/kg for ZEN in maize and correlation coefficient was 0.9994.For samples adding the high,middle and low three levels,the recoveries for spiked with ZEN respectively is between 86.240%and 96.736%. The relative standard deviations were 1%～10%.The lowest quantitation limit was 10μg/kg.The MS method using End System Identifier,apparatus' precision in day for different concentration(1 200μg/kg,480μg/kg and 120μg/kg) is 0.7%,1.2%and 2%, respectively;The apparatus' precision between days is 1.8%,2.1%and 1.9%, respectively.Usingγray by 60Co irradiate corn power contaminated by ZEN,choosing different dose,researching how degradation rate correlate to irradiate dose,and find some result, that is degradation rate of ZEN in corn power become higher,as the increasing of irradiating dose;The degradation rate of ZEN is 74.9%,when irradiating dose is 18 kGy; Further studying factors for influents degradation rate of ZEN in corn power,the results are,this factors order is,original concentration of ZEN,water content in corn power, surrounding of irradiation;And studying different appearance of corn influent degradation rate significantly,and degradation rate of ZEN of integral appearance corn is the best,The degradation rate of ZEN is 94.1%,when irradiating dose is 10 kGy;This experiment researching the change of corn' quality after irradiating processing,the results are,the content of crudefat,crudefiber,crudeprotein and water in corn unsignificantly change after irradiating.The degradation trend of ZEN in aqueous solution by gamma ray radiation and the radiolysis products were studied.Qualitative analysis of radiolysis products was conducted using HPLC-MS.It was found that,after irradiation,more than many radiolysis products were found and the response value were low at 218 nm.3 radiolysis products which can be detected in several different radiolysis conditions with high response([M+]:97.0,226.9, 240.9) were focused and conducted initial structural analysis.
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