| Food irradiation technology is widely used in food processing as one of the non-thermalsterilization technologies. Cobalt gamma rays and electron beam (radiation energy under10Mev) arethe two main methods used for food irradiation processing at present. The studies of cobalt gamma raysin food irradiation were earlier and more widely than the studies of eclecton beam in China. Theadvantages of electron beam irradiation on safety, controlling and irradiation effects were more andmore as the development of eclectron accelerator equipment compared with cobalt gamma rays. So theelectron beam irradiation was used more and more in food processing. The studies on features andadvantages of electron accelerator beam and cobalt gamma rays should be done to spread and improvethe implementation of electron accelerator beam in food processing. The studies were mainly on:differences in food sterilization effect, extent of oxidation, effects on nutrition and senses. The studieson differences of food irradiation sterilization were much more thoroughly at present, while the otherswere seldom reported.The differences of cobalt gamma rays and electron beam irradiation on extent of oxidation, qualityof nutrition, physical and chemical properties, senses and flavors were studied using fresh meat asmaterials. The main contents and results of the studies were showed as following:(1) The differences of extent of oxidation between electron beam irradiation and cobalt gammarays were studied. Results showed that the two rays can significantly improve the TBARS value offresh meat, and the value increased as the increasing of dose and storage time. At the same time, theelectron beam treatment TBARS value is lower than the cobalt treatment group. Peroxide value rosefirst and then decreased. Significant effect on PV value was found under cobalt gamma rays irradiationwhich led to severe oxidation. Double thin peak values appeared earlier under cobalt gamma raysirradiation, also the oxidation of system wasstronger. But higher values change of double dilute wasfound under electron beam processing. The electron beam was reducing, but the cobalt gamma ray not.Overall, the oxidation of the electron beam irradiation system of chilled meat is lower than the cobaltgamma ray treatment.(2) The effects of gamma-ray irradiation and electron beam irradiation on crude protein, crude fat,amino acids and other nutritional index of cold fresh meat were studied. The results showed that theelectron beam under10.5kGy didn’t affect the cold fresh meat moisture content, fat content, proteincontent, ash content. No significant effects of cold fresh meat moisture, fat, ash content were found incobalt gamma rays treatment under9.8kGy. Amino acid content under4kGy electron beam processinggroup was higher than other treatment groups.(3) The pH, chromaticity, and microstructure under Scanning Electron Microscopy (SEM) of freshmeat under the two kind of irraditations were sutdied. The results showed that irradiation treatment had a certain influence on cold fresh meat pH which inhibited the increasing of pH. Both irradiationtreatments affected the microstructure of chilled meat, but electron beam had more effect. Irradiationdidn’t affect the cold fresh meat tenderness, quality and structure.(4) The influence of flavor and senses of freash meat under cobalt gamma-ray irradiation andelectron beam irradiation were studied. The quality of the electron beam processing was a little poorerthan the cobalt gamma ray. After6.2kGy electron beam processing, cold fresh meat produced apleasant smell. The chromaticity of3.8,6.2kGy electron groups were stabler during the storage period.The change of flavor under electron beam irradiation of cold fresh meat was slighter than cobaltgamma-ray irradiation. |
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