經輻射照射處理之黑胡椒的電子順磁共振鑑別方法研究

Research on the identification using EPR method for black pepper processed by radiation irradiation

林建男(Lin, Chein Nan)

指導教授 ： 許靖涵 ； 許芳裕

國立清華大學/原子科學院/生醫工程與環境科學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00268

摘要

中文摘要
游離輻射照射食品可去除微生物、病原體，或可延長蔬果的熟化、抑制發芽，增加食品的保存期限。臺灣已發展食品照射這項技術並實際應用於日常生活中，然而卻尚未建立後續檢測食品是否已受輻射照射之方法。
利用黑胡椒以Co-60射源照射不同劑量後，會產生不同的自由基濃度，再以電子順磁共振(EPR)光譜儀計讀。EPR光譜儀主要量測的對象是自由基內未成對(unpaired)電子，而EPR的信號是來自於電子自旋轉換的電磁能量共振吸收，若EPR訊號越強則表示自由基的濃度高，因此可推估給予的輻射劑量也越大。
本研究證實照射後黑胡椒的EPR訊號會隨著存放時間增加而開始減少，此外，並發現照射後比未照射之黑胡椒有較高的峰對峰值與峰對峰值比值，因此可用峰對峰值與比值來分別黑胡椒是否受照射。最後本研究依照上述結果，訂定出兩種鑑別標準，第一個鑑別標準是以峰對峰值做分別，當黑胡椒經EPR光譜儀計測後，峰對峰值大於此鑑別標準（31496.245），則認定為經游離輻射照射，反之則視為未受游離輻射照射；而另一個鑑別標準是將峰對峰值換算成比值，比較鑑別標準與比值，若比值大於此標準（6.4025），則認定為黑胡椒是經輻射照射。
本研究己建立鑑別系統之雛形，由前述之結果已能觀察出EPR訊號與輻射劑量及存放時間之關係，並建立鑑別值之設定方法。此項檢測技術能夠提供食品照射與否之判斷需求，提升我國食品衛生及安全。
關鍵字：輻射照射食品、電子順磁共振、峰對峰值、峰對峰比值。

關鍵字

輻射照射食品 ； 電子順磁共振 ； 峰對峰值 ； 峰對峰比值

並列摘要

Abstract
Food irradiation can eliminate microbes, pathogens, or extend the ripening and restrain germination of fruits and vegetables. In Taiwan, food irradiation has been developed and used in daily life. However, it has unestablished a way to detect the foodstuff whether been irradiated.
Black pepper irradiated with Co-60 in different doses that would produced free radical in concentration. This signal can be detected by the Electron paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy measures the unpaired electrons of free radicals, and EPR signal is derived from the conversion of electron spin resonance absorption. The stronger EPR signal, the higher concentration of free radicals. The intensity of EPR signal is proportional to radiation dose.
This study proved that the EPR signal strength would decrease with storage time increasing. Besides, the peak-to-peak high and peak-to-peak high ratio of the irradiated black pepper are stronger than the non-irradiated ones. Finally, the study proposes two discriminator values. One is identified by the peak-to-peak high, and the other is identified by the ratio of peak-to-peak high. If peak-to-peak high or the ratio of peak-to-peak high exceeds the discriminator value, black pepper was processed by radiation irradiation.
This study demonstrates the relationship of the EPR signal between radiation dose and storage time from the results, and has preliminarily developed a method to tell non-irradiated and irradiated food apart. This method desires to filter the irradiated food and enhances food safety and sanitation.

Key Word：Food irradiation、Electron paramagnetic resonance、peak-to-peak high、peak-to-peak high ratio.

並列關鍵字

Food irradiation ； Electron paramagnetic resonance ； peak-to-peak high ； peak-to-peak high ratio

參考文獻

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