1、STD-BSI BS EN L7Ab-ENGL 1997 Lb24bb7 Ob2705b bTb W BRITISH STANDARD Detection of irradiated food containing bone - Method by ESR spectroscopy * cn * The European Standard EN 1786 : 1996 has the status of a British Standard ICs 67.040 BS EN 1786 : 1997 PYRIGHT LAW _ STD*BSI BS EN 178b-ENGL 1997 Lb24b
2、b7 Ob27057 532 = AmdNo. BS EN 1786 : 1997 Date Textaffectd This British Standard, having been prepared under the direction of the Consumer Products and Services Sector Board, was published under the authority of the Standards Board and comes into effect on 16 June 1997 Q BSI 1997 The foiiowing BSI r
3、eferences relate to the work on this standard commiaee reference AWf43 Draft for comment 9W500044 DC ISBN O 680 27442 X Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technid Panel AW/J3, Food analysis - Horizontal methods, upon which the f
4、oiowing bodies were represented: Association of public Analysts Food and Drink Federation institute of Food Science and khnology Laboratory of the Government Chemist Minishy of Agrcuture Fisheries and Food Royal Society of Chemistry STD*BSI BS EN 178b-ENGL 1777 = lb24bb7 0b271158 Y77 BS EN 1786 : 19
5、97 Contents page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN 1786 3 O BSI 1997 i STD-BSI BS EN 17b-ENGL 1777 m Lb24bb9 Ob27059 305 m BS EN 1786 : 1997 National foreword This British Standard has been prepared under the direction of Technid Panel AWM3 and is t
6、he English language version of EN 1786 : 1996 Fmdstqffs - DetectZon of irradiated food containing bone - Method by ESR spectroscopy, published by the European Committee for Standardization (CEN). EN 1786 was produced as a result of international discussions in which the United Khgdom took an active
7、park Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a fiont cover, an inside hnt cover, pages i and ii, the EN title page, pages 2 to 10, an inside back cover and a back cover. ii O BSI 1997 STD-BSI BS EN 178b-EN
8、GL la797 1b2LibbS Ob27b0 027 = EUROPEAN STANDARD EN 17% NORME EUROPENNE EUROP- NORM December 1996 ICs 67.020 Descriptors: Foodtstuffs, irradiated foodstuffs, ionizing radiation, food analysis, detection of inwliation treatment, meat bones, fish bones, ESR-spectroscopy Engltsh version I?- Detection o
9、f irradiated food contauning bone - Method by ESR spectsoscopy produits alimentaires - Dtection daliments ioniss contenant des os ou des art - Mthode par spectroscopie WE Lebensmitel - Nachweis von besh.ahlten hoche sweep width 5 mT to 20 mT 50 IZHZ or 100 kHz modulation frvencx 0,2 mT up to 0,4 mT
10、modulation amplitude; 50 ms to 200 ms time constanl?); sweep rate3) 2,5 mT.min-l to 10 mT.min-l or accumulalion of 3 to 5 spectra at greater sweep rate and shorter time constanc between about 1,0 X lo5 and Gain: Temperature room temperature. l,o x 106; 6.2.2 Andusis of sample Nyse the sample prepare
11、d as described in 6.1 in an ESR tube (4.3). Although the g value of the individual signais of the ESR spectrum does not need to be determjned in most cases, it can be used for positive identification of irradiated samples (see 7.2). I. 7 Evaluation 7.1 Assessment of the ESR spectra hmdiakd samples a
12、re recognized by the appearance of a typid asymmetric signal having g values of 2,002 and 1,998 (see 7.2). This signal is atributed to trapped radicals in hydroxyapatite produced by the action of ionizing radiation on the bone. A low intensity symmetrical signai having a g value of gsymm = 2,005 (se
13、e gure Al) is sometimes present in the ESR spectra (e.g. in the case of bones containing marrOW). ?5picai examples of ESR spectra of unirradiated and hmdiaed bones (chicken thigh in this case) are shown in the gures Al, A2 and A3. Note that the ESR spectra of bones irradiated at relatively low doses
14、 (less than 2 kGy to 3 kGy) frequently reveal a combination of the radiation-specific and the non-specific signal (see figure A2). At doses less than 0,5 kGy, the non-specific signai may be stronger than the spec if one. In contrast, the radiation-specific signal is frequently the only one observed
15、(see gure k3) in the case of high doses (more than 3 my). 7.2 Calculation of the g value Using the measured values obtained as described in 6.2.2, CAC is the magnetic field (magnetic flux density), in millitesla (mT) (10 Gauss = 10 Os = 1 mT). The procedure for calculating the g value of the signais
16、 from bone is to measure the hquency (e.g. frequency counter) and the field B (e.g. gaussmeter) at the positions of the arrows in figures Al to A.3. The following values are found in bones: gsymm. = 2,005 f 0,001 (no proof of jrradialion); gi = 2,002 f 0,001 (irradiatRd); 92 = 1,998 f 0,001 (irradia
17、tRd). 8 Limitations Detection of irra b) a reference to this European %anclar c) the result; d) the date of sampling and samping procedure (if known); e) the date of receipt; f) the date of test; g) any paiticular points observed in the course of the test; h) any operations not specined in the metho
18、d or regarded as optional which might have affected the resuits. * m * ) False negatives are irradiated samples identified as unirradated. 1 False positives are unirradiated samples identied as irradiated. 3, The five false negatives were due to misinterpretation of the spectra Table 2. Inter-labora
19、tory data Product No. of samples No. of false negatives) No. of false positives) Chicken bone 108 O O Rout bone 108 O 23) . I l l 1 False negatives are irradiated samples identified as unirradiated. False positives are unirradiated samples identified as irradiakd. I 3, The two false positives were d
20、ue to misinterpretation of the spectra O BSI 1997 Page 6 EN 1786 : 1996 I Annex A (normative) Figures Field: 360 mT f 10 mT (3500 Gs f 100 Gs). Gain: 3,2 X 105. Figure A.l Typical ESR spectrum of an nnirradiated chicken thigh sample Field: 350 mT f 10 mT (3500 Gs * 100 Gs). alli: 3,2 x 105. Figure A
21、.2 Typical ESR spectrum of a chicken thigh sample irradiated with a dose of approximately 1 kGy Field: 350 mT * 10 mT (3500 Gs f 100 Gs). Gain: 1,0 X 105. 92 Figure A.3 Typical ESR spectrum of a chicken thigh sample irradiated with a dose of approximately 3 kGy O BSI 1997 STD-BSI BS EN L7b-ENGL 1797
22、 Lb24bb9 Ub27bb 545 Page 7 EN 1786 : 1996 Annex B (informative) Further Iliformation on the applicability Laboratory experience has been gained to support the application of this method to the following sample types: - bones from meat, including duck, i-og, goose, chicken, hare, lamb, turkex beef an
23、d pork; - bones from fish, including eel, trout, whiting, sardine, hammerhead shark, halibut, he-, cod, salmon, mackerel and cyprins. O BSI 1997 STD-BSI BS EN 178b-ENGL 1997 Lb24bb7 0b27067 48L W Page 8 EN 1786 : 1996 Annex C (informative) Bibliography Helle, N. and Bgi, KW.: Methods for .identimrzg
24、 idiated food. In: Food k., 1990,4,2439. Raffi, J., Evans, J.C., Agnel, J.-P, Rowlands, C.C. and Lesgards, G.: ESR analysis of ZWiatedfrOgs kgs and fzshes. In: AppL Radiat. kat, 1989,4, 1215-1218. Lea, J.S., Dodd, N.J.E and Swallow, AJA Method of testing for irradiation of poultw In: Int J. Food Sci
25、. lchnol., 1988, 23,625632. Desrosiers, M.F. and Sic, M.G.: Postidiation dosimetry of meat by electron spin resomnce spectroscopy of bones. In: J. Agric. Food Chem., 1988,36,601-603. Stevenson, M.H. and Gray, R.: Eflit of irraiation dose, stomge time and temperaturn on the ESR signal in imuihted chi
26、cken bone. In: J. Sci. Food Agric., 1989,48,269-274. Gray, R., Stevenson, M.H. and Kiipahick, D.J.: The eflit of irradiation dose and age of the bid on the ESR sigrmi in irmdhted chichm drumsticks. In: Radiat. Phys. Chem., 1990,36, 284-287. Stevenson, M.H. and Gray, R.: An investigation into the efl
27、ect of sample prepamtion methods on the Goodman, B.A., McPM, D.B. and Duthie, D.M.L., Elecm spin resomnce spectmsc of some irradiated foodsEuffs. In. J. Sci. Food Agric., 1989, 47, 101-111. Untersuchung von Lebemmln: Nmhweis eiw Strahlenbehandlung (ionis.ierende Stmhkn) von Imochenhaltigem Fkisch du
28、rch Messung des ESR ektro-Spin-Res)-Spektrurns (Detection of bone containing meat treuted wih (ionking) radiation by ESR spectroscopy). L 06.00-30. In: Amtliche Sammlung von Untemchungsverfahren nach Q 35 LMBG Vi Methods of sampling and analysis of foods, tobacco products, cosmetics and commodity go
29、oddFederal Health office) Loseblattausgabe, Stand Aug. 1993 Bd 1 (hose leaf edition, as of 199348 Vol. L) Berlin, Kln: Beuth Verlag GmbE Untersuchung von Lebensmitteln Nachweis einer St-kdung (ionisieren Methods of sampling and analysis of foods, tobacco products, cosmetics and commodity gooddFedera
30、l Health office) Loseblaaausgabe, Stand Aug. 1993 Bd. 1 (Loose leaf edition, as of 199348 Vol. I.) Berlin, Kln: Beuth Verlag GmbH. MAFF vaidakd methods for the analysis of foodstuffs, No. V28: Detection of meat containing bone. In: J. Raffi, J., Deiince, H., Marchioni, E., Hasselmann, C., Sjberg, A.
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