1、BRITISH STANDARD BS EN 14108:2003 Fat and oil derivatives Fatty Acid Methyl Esters (FAME) Determination of sodium content by atomic absorption spectrometry The European Standard EN 14108:2003 has the status of a British Standard ICS 67.200.10 BS EN 14108:2003 This British Standard was published unde
2、r the authority of the Standards Policy and Strategy Committee on 14 May 2003 BSI 14 May 2003 ISBN 0 580 41840 5 National foreword This British Standard is the official English language version of EN 14108:2003. The UK participation in its preparation was entrusted to Technical Committee AW/307, Oil
3、seeds animal and vegetable fats and oils, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may
4、 be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users a
5、re responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, an
6、d keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 9 and a back cover. The BSI copyright notice displayed in this documen
7、t indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN14108 April2003 ICS67.200.10 Englishversion FatandoilderivativesFattyAcidMethylEsters(FAME) Determinationofsodiumcontentbyatomicabsorption spectro
8、metry ProduitsdrivsdescorpsgrasEstersmthyliques dacidesgras(EMAG)Dterminationdelateneuren sodiumparspectromtriedabsorptionatomique ErzeugnisseauspflanzlichenundtierischenFettenund lenFettsureMethylester(FAME)Bestimmungdes NatriumgehaltesdurchAtomabsorptionsspektrometrie ThisEuropeanStandardwasapprov
9、edbyCENon2January2003. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheMa
10、nagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationals
11、tandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNOR
12、MUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN14108:2003EEN14108:2003(E) 2 Foreword Thisdocument(EN14108:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC307“Oilseeds,vegetable andanimalfatsando
13、ilsandtheirbyproductsMethodsofsamplingandanalysis“,thesecretariatofwhichisheld byAFNOR. This EuropeanStandard shallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyOctober2003andconflictingnationalstandardsshallbewithdrawnatthelatestby October2003
14、. ThisdocumenthasbeenpreparedunderMandateM/245onFattyAcidMethylester(FAME)giventoCENbythe EuropeanCommissionandtheEuropeanFreeTradeAssociation,andsupportsessentialrequirementsofEU Directive(s). AnnexAisinformative. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefo
15、llowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal, Slovakia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.EN14108:2003(E) 3 1Scope ThisEuropeanstandard
16、specifiesamethodforthedeterminationofsodiumcontentsequaltoorgreaterthan 1mg/kg. Thismethodisapplicabletofattyacidmethylestersintendedforadditiontomineraloils. WARNINGTheuseofthismethodmayinvolvehazardousequipment,materialsandoperations.This methoddoesnotpurporttoaddresstoallofthesafetyproblemsassoci
17、atedwithitsuse,butitisthe responsibilityoftheusertosearchandestablishappropriatesafetyandhealthpracticesanddetermine theapplicabilityofregulatorylimitationspriortouse. 2Principle Thevegetableoilmethylestersampleisdilutedwithaxylenesolution. Thesodiumcontentinthesampleisdirectlydeterminedbyflameatomi
18、cabsorptionspectrometryatthe wavelengthof589nm.Thecalibrationsolutionsusedarepreparedfromasodiumorganometallicsaltdissolvedin amixtureofxyleneandstockoil.Theadditionofstockoiltothecalibrationsolutionsisnecessaryinorderto improvetheirstorage(thelowelementcontentsareunstable)andthelinearityofthecalibr
19、ation. WARNINGTheestersampleshallbedilutedatleast25timeswithxylenesothatthecomparisonofthe measurementsofthesamplesolutionandstandardsisvalid. NOTE Xylenecanbereplacedbycyclohexaneorlightpetroleuminthoselaboratoriesthatarenotauthorizedtouse aromaticsolvents. 3Reagents Useonlyreagentsofrecognisedanal
20、yticalgrade,unlessotherwisespecified. 3.1 Recommendationsforwashingglassware Theglasswareusedforthepreparationofthesolutionsshallbewashedatleasttwicewithanapproximate5mol/l solutionofhydrochloricacid,rinsedwithdistilledwaterthendriedinordertoavoidsodiumpollution. 3.2 Xylene(mixtureofisomers) WARNING
21、Inflammableandnoxious. 3.3 Stockoil75 (75mm 2 /s) 1) 3.4 Stockoilsolution inxylene(200g/l);diluteina200mlvolumetricflask,40gofstockoil(3.3)withxylene. Storethissolutioninapolypropylenebottle. 3.5 Sodium,solutioninoil(5000mg/kg) 1) .Readytousesolutionofasodiumorganometallicsaltinstockoil, havingacert
22、ifiedtitre. 3.6 Sodium,solutionsofintermediarydilutionsforthepreparationofthesetofcalibrationsolutions. 1) ProductsavailablecommerciallyfromCONOSTANStandard,suppliedbyConostanDivision,ContinentalOilCo,Ponca City,OK74601USA. SPEXStandardsuppliedbySPEXIndustries,Inc.ChemicalSalesDepartment,3880ParkAve
23、nue,Edison,NJ08820USA. ThisinformationisgivenfortheconvenienceofusersofthisEuropeanStandardanddoesnotconstituteanendorsementby CENoftheseproducts .EN14108:2003(E) 4 3.6.1 Sodium,solutioninxylene(500mg/l):weigh,towithin0,001g,approximately2,5gofthesodiumsolution (3.5)ina25mlvolumetricflaskanddiluteto
24、themarkwithxylene. Thissolutionmaybestoredforamonth. 3.6.2 Sodium,solutioninxylene(5mg/l):sample,usingapipette,0,50mlofthesodiumstandardsolution (3.6.1),transferintoa50mlvolumetricflaskanddilutetothemarkwithxylene. Prepareanewsolutioneachday. NOTE Thesolutionsofintermediarydilutionsmaybepreparedingl
25、assflasks(thesodiumpollutionbeingnegligibleat thesecontents). 4Apparatus 4.1 Atomicabsorptionspectrometer Anyatomicabsorptionspectrometermaybeusedprovidedthatitisequippedwith: 4.1.1 Ahollowsodiumcathodelamp. 4.1.2 Anebulizationsystemsuitedfortheorganicsolutions,ofwhichthematerialsaresolventresistant
26、. 4.1.3 Aburnerheadcapableofbeingusedwithorganicsolutionsandanairacetyleneflame. 4.2 Balance,withanaccuracyof1mg. 4.3 Glassware 4.3.1 25mland50mlvolumetricflasks. 4.3.2 0,5mlgraduatedprecisionpipette. 4.4 Polypropyleneware 4.4.1 50mland200mlvolumetricflasks. 4.4.2 10mlpipette. 4.4.3 250mlbottles 4.4
27、.4 Automaticpipettehavingavariablevolumeof1mlto5ml,fittedwithejectableanddisposable polypropylenetips. 5Procedure WARNING In order to avoid polluting the sodium solutions, it is recommended to prepare all the determinationsolutionsinpolypropyleneflasksandtoconductallthesamplingoperationsusing polypr
28、opylenepipettesorpipetteshavingdisposablepolypropylenetips.Itishoweverpossibletouse glasswaretakingcleaningprecautionsinordertoavoidpollutionbytheelementsbeinganalysed. 5.1Sampling SamplingisnotpartofthemethodspacifiedinthisEuropeanStandard.Arecommendedsamplingmethodisgiven inENISO55551.EN14108:2003
29、(E) 5 5.2 Preparationofthesample 5.2.1 Weightowithin0,001gapproximately2g(massming)ofestersampleina50mlvolumetricflask (volume Vinml)anddilutetothemarkwithxylene. 5.2.2 Sampletwotestportionspersample. 5.3 Preparationofthesetofcalibrationsolutions 5.3.1 Preparethecalibrationssolutionshavingthefollowi
30、ngsodiumcontents: 0,1mg/l0,2mg/l0,3mg/l. 5.3.2 Usingavariablevolumeautomaticpipette,transfer1,00ml,2,00mland3,00mlofthe5mg/lsodium solution(3.6.2)into50mlvolumetricflasks. 5.3.3 Withapolypropylenepipette,addtoeachflask10mlofthe200g/lsolutionofstockoilinxylene(3.4)and dilutetothemarkwithxylene. 5.3.4
31、 Preparethezeromemberorblanktestinthesamemannerwithoutaddinganysodiumsolution. 5.3.5 Preparethecalibrationsolutionsjustpriortotheirmeasurementonaccountoftheirinstability. 5.4Spectrometric measurements 5.4.1 Preparationofthespectrometer Setthewavelengthat589,0nmandthebandpassat0,5nm; conducttheaspira
32、tionofthe0,3mg/lcalibrationsolutioninordertooptimizethedifferentinstrumentsettings. Seekthemaximumresponseofthesignalbyadjusting: theairacetylenegaseousmixture; theaspirationspeedofthesolution; theburnerposition. conducttheaspirationofthexyleneplacedinapolypropylenebottleinordertosettheinstrumentatz
33、ero absorbance. 5.4.2Calibration Conducttheaspirationoftheblank(orzeromember)andcalibrationsolutionsandcarryoutthreemeasurements foreachofthem. Calculateforeachsolutionthearithmeticalmeanofthethreemeasurements. Plotthecalibrationcurvefromthemeansobtained. Bywayofindication,thevalueoftheopticaldensit
34、yobtainedfora0,3mg/lconcentrationisapproximately0,290 andthecurveismoreorlessastraightlineintherangeconsidered. 5.4.3Samples Conducttheaspirationofthesolutionsofthesamplesandcarryoutthemeasurementsinthesamewayasforthe standards.EN14108:2003(E) 6 NOTE Inthecasewherethemeasurementofthesampleexceedsthe
35、setofcalibrationsolutionsgivenin5.3,prepare standardshavinghighersodiumcontents,themaximumcontentbeing1mg/l. 6 Expressionofresults Determinethesodiumcontentsc 1 andc 2 inmg/lofthetwotestportionsofthesample,byreferringtothe calibrationcurve. Calculatethesodiumcontents C 1 and C 2 ofthesample,expresse
36、dinmg/kg,usingtheequation: m V c C = where m isthemass(ingrams)ofthesampletestportion; V isthevolumeofthesamplesolution(inmillilitres). Calculatethemeancontent Cofsodiuminthesamplefrom C 1 and C 2 . Expresstheresultinmg/kg,tothenearest0,1mg/kg. 7Precision Aninterlaboratorytestorganizedin2000atEurope
37、anlevelwiththeparticipationof13laboratories,eachhaving carriedouttwodeterminationsoneachsample,gavethestatisticalresultsindicatedinannexA. 7.1Repeatability Theabsolutedifferencebetweentwoindependentsingletestresults,obtainedusingthesamemethodonidentical testmaterialinthesamelaboratorybythesameoperat
38、orusingthesameequipmentwithinashorttimeinterval, shallnotbegreaterthan: r=0,086X+0,242 morethanonceoutof20determinations. 7.2Reproducibility Theabsolutedifferencebetweentwosingletestresults,obtainedusingthesamemethodonidenticaltestmaterial indifferentlaboratoriesbydifferentoperatorsusingdifferentequ
39、ipment,shallnotbegreaterthan: R=0,263X+1,355 morethanonceoutof20determinations. 8 Testreport Thetestreportshallspecify: allinformationnecessaryforthecompleteidentificationofthesample; thesamplingmethodusedifknown; thetestmethodused,withreferencetothisEuropeanstandard;EN14108:2003(E) 7 alloperatingde
40、tailsnotspecifiedinthisEuropeanStandard,orregardedasoptional,togetherwithdetailsof anyincidentswhichmayhaveinfluencedthetestresult(s); thetestresult(s)obtained,oriftherepeatabilityhasbeenchecked,thefinalquotedresultobtained.EN14108:2003(E) 8 Annex A (informative) Resultsofaninterlaboratorytrial Resu
41、ltsofaninterlaboratorytrial. AEuropeancollaborativetestinvolving13laboratoriesin6countrieswascarriedouton5samples: Sample1: FAMEpreparedfromrapeseedoil; Sample2: FAMEpreparedfromsunfloweroil; Sample3: FAMEpreparedfromamixtureofrapeseedandsunfloweroils(80:20); Sample4: FAMEpreparedfromamixtureofrapes
42、eedandsunfloweroils(60:40); Sample5: FAMEpreparedfromrapeseedoil. ThetestwasorganizedbyCENTC307/WG1in2000andtheresultsobtainedweresubjectedtostatistical analysisinaccordancewithENISO42592togivetheprecisiondatashowninTableA.1. TableA.1Sodiumcontent S a m p l e 12345 Nofparticipatinglaboratories 13 13
43、 13 13 13 Nofparticipatinglaboratoriesaftereliminatingoutliers 13 12 13 12 12 Meanvalue (mg/kg) 4,96 1,14 3,14 1,00 3,01 Repeatabilitystandarddeviation(mg/kg) 0,23 0,10 0,21 0,13 0,11 Reproducibilitystandarddeviation(mg/kg) 0,88 0,53 0,69 0,54 0,69 Repeatabilitylimit, r(mg/kg) 0,70 0,32 0,64 0,39 0,32 Reproducibilitylimit R(mg/kg) 2,70 1,64 2,10 1,67 2,13EN14108:2003(E) 9 Bibliography 1 ENISO5555, AnimalandVegetabl
