1、BRITISH STANDARD BS EN 14109:2003 Fat and oil derivatives Fatty Acid Methyl Esters (FAME) Determination of potassium content by atomic absorption spectrometry The European Standard EN 14109:2003 has the status of a British Standard ICS 67.200.10 BS EN 14109:2003 This British Standard was published u
2、nder the authority of the Standards Policy and Strategy Committee on 15 May 2003 BSI 15 May 2003 ISBN 0 580 41841 3 National foreword This British Standard is the official English language version of EN 14109:2003. The UK participation in its preparation was entrusted to Technical Committee AW/307,
3、Oilseeds animal present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprise
4、s 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 document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN14109
5、April2003 ICS67.200.10 Englishversion FatandoilderivativesFattyAcidMethylEsters(FAME) Determinationofpotassiumcontentbyatomicabsorption spectrometry ProduitsdrivsdescorpsgrasEstersmthyliques dacidesgras(EMAG)Dterminationdelateneuren potassiumparspectromtriedabsorptionatomique Erzeugnisseauspflanzlic
6、henundtierischenFettenund lenFettsureMethylester(FAME)Bestimmungdes KaliumgehaltesdurchAtomabsorptionsspektrometrie ThisEuropeanStandardwasapprovedbyCENon2January2003. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusof
7、anationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation under
8、theresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Port
9、ugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN
10、14109:2003EEN14109:2003(E) 2 Foreword Thisdocument(EN14109:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC307“Oilseeds,vegetable andanimalfatsandoilsandtheirbyproductsMethodsofsamplingandanalysis“,thesecretariatofwhichisheld byAFNOR. ThisEuropeanStandard shallbegiventhestatusofanationalstandard,eithe
11、rbypublicationofanidenticaltextor byendorsement,atthelatestbyOctober2003,andconflictingnationalstandardsshallbewithdrawnatthelatest byOctober2003. ThisdocumenthasbeenpreparedunderMandateM/245onFattyAcidMethylester(FAME)giventoCENbythe EuropeanCommissionandtheEuropeanFreeTradeAssociation,andsupportse
12、ssentialrequirementsofEU Directive(s).AnnexAisinformative. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,
13、Luxembourg,Malta,Netherlands,Norway,Portugal, Slovakia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.EN14109:2003(E) 3 1Scope ThisEuropeanStandardspecifiesamethodforthedeterminationofpotassiumcontentsequaltoorgreaterthan 0,5mg/kg. Thismethodisapplicabletofattyacidmethylestersintendedforadditiontominer
14、aloils. WARNINGTheuseofthismethodmayinvolvehazardousequipment,materialsandoperations.This methoddoesnotpurporttoaddresstoallofthesafetyproblemsassociatedwithitsuse,butitisthe responsibilityoftheusertosearchandestablishappropriatesafetyandhealthpracticesanddetermine theapplicabilityofregulatorylimita
15、tionspriortouse. 2Principle Thevegetableoilmethylestersampleisdilutedwithaxylenesolutionandastabilizer. Thepotassiumcontentinthesampleisdirectlydeterminedbyflameatomicabsorptionspectrometryatthe wavelengthof766,5nm.Thecalibrationsolutionsusedarepreparedfromapotassiumorganometallicsalt dissolvedinami
16、xtureofxyleneandstabilizer.Theadditionofastabilizertothecalibrationsolutionsisnecessary inordertoimprovetheirstorage(thelowelementcontentsareunstable)andthelinearityofthecalibration. WARNINGTheestersampleshallbedilutedatleasttentimeswithxylenesothatthecomparisonofthe measurementsofthesamplesolutiona
17、ndstandardsisvalid. NOTE Xylenecanbereplacedbycyclohexaneorlightpetroleuminthoselaboratorieswhicharenotauthorizedtouse aromaticsolvents. 3Reagents Useonlyreagentsofrecognizedanalyticalgrade,unlessotherwisespecified. 3.1 Recommendationsforwashingglassware Theglasswareusedforthepreparationofthesolutio
18、nsshallbewashedatleasttwicewithanapproximate5mol/l solutionofhydrochloricacid,rinsedwithdistilledwaterthendriedinordertoavoidpotassiumpollution. 3.2 Xylene,mixtureofisomers. WARNINGInflammableandnoxious. 3.3 Stabilizer,suppliedbyCONOSTAN 1) . 3.4 Stabilizersolution inxylene,100g/l. Diluteina200mlpol
19、ypropylenevolumetricflask,20gofstabilizer(3.3)withxylene.Storethissolutionina polypropylenebottle. 3.5 Potassium,solutioninoil,5000mg/kg. Readytousesolutionofapotassiumorganometallicsaltinstockoil,havingacertifiedtitre 2) . 1) ProductsavailablecommerciallyfromCONOSTANStandard,suppliedbyConostanDivis
20、ion,ContinentalOilCo,Ponca City,OK74601USA. 2) Conostan(seeabove)orSPEXStandardsuppliedbySPEXIndustries,Inc.ChemicalSalesDepartment,3880Park Avenue,Edison,NJ08820USA. ThisinformationisgivenfortheconvenienceofusersofthisEuropeanStandardanddoes notconstituteanendorsementbyCENoftheseproducts .EN14109:2
21、003(E) 4 3.6 Potassium,solutionofintermediarydilutionsforthepreparationofthesetofcalibrationsolutions. 3.6.1 Potassium,solutioninxylene,500mg/l. Weigh,towithin0,001g,approximately2,5gofthepotassiumsolution(3.6)ina25mlvolumetricflaskanddilute tothemarkwithxylene.Thissolutioncanbestoredforamonth. 3.6.
22、2 Potassium,solutioninxylene,5mg/l. Sample,usingapipette,0,50mlofthepotassiumstandardsolution(3.6.1),transferintoa50mlvolumetricflask anddilutetothemarkwithxylene. Prepareanewsolutioneachday. NOTE Thesolutionsofintermediarydilutionsmaybepreparedinglassflasks(thepotassiumpollutionbeingnegligibleat th
23、esecontents). 4Apparatus 4.1 Atomicabsorptionspectrometer Anyatomicabsorptionspectrometermaybeusedprovidedthatitisequippedwith: 4.1.1 Ahollowpotassiumcathodelamp. 4.1.2 Anebulizationsystemsuitedfortheorganicsolutions,ofwhichthematerialsaresolventresistant. 4.1.3 Aburnerheadcapableofbeingusedwithorga
24、nicsolutionsandanairacetyleneflame. 4.2 Balance,withanaccuracyof 1mg. 4.3 Glassware 4.3.1 25mland50mlvolumetricflasks. 4.3.2 0,5mlgraduatedprecisionpipette. 4.4 Polypropyleneware 4.4.1 50mland200mlvolumetricflasks. 4.4.2 5mlpipette. 4.4.3 250mlbottles. 4.4.4 Automaticpipettehavingavariablevolumeof1m
25、lto5ml,fittedwithejectableanddisposable polypropylenetips. 5Procedure WARNING In order to avoid polluting the potassium solutions, it is recommended to prepare all the determinationsolutionsinpolypropyleneflasksandtoconductallthesamplingoperationsusing polypropylenepipettesorpipetteshavingdisposable
26、polypropylenetips.Itishoweverpossibletouse glasswaretakingcleaningprecautionsinordertoavoidpollutionbytheelementsbeinganalysed. 5.1Sampling SamplingisnotpartofthemethodspecifiedinthisEuropeanStandard.Arecommendedsamplingmethodisgiven inENISO55551.EN14109:2003(E) 5 5.2 Preparationofthesample Weightow
27、ithin0,001gapproximately5,0g(mass ming)ofestersampleina50mlvolumetricflask(volume Vinml). Usingapolypropylenepipette,addtotheflask5,0mlofthe100g/lsolutionofstabilizerinthexylene(see3.4)and dilutetothemarkwithxylene. Sampletwotestportionspersample. 5.3 Preparationofthesetofcalibrationsolutions Prepar
28、ethecalibrationssolutionshavingthefollowingpotassiumcontents: mg/l 0,5 mg/l 0,3 mg/l 0,2 mg/l 0,1 Usingavariablevolumeautomaticpipette,transfer1,00ml,2,00ml,3,00mland5,00mlofthe5mg/lpotassium solution(see3.6.2)into50mlvolumetricflasks. Withapolypropylenepipette,addtoeachflask5mlofthe100g/lsolutionof
29、stabilizerinxylene(see3.4)and dilutetothemarkwithxylene. Preparethezeromemberorblanktestinthesamemannerwithoutaddinganypotassiumsolution. Preparethecalibrationsolutionsjustpriortotheirmeasurementonaccountoftheirinstability. 5.4Spectrometric measurements 5.4.1 Preparationofthespectrometer Setthewavel
30、engthat766,5nmandthebandpassat1nm; conducttheaspirationofthe0,3mg/lcalibrationsolutioninordertooptimizethedifferentinstrumentsettings. Seekthemaximumresponseofthesignalbyadjusting: theairacetylenegaseousmixture; theaspirationspeedofthesolution; theburnerposition. conducttheaspirationofthexyleneplace
31、dinapolypropylenebottleinordertosettheinstrumentatzero absorbance. 5.4.2Calibration Conducttheaspirationoftheblank(orzeromember)andcalibrationsolutionsandcarryoutthreemeasurements foreachofthem. Calculateforeachsolutionthearithmeticalmeanofthethreemeasurements. Plotthecalibrationcurvefromthemeansobt
32、ained. Bywayofindication,thevalueoftheopticaldensityobtainedfora0,3mg/lconcentrationisapproximately0,095 andthecurveismoreorlessastraightlinetherangebeingexploited.EN14109:2003(E) 6 5.4.3Samples Conducttheaspirationofthesolutionsofthesamplesandcarryoutthemeasurementsinthesamewayasforthe standards. N
33、OTE Inthecasewherethemeasurementofthesampleexceedsthesetofcalibrationsolutionsgivenin5.3,prepare standardshavinghigherpotassiumcontents,themaximumcontentbeing2mg/l. 6 Expressionofresults Determinethepotassiumcontents c 1 andc 2 inmg/lofthetwotestportionsofthesample,byreferringtothe calibrationcurve.
34、 Calculatethepotassiumcontents C 1 and C 2 ofthesample,expressedinmg/kg,usingtheequation: m V c C = where m isthemass(ingrams)ofthesampletestportion; V isthevolumeofthesamplesolution(inmillilitres). Calculatethemeancontent Cofpotassiuminthesamplefrom C 1 and C 2 . Expresstheresultinmg/kg,totheneares
35、t0,1mg/kg. 7Precision Aninterlaboratorytestorganizedin2000atEuropeanlevelwiththeparticipationof13laboratories,eachhaving carriedouttwodeterminationsoneachsample,gavethestatisticalresultsindicatedinannexA. 7.1Repeatability Theabsolutedifferencebetweentwoindependentsingletestresults,obtainedusingthesa
36、memethodonidentical testmaterialinthesamelaboratorybythesameoperatorusingthesameequipmentwithinashorttimeinterval, shallnotbegreaterthan r=0,3mg/kgmorethanonceoutof20determinations. 7.2Reproducibility Theabsolutedifferencebetweentwosingletestresults,obtainedusingthesamemethodonidenticaltestmaterial
37、indifferentlaboratoriesbydifferentoperatorsusingdifferentequipment,shallnotbegreaterthan: R=0,505X+0,522 morethanonceoutof20determinations.EN14109:2003(E) 7 8 Testreport Thetestreportshallspecify: allinformationnecessaryforthecompleteidentificationofthesample; thesamplingmethodusedifknown; thetestme
38、thodused,withreferencetothisEuropeanstandard; alloperatingdetailsnotspecifiedinthisEuropeanStandard,orregardedasoptional,togetherwithdetailsof anyincidentswhichmayhaveinfluencedthetestresult(s); thetestresult(s)obtained,oriftherepeatabilityhasbeenchecked,thefinalquotedresultobtained.EN14109:2003(E)
39、8 Annex A (informative) Resultsofaninterlaboratorytrial AEuropeancollaborativetestinvolving13laboratoriesin6countrieswascarriedouton5samples: Sample1: FAMEpreparedfrommixtureofsunflowerandrapeseedoils(40:60); Sample2: FAMEpreparedfromrapeseedoil; Sample3: FAMEpreparedfromsunfloweroil; Sample4: FAMEp
40、reparedfrommixtureofsunflowerandrapeseedoils(80:20); Sample5: FAMEpreparedfromrapeseedoil. ThetestwasorganizedbyCENTC307/WG1in2000andtheresultsobtainedweresubjectedtostatistical analysisinaccordancewithENISO42592togivetheprecisiondatashowninTableA.1. TableA.1 S a m p l e 12345 Nofparticipatinglabora
41、tories 13 13 13 13 13 Nofparticipatinglaboratoriesaftereliminatingoutliers 8 11 12 12 12 Meanvalue (mg/kg) 0,15 0,50 5,60 4,42 2,49 Repeatabilitystandarddeviation(mg/kg) 0,13 0,07 0,08 0,09 0,06 Reproducibilitystandarddeviation(mg/kg) 0,14 0,26 1,04 0,92 0,64 Repeatabilitylimit, r (mg/kg) 0,43 0,21
42、0,23 0,28 0,19 Reproducibilitylimit R(mg/kg) 0,45 0,80 3,21 2,83 1,98EN14109:2003(E) 9 Bibliography 1 ENISO5555, AnimalandVegetablefatsandoilsSampling (ISO5555:2001). 2 ENISO4259, PetroleumproductsDeterminationandapplicationofprecisiondatainrelationtomethods oftest(ISO4259:1992/Cor1:1993).BS EN 1410
43、9:2003 BSI 389 Chiswick High Road London W4 4AL BSI British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions British Standards are updated by amendment or revi
