新鲜肉类水分含量的快速检测低场核磁共振液体核磁共振方法

InternationalStandard

ISO17646

Rapiddetectionofmoisturecontentinfreshmeat—Low-fieldnuclearmagneticresonance

(LF-NMR)method

Firstedition2025-05

Détectionrapidedelateneurenhumiditédanslaviandefraîche—Méthodeparrésonancemagnétiquenucléaireàchampfaible

Referencenumber

ISO17646:2025(en) ©ISO2025

ISO17646:2025(en)

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ISO17646:2025(en)

Contents Page

Foreword

iv

1Scope

1

2Normativereferences

1

3Termsanddefinitions

1

4Principle

3

5Materialsandapparatus

3

6Preparationofsample

3

6.1Preparationoftestingsample

3

6.2Preparationofstandardsample

3

7Low-fieldnuclearmagneticresonancedetermination

3

7.1Generalparameters

3

7.2Calibrationparameterssetting

4

7.3Determinationparameterssetting

4

7.4Determinationofblanksubstrate

5

7.5Determinationoftestingsample

5

7.6Determinationofstandardsampleandestablishmentofstandardcurve

5

8Dataprocessingandmoisturecontentcalculation

5

8.1Dataprocessing

5

8.2Standardcurvefitting

5

8.3Expressionofresults

6

9Testreport

6

AnnexA(informative)Preparationofstandardsampleandstandardcurve

8

AnnexB(informative)Interlaboratorytestreport

10

Bibliography

20

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ISO17646:2025(en)

Foreword

ISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISOmemberbodies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOtechnicalcommittees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhastherighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnon-governmental,inliaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnicalCommission(IEC)onallmattersofelectrotechnicalstandardization.

TheproceduresusedtodevelopthisdocumentandthoseintendedforitsfurthermaintenancearedescribedintheISO/IECDirectives,Part1.Inparticular,thedifferentapprovalcriterianeededforthedifferenttypesofISOdocumentshouldbenoted.ThisdocumentwasdraftedinaccordancewiththeeditorialrulesoftheISO/IECDirectives,Part2(see

/directives

).

ISOdrawsattentiontothepossibilitythattheimplementationofthisdocumentmayinvolvetheuseof(a)patent(s).ISOtakesnopositionconcerningtheevidence,validityorapplicabilityofanyclaimedpatentrightsinrespectthereof.Asofthedateofpublicationofthisdocument,ISOhadnotreceivednoticeof(a)patent(s)whichmayberequiredtoimplementthisdocument.However,implementersarecautionedthatthismaynotrepresentthelatestinformation,whichmaybeobtainedfromthepatentdatabaseavailableat

/patents

.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.

Anytradenameusedinthisdocumentisinformationgivenfortheconvenienceofusersanddoesnotconstituteanendorsement.

Foranexplanationofthevoluntarynatureofstandards,themeaningofISOspecifictermsandexpressionsrelatedtoconformityassessment,aswellasinformationaboutISO'sadherencetotheWorldTradeOrganization(WTO)principlesintheTechnicalBarrierstoTrade(TBT),see

/iso/foreword.html

.

ThisdocumentwaspreparedbyTechnicalCommitteeISO/TC34,Foodproducts,SubcommitteeSC6,Meat,poultry,fish,eggsandtheirproducts.

Anyfeedbackorquestionsonthisdocumentshouldbedirectedtotheuser’snationalstandardsbody.Acompletelistingofthesebodiescanbefoundat

/members.html

.

©ISO2025–Allrightsreservediv

InternationalStandard ISO17646:2025(en)

Rapiddetectionofmoisturecontentinfreshmeat—Low-fieldnuclearmagneticresonance(LF-NMR)method

1Scope

Thisdocumentspecifiesrequirementsforrapiddeterminationofmoistureoffreshmeatbasedonlow-fieldnuclearmagneticresonance(LF-NMR)technology.

Thisdocumentisapplicabletotherapiddetectionofmoistureinfreshmeat.

2Normativereferences

Therearenonormativereferencesinthisdocument.

3Termsanddefinitions

Forthepurposesofthisdocument,thefollowingtermsanddefinitionsapply.

ISOandIECmaintainterminologydatabasesforuseinstandardizationatthefollowingaddresses:

—ISOOnlinebrowsingplatform:availableat

https://www.iso.org/obp

—IECElectropedia:availableat

https://www.electropedia.org/

3.1

freshmeat

meatthatretainsitsoriginalcompositionalandstructuralproperties,andhasnotbeensubjectedtoheating,canning,saltingordrying,etc.

[SOURCE:ISO23722:2021,3.22]

3.2

transverserelaxationtime

2

T

spin-spinrelaxationtime

timeconstantwhenthetransversemagnetizationvectordecreasesto37%ofthemaximumvaluethatcharacterizesthespeedofsignalattenuation

Note1toentry:Therelaxationprocessistheprocessofthespinninghydrogennucleusinthestaticmagneticfieldreturningfromtheexcitedstatetotheequilibriumstate.Thetimerequiredfortherelaxationprocessiscalledthe“relaxationtime”.

3.3

freeinductiondecayFID

nuclearmagneticresonance(NMR)signalreceived,resultingfromusingasingle90°radiofrequencypulsetoactivatethesample

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ISO17646:2025(en)

3.4

Carr-Purcell-Meiboom-GillCPMG

pulsesequencethatinvolvesapplyingmultiple180°radiofrequencypulsesafterapplyinga90°radiofrequencypulse

Note1toentry:Each180°radiofrequencypulseappliedwilldelaythesignalattenuationcausedbytheunevenmagneticfield,anddatathatarenotaffectedbymagneticfielduniformitycanbesampledattheechopeakofthesignal.

3.5

samplingbandwidthSW

frequencyrangeofthenuclearmagneticresonance(NMR)signalreceivedbythereceivercoilwhenthesignaliscollected

3.6

regulatefirstdataRFD

controlparameterforthestartingtimeofnuclearmagneticresonance(NMR)signalacquisition

3.7

pre-ampregulategainPRG

parameterusedtoshowthatthenuclearmagneticresonance(NMR)signalfromthereceivercoilispre-amplifiedtolevelsinalow-noisepre-amplifier

3.8

regulateanaloguegain1RG1

parameterusedtoshowthatthenuclearmagneticresonance(NMR)signalisfurtheramplifiedtolevelsinapre-amplifierfollowingthepre-amplification

3.9

regulatedigitalgain1DRG1

parameterusedtoshowthatthenuclearmagneticresonance(NMR)signalisamplifiedtolevelsafterconvertedtodigitalsignalsforaveragingandcomputerprocessing

3.10

inversioncurve

frequency-domainspectrumconvertedfromtheattenuationcurvecomposedofseveralpointsthroughtheinversionmethod

3.11

boundwater

2b

T

waterinmeatthatiscloselyboundtothepolargroupsofproteinbyhydrogenbonds

Note1toentry:Thetransverserelaxationtime(

3.2

)ofboundwaterisshorterthanthatofimmobilizedwater(

3.12)

andfreewater(

3.13

).

3.12

immobilizedwater

21

T

watertrappedwithinthemyofibrilsthatcannotmovefreely

Note1toentry:Thetransverserelaxationtime(

3.2

)ofimmobilizedwaterisbetweenthatofboundwater(

3.11)

andfreewater(

3.13)

.

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ISO17646:2025(en)

3.13

freewater

22

T

wateroutsidethemyofibrillarlatticeandalsooutsidethemusclecellthatcanmovefreely

Note1toentry:Thetransverserelaxationtime(

3.2

)offreewaterismorethanthatofimmobilizedwater(

3.12

)andboundwater(

3.11

).

4Principle

Themeatsystemcontainsatomicnuclei(1Hprotons)withfixedmagneticmoments,whichcanabsorbradiofrequencyenergyandgenerateNMRsignalsofthewaterhydrogenwhenstimulatedbyradiofrequencypulsesofspecificfrequenciesunderaconstantmagneticfield.Whenameatsampleisputinauniformstaticmagneticfield,aspecificnuclearmagneticpulsesequenceisusedtomotivatethe1Hprotonsofmoistureinthemeatsample.Afterthesampleabsorbstheexcitationenergy,anNMRsignalisproduced,whichisproportionaltothewatermassofthesample.Asthetransverserelaxationprocessoccurs,themoisturecontentofthemeatsampleisobtainedbyestimatingthefunctionalrelationshipbetweenthemoisturemassandthereceivedsignalamplitudeofcontrolsandsamples.

5Materialsandapparatus

5.1 Meatsamples,whichshouldbefreshmeat,withatemperatureof22°C±2°C.

5.2 Sharpknife,e.g.doublebladed(spacing1,0cm),ceramicknife.

5.3Nuclearmagnetictube(innerdiameter25mm).

5.4 Analyticalbalance,capableofweighingthesampleswithanaccuracyof0,0001g.

5.5 LF-NMRinstrument,auniversalLF-NMRanalysershallbeused.Thechambershouldaccommodatethetestsample.Thefieldstrengthshouldbeapproximately0,5Tto1,0T.Thespectrometerfrequencyshouldbeapproximately20MHzto23MHz.Theambienttemperatureinsidetheinstrumentshouldbeapproximately32°Cto35°C.

6Preparationofsample

6.1Preparationoftestingsample

Visibleskin,connectivetissueandfatshallberemoved.Themeatshallbecutinto1cmthickpiecesalongthenaturaldirectionofmusclefibrewithadouble-bladedknife.Themeatpiecesshallbefurthercutinto1cm×1cm×2cmmeatcuboidswithaceramicknife.Atleastthreemeatcuboidsshallbepreparedforeachsample.Visibleconnectivetissue,bloodvesselsandotherdefectsshallbeavoidedintheprocessofcuttingthemeatsamples.

6.2Preparationofstandardsample

See

AnnexA

.

7Low-fieldnuclearmagneticresonancedetermination

7.1Generalparameters

ThesequencesofFIDandCPMG,whichhavebeenwidelyrecognizedinthefieldofnuclearmagneticresonancetesting,shallbeselected.Theappropriateparametersforcalibrationanddeterminationshall

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ISO17646:2025(en)

beselectedfromameatmoisturenuclearmagnetictestsequencedatabase.Theparameterscanbesetaccordingtotheactualsituationofthesampletoensurecompletesignalattenuation.

7.2Calibrationparameterssetting

TheinstrumentshallbecalibratedusingthesequencesofFIDtoautomaticallyfindthecentrefrequencyandpulsewidth.

Calibrationparametersettingsasfollows:

—samplingbandwidth:SW=approximately100kHzto200kHz;

—spectrometerfrequency:SF=approximately20MHzto24MHz;

—regulatefirstdata:RFD=approximately0,002msto0,5ms(shouldbemodifiedinconjunctionwithSW,anditisrecommendedtohaveanRFDof0,08msatSW=100kHz);

—timewait:TW=approximately1000msto4000ms(longenoughtoensurecompleteecho);

—regulateanaloguegain1:RG1=10dbto20db;

—regulatedigitalgain1:DRG1=3;

—pre-ampregulategain:PRG=0,1,2,3(itisgenerallyrecommendedtobe0or1toavoidexcessivegain,whileifthesignalisweak,itcanbeincreasedappropriately);

—numbersampling:NS=2n;

—dataradius:DR=1.

7.3Determinationparameterssetting

ThesequencesofCPMGshallbeselectedfordeterminationparameterssettings.

Determinationparameterssettings:

—samplingbandwidth:SW=approximately100kHzto200kHz;

—spectrometerfrequency:SF=approximately20MHzto24MHz;

—regulatefirstdata:RFD=approximately0,002msto0,5ms(shouldbemodifiedinconjunctionwithSW,anditisrecommendedtohaveanRFDof0,08msatSW=100kHz);

—timewait:TW=approximately4000msto8000ms(longenoughtoensurecompleteecho);

—regulateanaloguegain1:RG1=approximately10dbto20db;

—timedata:TD=1024;

—regulatedigitalgain1:DRG1=3;

—pre-ampregulategain:PRG=0,1,2,3(itisgenerallyrecommendedtobe0or1toavoidexcessivegain,whileifthesignalisweak,itcanbeincreasedappropriately);

—numbersampling:NS=2n;

—dataradius:DR=1;

—echotime:TE=approximately0,2msto0,6ms(thereareslightdifferencesindifferenttypesofrawmeatanddifferentpartsofthemeat,anditisrecommendedtouse0,3msforpork,0,5msforbeefand0,2msto0,3msforchicken);

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ISO17646:2025(en)

—echonumber:NECH=approximately2000to5000(thevalueofNECH*TEishorizontalordinatevalueoftherelaxationspectrum,anditisrecommendedthatthedecayingareaoftherelaxationspectrumbeapproximately1/3to2/3ofthetotalrelaxationtime).

7.4Determinationofblanksubstrate

TheemptysampletubeshallbeputintothesamplemeasuringchamberoftheNMRinstrument,andthenthetestshallbeconductedaccordingtothedeterminationparameterssettingin

7.3

toobtainblanksubstratesignal.

7.5Determinationoftestingsample

Thetestingsamplesafterpreparation(see

6.1)

shallbeputintothemeasuringtubesandcalibratedto22°CpriortoputtingintothesamplemeasuringchamberoftheNMRinstrumenttocollectLF-NMRsignalsaccordingtothedeterminationparameterssettingin

7.3

(onerectangularspecimenisplacedpertube).ThenthepeakareasofT2b,T21,andT22areobtainedbydeductingtheblanksubstratesignal(see

7.4)

.

7.6Determinationofstandardsampleandestablishmentofstandardcurve

Thestandardfreeze-driedmeatsampleshallbeputintonuclearmagnetictube,andthenshallbeputintothesamplemeasuringchamberofthenuclearmagneticinstrumenttocollectbasicdata.Thenwatershallbeaddedby1%,5%,10%,30%,50%and70%(nolessthanfiverepeatsforeachgroup)onthebasisofthemeat'smass.After30min,themeatsampleswithdifferentwatercontentsshallbeputintothenuclearmagnetictubes,thenintothesamplemeasuringchamberfordatacollection(see

AnnexA)

andthenthestandardcurveshallbecreated.

8Dataprocessingandmoisturecontentcalculation

8.1Dataprocessing

2

ThenuclearmagneticsignalsofstandardandtestingsamplesshallbearrangedaccordingtoXassamplingtime(ms)andYassignalintensitytoobtaintheTrelaxationinversioncurvefromrelaxationattenuationcurve(CPMGcurve)ofcontinuoussampledistribution.ThemethodusedtocreatetheinversioncurveisSIRT(simultaneousiterative-reconstructiontechniques).Accordingtothetransverserelaxationtimeofthespectrumpeak,itcanbedividedinto:

—T2b=approximately1msto10msisboundwater;

—T21=approximately10msto100msisimmobilizedwater;—T22≥100msisfreewater.

2b 21 22

Accordingtothecorrespondinginversioncurveofwater,thecorrespondingnuclearmagneticsignalsarecalculatedrespectively,includingA(boundwaterpeakarea),A(immobilizedwaterpeakarea)andA(freewaterpeakarea).

8.2Standardcurvefitting

1 2

Standardsamplesshallbetestedaccordingtotheparametersetin

6.1,

andtheactualaddedwatermassshallbedenotedas(m,m,).Thesumofinversionpeakareasofthreekindsofwater(boundwater,immobilizedwaterandfreewater)inNstandardsamplesshallberecordedasS1,S2,,respectively.The

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ISO17646:2025(en)2

linearmodelbetweenmoisturemassandnuclearmagneticsignalintensity(sumofpeakareas)shallbeestablishedasshownby

Formula(1)

:

Y=K×X+B (1)

where

X isthemoisturemass(g);

K isthefittingslope;

B isthefittingintercept;

Y isthenuclearmagneticsignalintensity(sumofpeakareas)inthesampleinversioncurve.

8.3Expressionofresults

2

ThemassofthemeatsampletobemeasuredshallberecordedasM,andthetestshallbecarriedoutaccordingtothesameparametersandproceduresofthestandardsamplein

7.3

.TheTrelaxationsignalintensityofthesamples(thesumoftheareaoftheinversioncurve)shallbeobtainedandrecordedasS.Thenthecalculationofthemoisturecontent(C)inthemeatsampleshallbecalculatedasshownby

Formula(2)

:

KM

CSB100 (2)

where

K isthefittingslope;

B isthefittingintercept;

M isthemassofthemeatsampletobemeasured(g);

S isthesumoftheareaoftheT2relaxationinversioncurveofthemeatsampletobemeasured;

C isthemoisturecontentofthemeatsampletobemeasured(%).

Moisturemassofthemeatsample,X,ing,iscalculatedaccordingto

Formula(3)

:

K

XSB (3)

where

S

B′andK′

isthesumoftheareaoftheTrelaxationinversioncurveofthemeatsampletobemeasured;

arethereferencevaluesofparametercalibrationobtainedbyfittingtheresultsofstandardsamplestestedusingLF-NMRanddryingmethods.

Theresulttotwodecimalplacesshallbereported.

See

AnnexB

forresultsanalysis.

9Testreport

Thetestreportshallspecify:

—allinformationnecessaryfortheidentificationofthesample;

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ISO17646:2025(en)

—theInternationalStandardused(e.g.ISO1442:2023,ISO5725-1);

—thetestmethodused,withareferencetothisdocument,i.e.ISO17646:2025;

—theresult(s),includingareferencetotheclausewhichexplainshowtheresultswerecalculated;

—anydeviationsfromtheprocedure;

—anyunusualfeaturesobserved;

—thedateofthetest.

©ISO2025–Allrightsreserved

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ISO17646:2025(en)Moisturecontent

(%)

Standardmeatmass(g)

Wateraddition

X1(g)

Wateraddition

X2(g)

Wateraddition

X3(g)

Wateraddition

X4(g)

Wateraddition

X5(g)

Wateraddition

X6(g)

0

m1

0

1

m2

X1=m2/99

5

m3

X2=m3/19

10

m4

X3=m4/9

30

m5

X4=3m5/7

50

m6

X5=m6

70

m7

X6=7m7/3

AnnexA(informative)

Preparationofstandardsampleandstandardcurve

A.1Standardmeatsamplepreparation

A.1.1Freshmeatsamplesshallbetakenandvisibleskin,connectivetissueandfatshallberemoved.Themeatsamplesshallbecutinto1cmthickpiecesalongthenaturaldirectionofmusclefibrewithadouble-bladedknife,andthenmeatpiecesshallbecutinto1cm×1cm×2cmcuboidswithaceramicknife.Nofewerthan100cuboidsshallbepreparedforeachtest.Visibleconnectivetissue,bloodvesselsandotherdefectsshallbeavoidedintheprocessofcuttingthemeatsamples.Eachmeatcuboidshallbeweighed.

A.1.2Thepreparedmeatcuboidsshallbefrozenat−18°Cfor24h,andthenfreeze-drieduntilthesamplemassisconstant.

A.1.3Thefreeze-driedstandardsamplesshallbestoredinairtightdrycontaineratroomtemperatureandprotectedfromlightfornomorethanoneyear.

A.2Standardcurvepreparation

1 2

A.2.1Freeze-driedstandardsamples(nolessthanfivecuboids)shallbeweighed,andlabelledasm,m,m3,m4,m5,….Thenwatershallbeaddedaccordingto

TableA.1

toobtaindifferentmoisturecontents.

TableA.1

A.2.2Wateradditionmethod:Thefreeze-driedsamplesshallbeputintoanuclearmagnetictube,andthena1mlpipetteshallbeusedtotakeacertainamountofwateraslistedin

TableA.1.

Themeatsamplesshallbekeptatroomtemperatureformorethan30mintoabsorbwaterfully,andthenputintosamplemeasuringchamberoftheinstrumentfordatacollection.Watershallbeaddedtothesamesampleseveraltimesinturninordertoobtaindifferentmoisturecontents.Theamountofwateraddedshallbeinanascendingorder.

A.2.3ThesequencesofFIDandCPMGshallbeselected.Theappropriateparametersascalibrationparametersanddeterminationparametersshallbeselectedincludingsamplingbandwidth,spectrometerfrequency,regulatefirstdata,timewait,timedata,regulateanaloguegain1,regulatedigitalgain1,numbersampling,pre-ampregulategain,dataradius,echotimeandechonumber.

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ISO17646:2025(en)

2

2b 21

22 2b 21

22

A.2.4Thecontinuousdistributedrelaxationattenuationcurve(CPMGcurve)ofthesamplesshallbeobtainedbytakingthemeasuredresultswithsamplingtime(MS)asthehorizontalordinate(x-axis)andechointensityastheverticalcoordinates(y-axis).TheTrelaxationinversioncurveshallbeobtainedbyinversionfittingwithCPMGsamplingcurve.Accordingtothetimeintervalofthepeakoftheinversioncurve,T=approximately1msto10msisboundwater,T=approximately10msto100msisimmobilizedwater,andT≥100msisfreewater.A(thecorrespondinginversionpeakareaofboundwater),A(thecorrespondinginversionpeakareaofimmobilizedwater)andA(thecorrespondinginversionpeakareaoffreewater)shallbecalculated.ThepeakareasshallbesummedasS=A2b+A21+A22.

A.2.5Theregressionmodelshownin

Formula(A.1)

shallbeobtainedbytakingtheaddedmoisturemassXastheindependentvariableandthesumofpeakareasYasthedependentvariable:

Y=K×X+B (A.1)

where

X isthemoisturemass(g);

K isthefittingslope;

B isthefittingintercept;

Y isthesumofpeakareasinthesampleinversioncurve.

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ISO17646:2025(en)

Laboratoryi

Levelj

%

1

76,84

76,05

75,47

75,39

73,69

2

76,60

73,79

73,12

76,63

76,24

3

74,16

74,68

75,80

73,21

74,89

4

75,26

73,17

73,48

74,63

73,88

5

76,01

75,69

76,43

74,98

75,79

6

72,24

73,53

73,44

73,77

73,90

7

73,70

74,13

74,77

73,89

75,03

8

73,04

75,95

74,95

74,71

73,80

9

76,01

74,37

77,25

76,80

75,70

10

75,33

74,72

74,42

74,23

73,18

11

73,44

73,25

71,72

72,62

73,53

12

73,41

73,52

73,75

74,10

73,33

AnnexB(informative)

Interlaboratorytestreport

B.1General

Inthedesignandperformanceoftheprecisionexperiment,alltheprinciplesofISO5725-1wereobserved.Thebasicmethodusedthesamenumberoftestresultsineachlaboratory,witheachlaboratoryanalysingthesamenumberofthetestlevelsofthesample.Inthelayoutoftheexperiments,samplesfromonebatchofmaterialsweresentto12laboratories,whereeachobtainedexactly5replicatetestresultsunderrepeatabilityconditionsatonelevel.

B.2Statisticalanalysisofmoisturecontentinfreshpork

B.2.1Directdrymethod

B.2.1.1Originaltestresults

Intotal,12laboratoriesparticipatedinthedeterminationofmoisturecontentineachsample.Thetestresultsaregivenin

TableB.1

.

TableB.1—Originaltestresultsfordeterminationofmoisturecontentbydirectdryingmethod

B.2.1.2Cellmeans

Thecellmeansofthedeterminationofmoisturecontentaregivenin

TableB.2

.

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TableB.2—Cellmeansofthedeterminationofmoisturecontentbydirectdryingmethod

Laboratoryi

Levelj

%

1

75,49

2

75,28

3

74,55

4

74,08

5

75,78

6

73,38

7

74,30

8

74,49

9

76,03

10

74,38

11

72,91

12

73,62

B.2.1.3Cellstandarddeviation

Thecellstandarddeviationofthedeterminationofmoisturecontentaregivenin

TableB.3

.

TableB.3—Cellstandarddeviationofthedeterminationofmoisturecontentbydirectdryingmethod

Laboratoryi

Levelj

%

1

1,16

2

1,68

3

0,96

4

0,86

5

0,53

6

0,66

7

0,57

8

1,12

9

1,11

10

0,79

11

075

12

0,31

B.2.1.4Scrutinyofresultsforconsistencyandoutliers

B.GraphicalconsistencytechniquebyMandel’shandkstatistics

Calculatethebetween-laboratoryconsistencystatistich,aswellastheintra-laboratoryconsistencystatistick,foreachlevelofeachlaboratory.PlotthehandkvaluesforeachinorderoflaboratorytogettheMandel’shandkgraphs.See

FiguresB.1

and

B.2

.

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ISO17646:2025(en)

Horizontallinesrepresent1%and5%criticalvaluesofMandel’shandkstatistics,respectively.

FigureB.1—Mandel’sinterlaboratoryconsistencystatistic,h,groupedbylaboratoriesbydirectdryingmethod

Horizontallinesrepresent1%and5%criticalvaluesofMandel’shandkstatistics,respectively.

FigureB.2—Mandel’sintra-laboratoryconsistencystatistic,k,groupedbylaboratoriesbydirectdryingmethod

ItwasconfirmedthatnostragglerexistsbyMandel’shstatisticsandalsonooutlier.

Thekgraphshowsthatlaboratory2hadanoutlier.Becausefreshporksamplescannotbesentuniformly,porksamplesarepurchasedlocallybytheirrespectivelaboratoriesinaccordancewithunifiedstandards,hencetherecanbedifferencesduetovarioussaleschannelsforporksamplesindifferentregions.However,thislaboratoryisnotanoutlierlaboratory;furthermore,theaveragewatercontentofthefreshmeatmeasuredis75,28%,whichiswithinthenormalrangeforfreshporkwatercontent.Thereisnodirectevidencetosuggestthatthisresultisincorrect,sotheresultisretained.ItwasconfirmedthatnostatisticaloutlierexistsbyMandel’skstatistics.

B.Cochran’stest

ApplicationofCochran’stestledtothevaluesoftheteststatisticCgivenin

TableB.4

.

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TableB.4—StatisticalvalueofCochrantestfordirectdryingmethodC

Levelj

Freshmeat

Typeoftest

C

0,031

Cochran’steststatistics

stragglers(P=12)

0,288

Cochran’scriticalvalues

outliers(P=12)

0,343

Iftheteststatisticisgreaterthanits5%criticalvalueandlessthanorequaltoits1%criticalvalue,theitemtestedisregardedasastraggler.

Iftheteststatisticisgreaterthanits1%criticalvalue,theitemtestedisregardedasanoutlier.

ItwasconfirmedthatnostragglerexistsbyCochran’stestandalsonooutlier.

B.Grubbs’test

ApplicationofGrubbs’testtocellmeansledtothevaluesoftheteststatisticGshownin

TableB.5.

TableB.5—ApplicationofGrubbstestoncellmeanvalueofdirectdryingmethod

Levelj

Singlelow

Singlehigh

Doublelow

Doublehigh

Typeoftest

Freshmeat

1,662

1,551

0,621

0,554

Grubbs’teststatistics

stragglers(P=12)

2,412

2,412

0,2537

0,2537

Grubbs’critical