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食品專業(yè)英語FoodProfessionalEnglish01OVERVIEWOFFOODSAFETY02FOODRAWMATERIALINGREDIENTANDNUTRITION03ISSUESINFOODSAFETY04FOODADDITIVES目錄CONTENTS06FOODSAFETYTRACING07FOODSAFETYANDMICROBIALINFLUENCEFACTORS08FOODQUALITYMANAGEMENT09FOODQUALITYCONTROLANDSAFETYEVALUATION05FOODRISKANALYSISANDFOODQUALITY10CRISISMANAGEMENTFORFOODINDUSTRYLESSON6FOODSAFETYTRACING1.FoodtraceabilitysystemInrecentyears,thefrequentincidentsoffoodsafetyinacountryorregionwillnotonlythreatenthehealthofconsumersinothercountriesandeventheworld,butalsoweakentheirconfidenceforfoodsafetyandtheintegrityofcertainfood,evennationalandregionalmanagementsystemsduetotheintegrationofagriculturalproductionandfoodindustryaswellastheglobalizationoffoodtrade[1].Therefore,itisimperativetostrengthenthemanagementoffoodqualityandsafety,ensurefoodqualityandsafety,enhanceconsumers'trust,establishfoodtraceabilitysystemandrealizethetraceabilitysupervisionoffood[2].1.1FoodgeographicaloriginFoodtraceistheprocessofidentifyingaparticularproductorabatchofproductsfromthedownstreamofsupplychaintotheupstream[3].Foodgeographicalorigintracingmeansbuildingtheguidelines,techniques,meansanddocumentsrequiredbythatfoodcompaniesforestablishingfoodtrace,aswellasthesupervisiondepartmentfortracing,confirmingandrecalling.Foodauthenticityistheconsistencybetweenthefoodpurchasedbytheconsumerandthetrademarkorproductdescription,whichistheauthenticityoftheproduct.Foodgeographicaloriginauthenticityistoverifywherefoodactuallycomesfrominanobjectiveway.Itismoredifficulttodeterminewhichregionthefoodcomesfromthanwhetherthefoodisfromacertainregion.Thatistooeasyitisadifficultytorealizethefoodgeographicalorigintracing,northefoodgeographicaloriginauthenticity[4].Foodgeographicalorigintracingcanbeachievedbytracinginformationsuchaspaperpen,electroniclabelandeartag.Inthecaseofinformationbeinglostorforged,itcanbetracedthroughstableisotopefingerprint,mineralelementfingerprint,infraredspectrumfingerprint,organiccomponentfingerprintanalysisandsoon[5].LESSON7RESEARCHPROGRESSOFFOODTRACING1.2ThedevelopmentprocessoffoodqualitytracingFoodqualitytracingoriginatedinFrance,usedtoensurethequalityofwineandchampagnewhentherewerenolawsandregulationstoenforceit.Inearly21century,Europe's"madcowdisease"madefoodtracingincreasinglyimportant.Hencein2002,EuropeanUnionrule(No.178/2002)claimedthatallfoodssoldwithintheEuropeanUnionshouldbetrackedandtrackedsince2005.In2006,theEuropeanCommunityordinance(No.510/2006)requiredthatprotectionofthegeographicalandappellatenamesofagriculturalproductsandfoodshouldbeimplemented.In2008,AdministrativeMeasuresontheGeographicalIndicationofAgriculturalProductswascarriedout.In2009,FoodSafetyEnhancementActof2009requiredthatallnon-processedfoodsshouldbetaggedwithlabelstoidentifytheoriginintheUSA.InChina,foodsafetysupervisionsystemhasbeenbuiltaccordingtoFoodSafetyLawofPRCsince2009,andthenthislawwasrevisedandreferredtotheregulatoryrequirementsrelatedtotraceabilityrepeatedlyin2015.Inthesameyear,itwasrequiredtoimprovethequalityofagriculturalproductsandtheleveloffoodsafety,aswellasestablishaplatformfordatainformationsharingthroughtheInternetaccordingtotheCentralDocumentNo.1.LESSON7RESEARCHPROGRESSOFFOODTRACING1.3Fingerprinttechnologyoffoodqualitytracing
Foodqualityfingerprintingtechnologyreferstotheanalysisofthecommonnessandpersonalityofvariouscomponentsinfoodthroughpropertreatmentofthesamples,andthedifferentcharacteristicsofdifferentcomponentscanbeusedtoexpressdifferentcharacteristics(includingspectrum,chromatography,massspectrometryandotherspectra),andthenthechemicalcompositionandpropertiesoffoodarewellrepresentedbymeasuringthecharacteristicsoffood[6].Incombinationwithstoichiometry,theevaluationoffoodismoreobjectiveandcomprehensive,whichisalsointegrated,hierarchical,associative,etc.Itnotonlydependsontheadvancedanalysistechniques,butalsodependsonthemathematicalstatisticsmethodandcomputersimulationmethodology.Thefoodqualityfingerprintbasedonalotofelementworkisaneffectivereferencetoidentifyfoodsecurity.Fingerprintasanewqualitycontrolmodeiswidelyregarded,andtheapplicationofthistechnologywillplayanimportantroleinthequalitycontroloffoodandtheinspectionoffoodquality[7].LESSON7RESEARCHPROGRESSOFFOODTRACING2.Classificationoffoodqualitytracing.2.1Maintechniquesoffingerprinttracing.Itisveryimportantforthedomesticdevelopmenttodevelopthefastandaccuratetracingtechnologyofagriculturalproductsduetotheprotectionoforiginproductsaswellasthecounterfeitingandshoddyofexcellentagriculturalproducts.Agriculturalorigintraceabilityismainlyananalysischaracterizationtoidentifydifferentspecificindicatorsofregionalsourceofagriculturalproducts.Nowadays,thefingerprintmaptodistinguishtheoriginofagriculturalproductsisestablishedbasedonthetechniquesincludingthemineralelementsfingerprintsanalysistechnology,electronicnosefingerprinttechnology,nearinfraredspectralanalysistechnology,DNAfingerprinttechniques,metabonomicsfingerprinttechnologycombinedwithstoichiometrystudy,soasitcantracebacktotheoriginofdifferentkindsofagriculturalproductsformestablishingacharacteristicfingerprintthatcandistinguishtheoriginofagriculturalproducts.LESSON7RESEARCHPROGRESSOFFOODTRACING2.2TraceabilitytechnologyofmineralelementsOrganismsneedtointakemineralsfromthesurroundingenvironment,whichcannotbesynthesizedintheirbodiesandareeffectedbylocalwater,geologicalfactors,soilenvironment,etc.Thus,therearefingerprintcharacteristicsofmineralelementsintheorganismsofdifferentregions.Thistechnologycanselecttheefficientfeaturesbyanalyzingthecompositionandcontentofthedifferentsourceofmineralelementsinorganismwithmathematicalstatisticsmethodslikevarianceanalysis,clusteringanalysisanddiscriminantanalysis.Thenthediscriminantmodelanddatabaseareestablishedtorealizefoodtraceabilityandconfirmation.HaiyanZhaoetal.[8]showedthatthefingerprintanalysistechnologyofmineralelementscanbeusedinthediscriminationofwheatproducingarea.Wangetal.[9]proventhatmineralelements,asaqualityindexoftea,wererelatedtoitsqualityandsafety;atthesametimetheteamineralelementscarryingtheregionalcharacteristicfingerprintinformationcanbeusedasanimportantlandmarkusedinorigintracing.LESSON7RESEARCHPROGRESSOFFOODTRACING2.3ElectronicnosefingerprinttechnologyTheelectronicnoseisalsoknownasthescentscanner,whichcanquicklydeterminetheoverallinformationofvolatilecomponentsinsamplesthroughaspecificsensorarray,signalprocessingandpatternrecognitionsystem.Huetal.[10]usedtheelectronicnosesystemequipedequippedwith10sensorarraystoanalyzematurityof5batchesofcitruspickedatdifferenttimes(15d/batch)andthecorrectjudgmentratewas88%.Thisprovidesabasisforjudgingcitrusmaturity.Comparedwithtraditionalchemicalanalysismethodsandsensoryevaluationmethods,electronicnosefingerprinttechnologyhastheadvantagesofsimpleoperation,simplepretreatment,quickdeterminationandgoodreproducibility.However,therearestillmanyproblemsthatneedtobefurtherstudiedintermsofmanufacturingmaterials,testingenvironmentanddataprocessing.LESSON7RESEARCHPROGRESSOFFOODTRACING2.4Near-infraredspectrumtraceabilityanalysistechniqueNearinfraredandinfraredarekindsofrapidandnondestructivetestingtechniques,basedonthenon-stopvibrationandrotatingofmolecular.Eachonehasitsuniqueinfraredabsorptionspectrumdeterminedbyitscompositionandstructure,thusitcanbeusedtoanalyzeandauthenticatemolecularstructure.NingZhangetal.[11]establishedatraceabilitymodelforsheepinShandong,Hebei,InnerMongoliaandNingxia,usingnearinfraredspectruminSIMCApatternrecognitionmethodafterpretreatedwith5pointsmoothingandmultiplescattering,andtherecognitionrateofthemodelwere100%,83%,100%and92%respectively.PingZhangetal.[12]studiedtheadulterationofedibleoilusingnearinfraredspectroscopy,whichdistinguishedthreekindsofcookingoilandsesameoilmixedwithotherfatsclearly.QuanshengChenetal.[13]establishedmodelsofteavalidationofLongjing,Biluochun,QihongandTieguanyinusednear-infraredspectroscopycombiningwithSIMCApatternrecognitionmethod,andtherecognitionswere100%,83%,100%and92%,respectively.LESSON7RESEARCHPROGRESSOFFOODTRACING2.5DNAfingerprintingtechnologyDNAfingerprintisakindofgeneticmarkerbasedonthevariationofnucleotidesequenceamongorganismsthatcandirectlydetectthedifferencesbetweenindividualorganismsinDNAlevel,anditisadirectreflectionofgeneticvariationinDNAlevel.Fingerprintisapowerfultooltoidentifyvarietiesandstrains(includinghybridparentandinbredlines)withtheadvantagesofrapid,accurate,etc.Itsmainpurposeisvarietyimprovementandseedidentification,anditisverysuitableforidentificationoffoodadulterationandqualitytracingofvarietyresources.Someoftheexistingstudieshaveplayedanincreasinglyimportantroleinfish,alfalfa,rice,corn,wheat,meatproducts,fruitjuices,etc.LESSON7RESEARCHPROGRESSOFFOODTRACING2.6MetabolomicsfingerprinttechniqueMetabolomicsfingerprinttechniqueisakindofcomprehensivequalitativeandquantitativeanalysismethodconductedwithoutexplicittargetcompounds,whichcanbeusedtodetectthewholemetabolitesofacertainbio-sampleundercertainchromatographicconditions.Theaimistoquantitativelydescribethewholeendogenousmetabolites,andtheresponserulesofinternalandexternalchanges.Themainmethodisthequalitativeandquantitativeanalysis,themainmetabolitetargetanalysis,themetabolicprofileanalysis,metabolicfingerprintanalysisandmetabolomicsanalysistoallsmallmoleculemetabolitesofthewholecellsinabiologicalsystem,withinagiventimeandcondition.LESSON7RESEARCHPROGRESSOFFOODTRACING3.TheapplicationoffingerprinttechnologyinthetracingofagriculturalproductsThesourcetracingtechnologyofagriculturalproductsisoneoftheimportanttechnicalsupportsfortheprotectionofgeographicalindicationproducts,whichcanprovidethetheoreticalbasisforthetracingandconfirmationofgeographicalindicationproductsandregionalfamousproducts.Theeffectivemethodistoselectthecharacteristicfactorwhichcanrepresenttheregionalinformation,andanalyzeits‘fingerprint’characteristicsthroughstoichiometry,soastoidentifytheoriginoffood.BaoxinLu[14]determinedtheeffectiveindexoftheoriginofsoybeaninHeilongjiangusingthemineralelementfingerprinttechnique,andAs,Ru,GdandTb,asreliableindicatorswereselectedfrom46kindsofmineralelements.PinghuiLietal.[15]usedthefingerprinttechniqueofmineralelementstodeterminetheoriginofkidneybean,andselectedCa,As,MgandPt4elementstoestablishtheorigintracingmodelofkidneybean.YananZhaoetal.[16]carriedoutgeneticdiversityanalysisandscreeningto14pairsofSSRprimersfor35greenbeanvarietiesinHeilongjiangprovinceandconstructedgreenbeanSSRfingerprintandmolecularidentitycardusingSSRfluorescencelabelingtechnique,thisachievementcanbeusedfortheidentificationofgreenbeandvarieties.LESSON7RESEARCHPROGRESSOFFOODTRACING3.1ResearchonFingerprintTracingTechnologyofJaponicaRiceItisveryimportanttostudythefingerprintinformationtechnologyofriceoriginandestablishthericefingerprintdatabaseforthesoundnessanddevelopmentofthefoodsecuritycontrolsystemandthecorroborationsysteminHeilongjiangprovince.Duetotheuniquequalityandinfluenceofgeographicalindicationsbrandagriculturalproducts(GIproducts)underthedriveofeconomicinterests,thepricesoftheseproductsaremuchhigherthansimilarproductsinthemarket.TopromotethemanagementofGIproducts,itisimperativetostudythoroughlytheinfluencingfactorsoffingerprintInformationwhichisuniquetotheregionofGIproducts,establishingdiscriminantmodelsandconstructingdatabasestoenhancetheenforceabilityofrelevantlawsandregulations,andtopromotetheapplicationoftracingtechniquesinpractice.LESSON7RESEARCHPROGRESSOFFOODTRACING3.1.1FeasibilitystudyofthetracingtechnologyofmineralelementsinriceTheresearchontheoriginofdomesticfoodsourcesmainlyfocusesonthepreliminarystageofthefeasibilityofmineralelementfingerprintsonfoodorigintracing.Thecontentsofmineralelementsindifferentpartsofricecanbefoundtobesignificantlydifferent,whichresultedinthelossofK,Ca,NaandotherelementsaftermillingthroughusingX-rayphotoelectronspectrometertotesttherice.Atthesametime,thecontentandcompositionofmineralelementsinagriculturalproductscarrytheinformationoforigin.Thecontentandcompositionofmineralelementsindifferentagriculturalproductsaredifferent.Itisfeasibletoidentifytheoriginofricebymeansofmineralelementfingerprintanalysis.LESSON7RESEARCHPROGRESSOFFOODTRACING(1)Variationofmineralelementcontentinjaponicaricebyvariety,regionandprocessingprecisionThecontentofmineralelementsinriceisaffectedbymanyfactors.Theresultthatricevariety,regionandprocessingprecisioncaninfluencethecontentofmineralelementsinjaponicariceprovidestheoreticalreferencefortheapplicationoffingerprinttracingtechnologyofmineralelementsinagriculturalproducts.(2)AnalysisofsoilmineralelementsindifferentregionsThecontentofmineralelementsinfoodiscloselyrelatedtoitshabitat.Thatistosaythedistributionofmineralelementsinsoil,watersourceandotherresourcesaredifferent,resulttothemorestableandeffectivereflectionintoagriculturalproducts.Thecorrelationanalysisofelementsinthesoiloffoodandoriginwillmakethetracingmethodmorereliable.Theregionsofricecanbedistinguishedsignificantlythroughanalyzingtheelementwherericeiscloselyrelatedtomaternalsoil.LESSON7RESEARCHPROGRESSOFFOODTRACING(3)DiscriminantanalysisofmineralelementcontentscloselyrelatedtoregionindifferentregionaljaponicasamplesThemineralelementsneededforricearemainlyabsorbedfromthesoil.Thedistributionoftraceelementsinsoilaffectsthequalityofrice.Theinformationcarriedbycloselyrelatedelementscandistinguishtheoriginofrice.Thediscriminantmodelwasestablishedbyusingcloselyrelatedelements,andthecorrectclassificationratewashigher.LESSON7RESEARCHPROGRESSOFFOODTRACING3.1.2ConstructionofthenorthernjaponicafingerprintmapbasedonAFLPThenorthernDNAfingerprintdatabasecanbeconstructedbyestablishingamolecularmarkersystemofAmplifiedfragmentlengthpolymorphism(AFLP),whichisapplicabletothenorthernjaponicavarieties.ThetechnologycombinestheadvantagesofRFLPandRAPDtechnology,becomingbothreliableandconvenient.ItsprincipleisthatarandomrestrictedDNAfragmentwithdifferentmolecularweightisformedcutbyplantgenomicDNAenzyme,andthenthejointofthespecificcoenzymepointisconnectedtothetwoendsoftheenzymecuttingsection,afterthatPCRamplification,electrophoresis,radioactivityornon-radioactiveDNAfingerprintingwereperformedusingtheprimersofthespecificcomplementaryjoint.Wecanrevealtheaffinityofdifferentvarietiesofjaponicarice,andcandistinguishthejaponicaricevarietieswithdifferentrelativesusingAFLPmolecularmarkermethod.LESSON7RESEARCHPROGRESSOFFOODTRACING3.2ResearchonfingerprinttracingofmiscellaneousgrainsDNAfingerprintstracingtechnologyismainlyaimedatcontaininggenesofgeneticmaterial,analyzinggrainsbasesequencedifferencesingene,finallyachievingthepurposeofidentification,distinguishbetweengrainvarieties.3.2.1DiversityanalysisDiversitymainlyreferstothesumofgeneticvariationbetweendifferentgroupsofdifferentlivinggroupsorindividuals.Itprovidesanimportantbasisforthefullutilization,scientificbreedingandgeneticresearchofmiscellaneousgrainresourcestoanalyzethegeneticdiversityofgermplasmresourcesandunderstandthegeneticdistancebetweenpopulations.Inparticular,thevarietyofmilletvarietiesandtheestablishmentofadatabaseoforiginprovidethepossibilityfortracingandprotectionoforiginofexcellentmillet.LESSON7RESEARCHPROGRESSOFFOODTRACING3.2.2EstablishmentoffingerprintmapThegeneticmapisalineararrangementofgenesobtainedbygeneticrecombination,whichillustratestherelativerelationshipbetweenafewfunctionalgenesandgeneticmarkers.SSRmarkersaregenerallyusedasanchorsbecauseofitsco-dominant,locusstableandpolymorphichighcharacteristicsthatisbeneficialtointegratedifferentchaingroupsandmaplinkagegroupsorchromosomes.GeneticlinkagemapbasedonSSRmarkertechniqueishelpfultofurtherunderstandtheagronomiccharactersofgrainsatthemolecularlevel,whichhasgreatsignificancetostudygenelocalization,cloning,genomestructureandfunctionaswellasgeneticanalysisofimportanttraits.LESSON7RESEARCHPROGRESSOFFOODTRACING3.2.3GeneticmapconstructionThegeneticmapreferstothechromosomallinearlinkagemapwiththechromosomerecombinationexchangerateastherelativelengthunitandthegeneticmarkerasthemainbody.Theconstructionofgeneticmapisanimportantlinkingenomeresearch,alsothebasisofgenemappingandcloningeventhestructureandfunctionofthegenome.ThegeneticmapoflegumesDNAhasalwaysbeenahottopicintheworld.3.2.4SpeciesidentificationAlongwithmolecularbiology,especiallytransgenictechnologywidelyusedinthefieldofcropbreeding,therearealotofsimilaritiesandgeneticdifferencesinmorphologyofnewvarieties,whichresultstothatthetraditionalmorphologicalmethodscannotbeaccuratelyidentified.Atthesametime,thedomesticseedmarketpartofthephenomenonofpoorqualitydeepenedthedifficultyofvarietyidentification.Fromtheperspectiveofgenetics,varietypurityandauthenticityidentificationareessentiallytheidentificationofgenotypes.Therefore,theidentificationofplantvarietiesismoreaccurateandreliablebytheDNAlabelingtechnologyoftheDNAmoleculesdirectlyidentified.LESSON7RESEARCHPROGRESSOFFOODTRACING4.ResearchprospectofbiologicalfingerprinttracingtechnologyAtpresent,originofagriculturalproductsiscloselyrelatedtoitsquality,safetyandnutritionalquality.Origininformationistheimportantbasisforconsumerstochooseagriculturalproducts,anditisalsoaneffectivewaytoensurefoodsafetywherethefarmersandagriculturalenterprisespaymuchattention.TheconstructionofChina'sagriculturalproductqualitytraceabilitysystemstartedlate.Besides,duetosmallagriculturalproductionunitscale,largequantities,lowinformationizationdegreeandothernationalconditions,thetracingdevelopmentisstillveryslow.However,withtherapidimprovementofthelifequalityofconsumers,thedemandsforagriculturalproductsandattentiontothequalitativehavechanged.Inrecentyears,Chinahasenteredtherapiddevelopmentperiodofagriculturalproductqualityandsafetytracing.Variousbiologicalfingerprinttechniqueswithitshighsensitivity,fastanalysisspeed,andlowdetectionlimit,springsupinaspectsoftheeffectiveidentificationoforiginofagriculturalproducts,ensuringthequalityandsafetyofagriculturalproductsandmaintainingtheagriculturalenterprisegoodimage.Itnotonlyguaranteestheconsumer'srighttoknow,butalsopromotesthebenigndevelopmentofagriculture.LESSON7RESEARCHPROGRESSOFFOODTRACINGHowever,therearestillmanyproblemstobesolvedandimproved.Forexample:howtoscreenthesourcetracingindicatorseffectively;thenumberofsamplecollectionandthedeterminationofthe
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