《脂类理化性质》PPT课件

LIPIDPHYSICALANDCHEMICALCHARACTERISTIC,ZhangDequan,物理性质,气味和色泽芝麻油香气：乙酰吡嗪椰子油香气：壬基甲酮菜子油气味：黑芥子苷分解熔点和沸点油脂熔点最高40-55熔点温度低于37，消化率达到96%熔点高于37，不容易消化,烟点、闪点和着火点smokingpoint：发烟的温度flashpoint：被点燃但不能燃烧的温度firepoint：持续燃烧5s以上的温度精练油脂烟点在240左右折射率分子量大分子量小的饱和脂肪酸饱和脂肪酸不饱和脂肪酸油脂鉴别,结晶特性Polymorphism转变-2排列(DCL)-3排列(TCL)简单甘油酯容易形成稳定的结晶,DCL排列混合甘油酯容易形成结晶,TCL排列,结晶：大豆油、玉米油、花生油、椰子油、橄榄油、可可脂油、猪油结晶：棉子油、棕榈油、菜子油、乳脂、牛脂、改性猪油“调温”获得某种结晶产品可可脂生产Sn-StOSt、Sn-POSt,熔融特性融化SFI（SolidFatIndex）SFI测定方法：差示扫描量热仪（DSC）NMR脉冲NMR为AOCS的官方方法,油脂塑性塑性是指在一定的外力下，表观固体脂肪具有的抗变形的能力，油脂塑性取决于：SFI、脂肪晶型、熔化温度范围Shorteningoil油脂的液晶态（介晶相）层状：六方立方,乳化与乳化剂分散相（01-50微米的小滴）分散在连续相中乳浊液的制备：油脂、水、乳化剂、能量乳浊液不稳定的因素：分层、絮凝、聚结乳化剂选择方法：HLB值,一些常见乳化剂的HLB值,化学性质,水解氧化,1.Hydrolysisandsaponification,动物脂肪不利有利植物油鱼脂水解性质的应用构造脂质,2、氧化(酸败),自动氧化光敏氧化酶促氧化热氧化辐射氧化,FlavorQualityLossRancidflavorChangesofcolorandtextureConsumerAcceptanceEconomiclossNutritionalQualityLossEssentialFattyAcidsVitaminsHealthRisksGrowthRetardationHeartDiseases,2.1氧化机制,酶与非酶氧化两种机制自催化机制的与分子氧的反应是脂类氧化变质的主要反应光敏氧化触发了自动氧化,2.1.1自动氧化的一般特性,遵循自由基机制，具有5个特点干扰自由基反应的化学物质能显著抑制自动氧化光和产生自由基的物质能促进自动氧化产生大量的氢过氧化物由光引发的氧化反应量子产额超过1当原始物质为纯物质时存在一个相当长的诱导期,2.1.2MechanismsofLipidOxidation,ReactionsActivationEnergyProteinDenaturation100kcal/molNonenzymaticBrowningReaction50EnzymeCatalyzedReaction10-15LipidOxidation10-15,ActivationEnergyforChemicalReaction,HistoryofOxygen,Oxygen-ScheeleandPriestlyin1772.Tripletoxygen-Millikanin1928.Singletoxygen-Herzbergin1934.,TripletOxygenOxidation,C,H,C,H,C,H,2,C,H,C,H,C,H,2,(,C,H,2,),6,C,O,O,H,C,H,2,(,C,H,2,),3,C,H,3,100,75,50,BondEnergyofCarbonandHydrogen,kcal/mol,StearicacidOleicacidLinoleicacidLinolenicacid,C,H,3,(,C,H,2,),14,C,O,O,H,C,H,3,(,C,H,2,),6,C,H,C,H,(,C,H,2,),7,C,O,O,H,C,H,3,(,C,H,2,),4,C,H,C,H,C,H,2,C,H,C,H,(,C,H,2,),7,C,O,O,H,C,H,3,C,H,2,C,H,C,H,C,H,2,C,H,C,H,C,H,2,C,H,C,H,(,C,H,2,),7,C,O,O,H,C,H,2,C,H,2,C,H,2,InitiationofTripletOxygenOxidation,RH+引发剂,R,H,+,Initiationofautoxidationoccurswhenhydrogenatomat-methylenegroupindoublebondsofunsaturatedfattyacidsisremovedtoformanalkylradical(R).,Propagation,ROO,+,RH,ROOH,+,R,+,+,ROOH,+,OH,RO,RH,RO,ROH,R,R,+,3O2,ROO,Termination,2RO,ROOR,+,+,+,ROOR,RO,ROR,ROO,ROOR,R,+,R-R,R,ROO,+,R,R,ROO,O2,LinoleicAcidOxidationbyTripletOxygen,14,131211109,1211109,-H,+O,2,1211109,+H,C,H,2,C,H,C,H,C,H,2,C,H,C,H,C,H,2,R,(,C,H,2,),3,C,H,3,INITIATION,(METAL),(,C,H,2,),4,C,H,3,C,H,C,H,C,H,C,H,C,H,2,R,C,H,(,C,H,2,),4,C,H,3,C,H,C,H,C,H,C,H,C,H,2,R,C,H,O,O,PROPAGATION,R=(CH2)6-COOH,1211109,HYDROPEROXIDE,DECOMPOSION,-OH,+H,1211109,TERMINATION,(PENTANE),C,H,C,H,C,H,C,H,C,H,C,H,2,R,(,C,H,2,),4,C,H,3,O,O,H,(,C,H,2,),4,C,H,3,C,H,C,H,C,H,C,H,C,H,2,R,C,H,O,C,H,3,(,C,H,2,),3,C,H,2,C,H,3,(,C,H,2,),3,C,H,3,O,C,H,C,H,C,H,C,H,C,H,C,H,2,R,+,R=(CH2)6-COOH,SingletandTripletOxygen,MolecularOrbitalofTripletOxygen,RH+O2自由基35kcal/mol,MolecularOrbitalofSingletOxygen,SingletOxygenFormation,3O2+Sensitizer,H2O2+OCI-,H2O2+O2-,Ozone,Endoperoxides,OH-+O2-,Enzymes,O2-+Y+,1O2,O2-,O2-+O2-,H2O2+HO2-,RCOO+RCOO,C,H,3,C,H,2,C,H,C,H,C,H,2,C,H,C,H,C,H,2,C,H,C,O,O,H,(,C,H,2,),6,C,H,2,C,H,O,C,H,3,C,H,2,C,H,C,H,C,H,2,C,H,C,H,C,H,2,C,H,O,C,H,3,C,H,2,C,H,C,H,C,H,2,C,H,O,O,C,H,C,H,2,C,H,1O2,1O2,O,氢过氧化物形成：ReversionFlavorfromLinolenicAcidbySingletOxygenOxidation,O,2-(2-pentenyl)-furan,-H2O,C,H,3,C,H,2,C,H,C,H,C,H,2,C,H,O,O,C,H,C,H,2,C,H,C,H,3,C,H,2,C,H,C,H,C,H,2,C,C,H,2,O,C,H,2,C,H,O,C,H,3,C,H,2,C,H,C,H,C,H,2,C,C,H,C,H,C,H,O,H,O,H,C,H,3,C,H,2,C,H,C,H,C,H,2,O,C,H,3,C,H,2,C,H,C,H,C,H,2,C,H,O,O,C,H,C,H,2,C,H,O,H,-OH,氢过氧化物裂解：ReversionFlavorCompoundsfromSoybeanOil,2-(2-pentenyl)-furan,C,H,3,C,H,2,C,H,C,H,C,H,2,O,C,H,3,C,H,2,C,H,C,H,C,H,O,2,2-(1-pentenyl)-furan,Reactionof3O2and1O2withLinoleicAcid,R,R,R,R,O,O,H,3O2,Conjugated,Conjugated,R,R,R,R,R,R,HOO,3O2,-H,R,R,R,R,O,O,H,O,O,H,R,R,1O2,R,R,H,O,O,R,R,H,O,O,Conjugated,Nonconjugated,ReactionRatesofLipidOxidation,R+3O2K=109M-1sec-1ROO+OleicAcidK=1M-1sec-1ROO+LinoleicAcidK=60M-1sec-1ROO+LinolenicAcidK=120M-1sec-1ROO+ROOK=105-107M-1sec-1R+AntioxidantsK=107M-1sec-1RH+1O2K=105M-1sec-1,RelativeReactionRatesof3O2and1O2withOleic,Linoleic,andLinolenicAcids,Tripletoxygen310441047104,Singletoxygen12777,OleicLinoleicLinolenicAcidAcidAcid,Formationof1O2bySensitizers,GroundState,ExcitedState,hv,FluorescenceK=2108/sec,1Sen,1Sen*,K=1-20108/secISC,Phosphorescence,K=10-104/sec,SingletOxygen,1O2,K=1-3109/sec,3Sen*,3O2,光敏氧化,Lipid,FreeRadical,型,型,PhotosensitizersinFoods,ChlorophyllProtoporphyrineRiboflavinRedNo.3,EnzymaticOxidation（lipoxygenase,Lox）,Hydropeorxideatthe-6positionofunsaturatedfattyacid,Polyunsaturatedfattyacids(acis,cis-1,4-pentadieneunit),Lipoxygenase,热氧化,热分解热聚合热缩合,辐射氧化,过氧化脂质几乎可以与食品中的任何成分反应，降低品质氢过氧化物几乎与人体内所有分子或细胞反应，破坏和细胞结构脂质在常温或高温下氧化均产生有害物质,油脂氧化的安全性,影响自动氧化的因素,脂肪酸性质氧与氧分压温度表面积水分过渡金属元素光和射线抗氧化剂乳化,ControlofLipidOxidation,ApplicationofantioxidantsEliminationofoxygenbynitrogenflushingorvacuumpackagingEliminationofphotosensitizersDenaturationoflipoxygenaseLowtemperatureanddarkstorage,CharacteristicsofFreeRadicalsinOxidation,H:HydrogenatomThesimplestfreeradicalO2-:SuperoxideanionAnoxygen-centeredradical.LimitedreactivityHO:HydroxylAhighlyreactiveoxygen-centeredradical.IndeedattacksallmoleculesinhumanbodyRO2:PeroxylOxygencenteredradicalsformedduringtheRO:Alkoxybreakdownoforganicperoxides,FunctionofAntioxidantonLipidOxidation,InhibitsorslowstheformationoffreealkylradicalsintheinitiationstepInterruptsthepropagationoffreeradicalchainDelaysthestartorslowsthechemicalreactionrateoflipidoxidation.,TypesofAntioxidants,HydrogendonatingcompoundsSingletoxygenquenchersMetalchelatorsEnzymesOxygenscavengersandReducingagents,HydrogenDonatingAntioxidants,StandardOne-ElectronReductionPotential,CompoundsE(mV),HO,H+/H2O2310RO,H+/ROH1600ROO,H+/ROOH1000PUFA,H+/PUFA600Catechol,H+/Catechol530-Tocopheroxyl,H+/-Tocopherol500Ascorbate-,H+/Ascorbate282,CharacteristicsofHydrogenDonatingAntioxidants,Themajorhydrogendonatingantioxidantsaremonohydroxyorpolyhydroxyphenoliccompoundswithvariousringsubstitutions.Theantioxidantfreeradicaldoesnotinitiateanotherfreeradicalduetothestabilizationofdelocalizationofradical.,ReactionofAntioxidantswithRadicals,R+AHRH+A,RO+AHROH+A,ROO+AHROOH+A,ReactionofAntioxidantswithRadicals,EffectivenessofAntioxidants,Thedifferenceofone-electronreductionpotentialbetweenlipidradicalandantioxidantradical.Thestabilityofantioxidantradicals-Theresonancedelocalization-Furtheroxidationofantioxidantradicals,ResonanceofAntioxidantRadicals,O,H,C,(,C,H,3,),3,O,C,H,3,C,(,C,H,3,),3,O,C,H,3,O,.,O,C,H,3,C,(,C,H,3,),3,O,.,C,(,C,H,3,),3,O,C,H,3,O,.,O,C,H,3,C,(,C,H,3,),3,O,.,R,RO,ROO,RH,ROH,ROOH,StabilityofAntioxidantRadical,O,C,C,H,3,C,H,3,C,H,3,O,C,H,3,TargetsofAntioxidant,Antioxidantscanreactwithperoxylradicalsratherthanalkoxylradicals.Themostprevalentradicalisperoxyl(ROO)radical.Peroxylradicalhastheloweststandardoneelectronreductionpotentialamongalkyl,alkoxylandperoxylradicals,SyntheticAntioxidants,Butylatedhydroxyanisole(BHA),Butylatedhydroxytoluene(BHT),Propylgallate,Tertiarybutylhydroquionone(TBHQ),NaturalAntioxidants,BenefitsHealthimplicationStabilityinfoodsystemLimitsCharacteristicflavorSafetytestrequired,Tocotrienols,O,H,O,R,1,R,2,R,3,C,H,3,C,H,3,C,H,3,C,H,3,TrivialNameChemicalNameR1R2R3-Tocotrienol5,7,8-TrimethyltocotrienolCH3CH3CH3-Tocotrienol5,8-DimethyltocotrienolCH3HCH3-Tocotrienol7,8-DimethyltocotrienolHCH3CH3-Tocotrienol8-MethyltocotrienolHHCH3,AntioxidantMechanismofTocopherol,TransferofphenolichydrogenScavengingofsingletoxygenRegenerationoftocopherolinthepresenceofascorbate,Tocopherol,Achainbreakingantioxidantcompeteswithpolyunsaturatedlipidforthelipidperoxylradicals.,-Tocopherol-Tocopherylsemiquinone,Lipidradicals,Lipidradicals,-Tocopherylquinone,Resonanceof-TocopherolRadicals,O,O,C,H,3,H,3,C,C,H,3,C,16,H,33,C,H,3,R,RO,orROO,-Tocopherol,O,H,O,C,H,3,H,3,C,C,H,3,C,H,3,C,H,3,C,H,3,C,H,3,O,C,H,3,C,H,3,H,3,C,C,H,3,C,16,H,33,O,O,C,H,3,H,3,C,O,C,16,H,33,C,H,3,C,H,3,O,C,H,3,H,3,C,O,C,16,H,33,C,H,3,C,H,3,RH,ROH,ROOH,R,RO,orROO,EffectsofDietTocopherolontheContentofTocopherolinEggYolk,EffectsofTocopherolontheStabilityofEggYork,0,5,10,15,20,25,30,35,40,45,0,2,4,6,8,Time(Days),TotalHeadspaceVolatiles(1000),25gTocopherol/gyolk,45gTocopherol/gyolk,50gTocopherol/gyolk,75gTocopherol/gyolk,Control,AscorbicAcid,HydrogendonationtolipidradicalsQuenchingofsingletoxygenRemovalofmolecularoxygenRegeneratetocopherolradicalsProoxidantReduceferricirontoferrousiron,AscorbicAcid,O,O,O,H,O,H,C,H,C,H,2,O,H,O,H,O,O,O,O,H,C,H,C,H,2,O,H,O,H,L-Ascorbicacid,Dehydroascorbicacid,-H,-H,R,RO,ROO,R,RO,ROO,AscorbicAcidandRelatedCompounds,L-AscorbicAcid,O,O,H,O,H,C,H,O,C,H,2,O,H,H,O,H,ErythorbicAcid,AscorbicPalmitate,O,O,H,O,H,O,H,C,H,C,H,2,O,H,O,H,O,O,O,H,O,H,O,H,C,H,C,H,2,O,C,(,C,H,2,),14,C,H,3,O,H,SynergisticEffectofTocopherol&AscorbicAcid,SingletOxygenQuencher,SingletOxygenQuenchingMechanism,ISC,3O2,A,1Sen,1Sen*,3Sen*,1O2,AO2,Kq,Kox-Q,QO2,Kd,Q,Q,1Sen,1Sen,3O2,3O2,hv,Carotenoids,C,H,O,b-,Carotene,Apo-8-carotenal,O,Canthaxanthin,O,b-,PeroxideValue(meq/kgoil),StorageTime(hr),Effectsof-Apo-8-Carotenal,-CaroteneorCanthaxanthinontheSoybeanOilOxidativeQuality,QuenchingMechanismofb-CaroteneonSingletOxygenOxidation,1/SoybeanOil(1/M),1/Peroxide(1/M),SingletOxygenQuenchingRatesofCarotenoids,CarotenoidsNumberofConjugatedQuenchingRateDoubleBondsConstants(M-1sec-1)-Apo-8-carotenal102.86109-Carotene114.60109Canthaxanthin131.121010,SingletOxygenQuenchingRateofCarotenoids,CarotenoidsNumberofConjugatedRateConstantsDoubleBonds(109M-1sec-1)Astaxanthin139.88Isozeaxanthin117.31Zeaxanthin117.03Lycopene116.89Lutein105.86,SingletOxygenQuenchingRatesofTocopherols,Singletoxygenquenchingability:-Tocopherol,-Tocopherol:2.70107(M-1sec-1),SingletOxygenQuenchers,SingletOxygenQuencherQuenchingRate(M-1sec-1)-Carotene4.60109Ascorbicacid1.08108-Tocopherol2.70107,MetalChelators,ProoxidantMechanismsofMetals,HydroperoxidedecompositiontoformperoxylradicalandalkoxylradicalFe3+ROOHFe2+ROO+H+Fe2+ROOHFe3+RO+OH-FormationsofalkylfreeradicalbydirectreactionFe3+RHFe2+R+H+ActivationofoxygenforsingletoxygenformationFe2+3O2Fe3+O-21O2FormationofhydroxylradicalFe2+H2O2Fe3+OH-+OH,k1,k2,k2k1=105,ReactionbetweenMetalandHydroperoxide,RapidExponentialincreaseinoxidationduringpropagationstepb-ScissionofalkoxylradicaltolowmolecularweightcompoundsCopperis50fasterthanferrousionindecomposinghydrogenperoxideFerrousis100fasterthanferricironindecomposinghydrogenperoxideFerrousis1015timesmoresolublethanferriciron,MetalChelators,PhosphoricacidCitricacidAscorbicacidEthyleneDiamineTetraAcetate.(EDTA)ProteinssuchasTransferrin,OvotransferrinAminoacidsandPeptides,MechanismofMetalChelators,FormationofcomplexionsorcoordinationcompoundswithmetalsPreventionofmetalredoxcyclingOccupationofallmetalcoordinationsitesFormationofinsolublemetalcomplexesSterichindranceofinteractionsbetweenmetalsandlipidintermediates,Phospholipids,Phosphatidylethanolamine,C,H,2,O,C,O,R,1,C,H,O,C,O,R,2,C,H,2,O,P,O,O,O,C,H,2,C,H,2,N,H,2,-,Phosphaticacid,-,C,H,2,O,C,O,R,1,C,H,O,C,O,R,2,C,H,2,O,P,O,O,O,-,M,O,C,O,C,H,2,O,C,O,C,H,2,N,C,H,2,C,H,2,O,O,N,C,O,C,H,2,C,O,C,H,2,EthyleneDiamineTetraAcetate(EDTA),InteractionofChealatorandMetal,EnzymaticAntioxidants,2Glucose+2O2+2H2O2Gluconicacid+2H2O2,GlucoseOxidase/Catalase,2Glucose+O22Gluconicacid,2H2O22H2O+O2,GlucoseOxidaseCatalase,Catalase,GlucoseOxidase,OxygenScavenging,SuperoxideDismutase,2O,2,O,2,-,+,2H,+,+,SuperoxideanionparticipatesinoxidativereactionsMaintainingtransitionmetalsintheirreduced,activestatePromotingthereleaseofmetalsboundtoproteinsProducingsingletoxygen,SuperoxideDismutase,+,Catalase,2H,2,O,2,O,2,2H,2,O,3,GlutathionePeroxidase,H2O2+2GSH2H2O+GSSGLOOH+2GSHLOH+H2O+GSSG,GSH:ReducedglutathioneGSSH:Oxidizedglutathione,OxygenScavengers,OxygenScavengersandReducingAgents,AscorbicacidAscorbicpalmitateErythorbicacidSodiumerythorbateSulfites,OxygenScavengerMechanisms,C,H,3,S,H,C,H,3,S,S,C,H,3,O,2,+,O,O,O,O,H,C,H,C,H,2,O,H,O,H,HO,2,+,O,2,+,HO,+,H,O,S,O,H,O,H,O,S,O,H,O,O,O,2,2,SuperoxideDismutase,2O,2,O,2,-,+,2H,+,+,H,2,O,2,SuperoxideDismutase,+,Catalase,O,2,2H,2,O,3,2H,2,O,2,Producingtripletoxygenfromsuperoxideanion,3,MultifunctionalAntioxidants,TocopherolAscorbicacid,AntioxidantInteractions,CombinationofmetalchelatorandfreeradicalscavengingantioxidantsCombinationofdifferentantioxidantslike-tocopherolandascorbicacid,AntioxidantSources,Flavonoids,O,H,O,H,O,H,O,O,O,H,H,O,QuercetinFlavonols,O,O,H,O,O,H,H,O,G,l,u,c,os,i,de,O,H,Cyanidin-3-glucosideAnthocyanins,Flavonoids,SecondaryproductsofplantmetabolismMetalchelatingabilitySuperoxideanionscavengersAnthocyanines,catechins,flavones,flavonols,isoflavone,andproanthocyanidins,Vegetables,Cacaobeans,Potato,Tomato,Spinach,Legumes,Garlic,andSeaweedPolyphenoliccompounds,Fruits,Wines:AnthocyaninPolyphenoliccompounds,Tea,H,O,O,H,O,O,H,O,H,O,H,Epicatechin,H,O,O,H,O,O,H,O,H,O,H,O,H,Epigallocatechin,SesameSeed,Sesamol,O,O,O,H,Sesamolinol,O,O,O,O,O,O,C,H,3,O,H,HerbandSpice,Sage,Ginger,Greenpepper,LavenderandRosemary,CarnosoicAcid,C,O,H,3,C,C,H,3,H,O,O,H,C,H,3,C,H,3,O,Carnosol,O,H,O,H,H,O,O,H,O,O,H,O,O,C,RosemarinicAcid,ReactionRatesofCarnosolandCarnosicAcid,O,H,H,O,H,H,O,O,C,O,H,O,H,H,O,O,C,+,LOO,LOOH,+,Carnosicacid,3107M-1s-1,O,H,H,O,C,H,O,O,O,H,O,C,H,O,O,+,+,Carnosol,2106M-1s-1,LOO,LOOH,Soybean,Chlorogenicacid,caffeicacid,ferulicacid-MetalchelationandsingletoxygenquenchingIsoflavones-phytoestrogeneffects-Metalchelationandhydrogendonation,O,O,O,H,O,H,C,O,O,H,O,H,H,O,H,O,Chlorogenicacid,GenisteinOHOHDaidzeinHOH,IsoflavonesR1R2,1,2,Soybean,R,Ginseng,Ferulicacid,Caffeicacid,Ginseng,H,O,O,C,H,3,C,O,O,H,Vanillicacid,O,H,O,O,H,O,H,O,O,H,Kaempferol,H,O,O,C,H,3,C,H,C,H,C,O,O,H,H,O,O,H,C,H,C,H,C,O,O,H,Ginseng,Singletoxygenquenchers:CaffeicacidKaempferolVanillicacidSalicylicacidFerulicacidLinoleicacidinaqueoussystemunderdark:KaempferolMaltolVanillicacidSaponinSalicylicacidFerulicacidMetalchelationactivity:KaempferolMaltolVanillicacidFerulicacidCaffeicacid,AminoAcid,PeptideandProtein,Glycine,methionine,andlysineinemulsionsystem-antioxidantactivityatlowconcentrationandhighpH.Carnosineinhibitstheactivitiesofhemoglobin,lipoxygenase,iron,peroxyl,andhydroxylradical.Ferritinandtranferritinproteinsbindiron,MaillardReaction,ReducingSugarsand-aminoacids,N-glycosylamineorN-fructosylamine,1-Amino-1-deoxy-2-ketose(Amadoriintermediate)or2-Amino-2-deoxy-1-aldose(Heynesintermediate),Reductonesanddehydroreductones,FuransThiophenesPyrroles,Retroaldolcondensation,H2SNH3,Streckerdegradation,AminoAcids,HydroxyacetoneHydroxyacetylaldehydeAcetoinAcetylaldehyde,GlyoxalPyruvaldehydeGlycerolaldehyde,Aldehydes+-aminoketone(Methional,NH3,H2S),Heterocyclizaion,PyrazinesPyridinesOxazoles,ThiazolesPyrroles,C,H,3,C,O,C,O,H,C,O,H,C,H,O,H,C,H,O,H,C,H,2,O,H,Reductone,AntioxidantsfromMaillardBrowning,Nitrogeneouscompounds,Ethylthiol,C,H,3,S,H,C,H,2,PolarityofAntioxidants,Polarantioxidantsaremorea