乳化剂和稳定剂对软冰淇淋品质影响研究_英文_

1、StudyonEffectsofEmulsifierandStabilizeronQualityofSoftIceCreamLIU Mei-sen，HE Wei-ping(InstituteofFoodScienceofShenzhenOceanpowerIndustrialCo.Ltd.,Shenzhen518040,China)Abstract：Theeffectsofemulsifier(moleculardistilledmonoglyceride)andstabilizer(guargum)onthequalityofsofticecreamwerestudied.Therigidi

2、ty,meltingresistancepropertyandoverrunofsofticecreamwerealsostudiedassignificantindices.The resultsfromthevariationoftheseindicesshowedthatthereisadualisticeffectofemulsifier.Itwasfoundthat%ofemulsifier wastheoptimumdosage.Theinfluenceofstabilizeronmeltingresistancepropertyisapositivecorrelation,but

3、thereisalsoa dualisiticeffectofstabilizeronoverrun.Thestabilizergivestheoptimumeffectonoverrunwhentheoptimumdosageof stabilizeris0.8%,whilehigherorlowerthan%willresultinareductionoftheoverrun.Key words：soft ice cream；emulsifier；stabilizer；melting resistance property；overrun；rigidity乳化剂和稳定剂对软冰淇淋品质影响研

4、究刘梅森，何唯平(深圳市海川实业股份 食品研究所，广东深圳518040)摘 要：本文对乳化剂和稳定剂对软冰淇淋品质的影响进行了研究。重点考察了软冰淇淋的硬度、抗溶性以及膨化率三个指标，研究结果表明，乳化剂的影响变化具有双重性，% 用量是最佳比例；稳定剂对抗溶性的影响 具有正相关性，随着稳定剂用量增加，抗溶性提高；但是稳定剂对膨化率的影响呈现双重性，% 的用量为最 佳比例，用量小于%或者多于%均减低膨化率。 关键词：软冰淇淋；乳化剂；稳定剂；抗溶性；膨化率；硬度中图分类号：TS277文献标识码：A文章编号：1002-6630(2007)03-0158-06Softicecream,theleis

5、uredessertfood,hasseenitsbusinessincreasesharplywiththedevelopmentofsnacks. People,especiallychildrenandyoungfemalesarewildabout itnotonlyforleisurebutalsoforenjoyment.Therearemore than 100 different kinds of soft cream brand including Mcdonal'sandKFC'sintheChinesemarket.Theoutputwas200thous

6、andstons,andthesaleswere40hundred million RMBin2004.Furthermore,softicecreammachinesbusimess isalsoincreasingrapidlywiththeincreaseofsofticecream trade.SoitsmarketinChinaisquiteprosperous.Consumersconsumedsofticecreamlaterthanicecream. Therearedifferencesbetweensofticecreamandicecreamin recipeandpro

7、cessing.Theripeningtimeforicecreamisover10hlongerthanthatforsofticecream,theoverruninsoftice creamis30%50%,but80%120%inicecream1.Incon- trastwithicecream,thesofticecreamdoesnotneedharden-ingprocess,andcannotbestoredforsale.Thesearethedifferencesbetweensofticecreamandicecreamthatmake theirrecipetechn

8、ologiesdistinctive.Emulsifiersandstabiliz- erscanaltertherheologyandthermodynamicsstabilityof softicecreamserum,socanaffect thequalityofsoftice cream.Thisarticlepresentsastudyontheinfluencingmecha- nismofemulsifiersandstabilizersonthequalityofsoftice cream.1Materials and MethodsInstrumentandequipmen

9、tSoft ice cream machine(OPF3036)ShenzhenOceanpowerIndustrial;rotatingviscometer(NDJ-1).1.2MaterialsSugar,wholefatmilkpowder,hydrogenatedvegetable oilpowder,maltodextrin,casein,emulsifier,stabilizerfood收稿日期：2006-03-31基金项目：广东省地市引导项目(2004B26001143)作者简介：刘梅森(1968-)，男，高级工程师，博士，主要从事冰淇淋冷饮以及食品添加剂研究。工艺技术食品科学2

10、007, Vol. 28, No. 03159gradeboughtfrommarketing.1.3 BasicrecipeandpreparationofsofticecreamSugar500g,wholefatmilkpodwer220g,hydrogenated vegetable oil powder 100g, maltodextrin 150g, varying amountofemulsifierandstabilizerdrinkingwater3000g.Total solidis25%,fat4.8%,non-fatmilksolid%andtotal dextrose

11、14%.Weighedtheingredientsaccordingtothebasicrecipe intoacontainer,andadded3000mldrinkingwateratthe temperature70,Thenstirreduntilthemixwasdissolved, homogenizedwiththepressureof18MPa,andrestedfor15min.atroomtemperatureinordertolowerthetemperature ofthemixtoless30.Putthemixintothefrozencylinderof sof

12、ticecreammachinetofreezethemixandtopreparesoft icecream.After10min.orso,themachinestoppedautomati- callyandthesofticecreamwasready.1.4 DeterminationofviscosityTheviscosityofthemixwasdeterminedthriceatroom temperature,andthefinishedresultwasexpressedasthe averagevalue.1.5 Determinationofresistant-mel

13、tedpropertySofticecreamwasenclosedina50mlbeaker,thenthe beakerwasturnedonanironmesh,andthesofticecream wasallowedtoslipoutfromthebeaker.Itwasmadesure thatthesampleshadthesameweightandshape.Another beakerwasdisposedunderthemeshtorecovertheserum fromthemeltingsofticecream.Thepropertyofmeltingre- sista

14、ncewasmeasuredwiththemassofmeltedserumrecov- eredinthesecondbeaker.Theworsethemeltingresistance propertyoftheicecream,themorethemassofserumrecov- eredinthesecondbeakerin5min2.Calculatingequation:rateofmeltingresistance(%)=MM1 2Overrun(%) =×100M22Results and AnalysisTheeffectsoftheemulsifier'

15、;sconcentrationonthequalityofsofticecreamThedosageofguargum,astabilizer,wasfixedat0.8%, andtheconcentrationsofmoleculardistilledmonoglyceride, anemulsifier,weretakenas0.8%,1.0%,1.2%,1.4%,1.6% respectively.Theroom temperaturewas25.ViscosityThetemperatureoftheserumtotestwas26withNo.2rotator,at100r/min

16、.Theviscosityresultswere160170mPa·s.RigidityTheneedledescendinglengthin5minisshowninFig.1.20.6 11.2 1.6 Concentrationofemulsifier(%)Curveoftherigidityofsofticecreamvstheconcentration ofemulsifiertheweight(g)oftheserummelteddownfromsofticecream×100theweight(g)ofsofticecream30.6 11.2 1.6 1.6

17、 DeterminationoftherigidityAstainlesssteelneedlewithdiameter,length150mm, weight 30g, was inserted in the soft ice cream verticallyandallowedtoslipdown.Thedescendinglength in5min.wasmeasured.Thehardertherigidity,theshorter thedecendinglength2.1.7 Determinationoftheoverrun3M1 representstheweightof100

18、mlyetunfrozenserum and M2 represents the weight of 100ml frozen soft ice cream.Concentrationofemulsifier(%)Curve of the center temperature of soft ice cream vs the concentrationofemulsifierFig.1showedasignificanteffectontherigiditywiththechangeofemulsifier'sconcentrationsinthesofticecream. Rigid

19、ityincreasedalongwiththeincreaseofemulsifier's dosageintherangeoflowconcentration.Therigidity reacheditshighestvaluewhentheconcentrationofemul- sifierwas1.2%,asthedescendinglengthin5min.wastheCentertemperature()Descendinglength(cm)3.8 6 食品科学工艺技术1602007, Vol. 28, No. 03shortest(0.75cm).Therigidit

20、ywasdecreasingalongwiththeincreaseofemulsifier'sdosageintherangeofrelativelyhigh concentrationof1.2%1.6%.Therewasasimilarchanging trendbetweenthecentertemperatureofsofticecreamex- trudedandtherigidity.Thecentertemperatureofsoftice creamextrudedwasthelowest(4.9referencedFig.2) whentheconcentratio

21、nofemulsifierwas1.2%.Thereason wasthattherewasabestthreedimensionnetworkstructure intheserumofsofticecreamwhentheconcentrationofthe emulsifierwas1.2%,andtheelasticityandtenacityoffat globulewerealsoenhancedprimarilybecausethefatglobule wassurroundedbytheemulsifier,sothattherigidityreached itstop.Inc

22、ontrastwiththeconcentrationof1.2%,atthe relativelylowandrelativelyhighconcentrationofemulsifier, theemulsifiercouldn'tgivethebestthreedimensionalnet- workstructureintheserumofsofticecreambecausethe bestthreedimensionalnetworkneededtheoptimumdosage ofemulsifier.Therefore,theloosenessstructurecaus

23、eda decreaseintherigidity.Thewaythatthesofticecreamma- chineoperatesallowsittocontrolautomaticallythefrozen timeusingthemagnitudeofStirElectricalCurrentduring freezing.OncethemagnitudeofStirElectricalCurrentbe- comeshigherandreachesthesetvalue,themachinehalts automatically.Thetorquemomentofdriveshaf

24、tisincreas- ingalongwiththeprogressinrefrigerationofsofticecream serum,so,thebiggerthetorquemomentbecomes,thebig- gerthestirelectricalcurrentis.Theserumstructureviscosityvaluewasbiggerresulted fromthecompactnessofinnerstructurewhentheconcen- trationofemulsifierwasoptimum.Shearingmadethestruc- turevi

25、scosityvaluereduce.Thereforetheapparentviscos- ityvaluealsobecamesmallerwhentheserumwaschurned accordingtothefollowingequation.(apparentviscosity=Newtonviscosity+structureviscosity)4,thelowerappar- ent viscosity made by the drive shaft had lower torque moment, and the lower torque moment induced low

26、er stir electricalcurrent,thereforethefrozentimeofsofticecream waslonger,thecentertemperatureofsofticecreamextruded reacheditslowestvalue(4.9)resultedfromlongerfrozen time.The three dimensional network structure would not comeintobeingiftheconcentrationofemulsifierwasalittle bitlessthanitsoptimumint

27、heserum.thethreedimensional network structure in the serum would be broken if the concentrationofemulsifierwasbeyonditsbest.Becausethe emulsifierischaracteristicofdeemulsificationinemulsioniftheconcentrationofemulsifierisbeyonditsbest.Thebreakageofthreedimensionalnetworkstructure wasdueto therelease

28、oflipidenclosedinfatglobule.Meltingresistance10864the1st5minthe2nd5min the3rd5min2011.6 Concentrationofemulsifier(%)Curves of the concentration of emulsifier vs the meltingserum weight of soft ice cream(room temperature 25)Fig.3showedagoodandabadeffectonthemeltingresistanceofsofticecreamwhen thescop

29、eofemulsifier concentrationincreasedfrom%andfrom%respectivelyinthefirst5min.Thepropertyofmelting resistanceofsofticecreamreacheditsbestattheemulsifier concentrationof1.2%,whichwastheoptimumconcentration inthisstudy,andtheweightofmeltedserumwas.There weresimilarchangetrendsbetweentheweightofmelted se

30、rumandtheconcentrationofemulsifierinthesecond5 min.Butinthethird5min.Comparedwiththefirst5min,the resultswerethattheserumofsofticecreamwasinstable thermodynamically at relatively low concentration of emulsifier,andtheoptimumthreedimensionalnetworkstruc- turedidstillnotcomeintobeing,theairbubbleswere

31、dis- tributedasymmetrically,andthetenacityandstabilitywere notstrong,soitfollowedthatthepropertyofmelting resistancewasnotbetter.Thedeemulsificationbecamestrongerwhenthecon- centrationofemulsifierexceededitsoptimumof1.2%,andit wasbeyondthedemandforthermodynamicstabilityinthe serumofsofticecream.This

32、inducedthelipidtobereleased fromthefatglobules,andthenthelipidagglomerated.Hence, thethreedimensionalnetworkstructurewasbrokenandthe propertyofmeltingresistanceturnedbad4-5.OverrunFig.4showedasignificanteffectontheoverrunwiththechangeofemulsifier'sconcentrationinthesofticecream,theoverrunwasincr

33、easingalongwiththeincreaseofemulsifier concentrationintherangeof0.8%1.2%,andtheoverrun wasdecreasingalongwiththeincreaseofemulsifiercon-Weightofserum(g)1 7 4 6.9 1 7 工艺技术食品科学2007, Vol. 28, No. 0316140deemulsificationwastakenplacebeforetheinteractionofemulsifierandprotein,andmadetheproteinonthesurfac

34、e ofthefatglobulesfalloff,sothelipidreleasedfromthefat globuleswouldagglomerate.Thereasonthatthelipidwas releasedfromthefatglobuleswasduetothedeteriorationof themembrane.Itisadecisivefactortothequalityofsoftice creamthattheagglomerationoffatglobulesneedstobe controlledtoacertainextent.Duringfreezing

35、,theagglomerationoffatglobulesto certainextentallowstheimprovementofthewhippingandthe overrun,duetothestiffnessandthedrynessofsoftice cream.Hence theagglomerationinacertainextentcancon- trolthesizeofbubblesandimprovethestabilityofbubbles respectively.Thegrowthoficecrystalsisalsolimitedinside thebubb

36、lesbecauseofitssmallersize.Duringtheproduc- tionofsofticecream,theagglomerationoffatglobulesto certainextentwouldimprovetheappearanceoftheproduct, andtheproductofsofticecreamisofthecharacteristicsof finetissue,sweetnesstaste,andgoodmeltingresistance5 Concerningthesofticecream,itisimportantthatthe ag

37、glomerationoffatglobulesshouldbekepttocertainextent, butwhentheconcentrationofemulsifierismoreorless higherthanitsoptimum,thelipidwillbereleasedfromthefat globulesandagglomerate,andresultedin decreasingofthe overrunand greasinessfeelingoftheicecream5-6.The theoryisalsoprovedfromFig.4whichindicatstha

38、ttheover- rundecreasswhentheconcentrationofemulsifierishigher than1.2%.Thiscanbeexplainedbythefactthatthestron- gerdeemulsificationresultedfromtheincreaseofemulsifier causesahigheragglomerationoffatglobulesbyfavoringthereleasingofthelipidfromthefatglobules.383634323011.2 1.6 Concentrationofemulsifie

39、r(%)Curve of the overrun of soft ice cream vs. the concentrationofemulsifiercentrationintherangeof1.2%1.6%.Thebiggestoverrunof38%obtainedattheconcentrationof%of emulsifier.Emulsifieriscomposedofhydrophilicandhydropho- bicextremities.Ithastwokindsoffunctionsinsofticecream. Oneisemulsification，thatis,

40、theemulsifierallowsthe lipidstodistributestablyandformanemulsionintheserum ofsofticecream,whiletheotheristhattheemulsifierpro- motesthefatglobulestoagglomerateduringthefreezingof themix.Thegoodoverrun,thegoodmeltingresistanceprop- ertyandthegoodframeworkofsofticecreamresultedfrom thatthelipidscouldb

41、edistributedsymmetricallyintosmall fatglobules(diameter12m),sothethreedimensional networkstructureofsofticecreamwasformedasaresultof theagglomerationoflipid.Airasthethirdphaseenteredthemixandformeda largeinterfaceofairandliquidduringfreezing.Theinterface membranewascomposedmainlyofthematerialsinthel

42、iq- uidphase,andthemembranegainedtheelasticitybecause oftheattachmentofproteinsandobtainedthetenacitybe- causeoftheemulsifier.Themembranegainedabetterstabil- itybecausetherewasaframeworkformedbytheagglomera- tion of fat globules as being embedded in the outer of membrane.Intheserumofsofticecream,the

43、proteinsonthe surfaceofthefatglobulescouldpreventeffectivelythefat globulestoadhereoragglomeratetogether.Thephysicalpoweroriginatedfromthecrackingoffat globulesresultedfromchurninghasmadetheproteinmem- braneoneasiertothesurfaceofthefatglobulesfalloff duringfreezing.Thisphenomenonwasacceleratedbyemul

44、- sificationbecausetheemulsifierattachedeasiertothesurface ofthefatglobulesthanthecasein.Theemulsifiermadethe fatglobulesagglomeratebymeansofdestabilizationor deemulsificationduringfreezing.Thefunctionofemulsifier wastopreventfatglobulesfromagglomerating.Usually,theEffectsofstabilizerconcentrationin

45、thequalityofsofticecreamTheconcentrationofemulsifierwasfixedat1.2%，andtheconcentrationofstabilizerwassetat0.4%,0.6%,0.8%,1.0%,%respectively.ViscosityThetemperatureofthesampleswas26.Withtherotator，100r/min.Resultswereshownin.Therewasalinearityrelationshipbetweentheincreaseof viscosity andtheincreaseo

46、fstabilizerconcentration,butthelinearity relationshipalteredgraduallywhentheconcentrationofsta- bilizerexceeded1.0%.Itfollowedthattheserumwasofchar- acteristicNewtonliquidwhenthestabilizerconcentration covered from%to1.0%.RigidityOverrun(%)383533 3432食品科学工艺技术1622007, Vol. 28, No. 03600viscosityresul

47、tesinthattheserumtendesnottobemanipu-latedeasilyinthetankoffreezing.Thereforethethreedi- mensionalnetworkstructureinthesofticecreamisnotgood, andtheicecrystalsarenotenclosedentirelybyfatglobules, orthemembraneenclosingthesurfaceoficecrystalsisprone tobreak,whichmakesthesofticecreamweakinresistingthe

48、 effectthermodynamically,sothe meltingresistanceofsoft icecreamisthendecreased.Ononehand,thestabilizerhelpsimprovethemem- braneelasticityofbubblesinicecream,andtheelasticity andintensityofthenetworkstructureinicecreamaswell7. Ontheotherhand,thestabilizerdistributessymmetricallyon thesurfaceoficecrys

49、talsinsofticecreamtoprotectthe figureofsofticecream,soasnotonlytopreventthegrowth ofcrystalsbutalsotoimprovethemeltingresistance8.50040030020010000.2 0.4 11.2 Concentrationofemulsifier(%)Curveoftheviscosityofsofticecreamvs.the concentrationofstabilizer1Overrun500.4 11.2 40Concentrationofemulsifier(%

50、)Curveoftherigidityofsofticecreamvs.the concentrationofstabilizer3020Fig.6showedasignificanteffectontherigiditywiththechangeofstabilizer'sconcentrationinthesofticecream.The rigidityofsofticecreamisincreasingalongwiththein- creaseofstabilizerconcentration.Thehardertherigidity becomes,themoreslowl

51、ythepindescendes.100.2 0.4 11.2 Concentrationofemulsifier(%)Curve of the overrun of soft ice cream vs. the concentra- tionofstabilizerResistant-meltedFig.8indicatedthatthereisapositiverelationbetweenthe change of overrun and the change of the stabilizer concentrationintherangeof0.4%1.0%.Theincreaseo

52、f overrun resultes from the increasing of stabilizer concentration.Buttheoverrundecreaseswhentheconcen- trationexceedes1.0%.Thelowviscosityofserumbecauseofthelowconcen- trationofstabilizermakesthebubblesweakinkeepingair, whilethehighviscosityofserumbecauseofthehighercon- centrationofstabilizermakest

53、heairenteringserumnoteasy, sotheserumwillbedifficultinmixingwithairbychurningin thecourseoffreezing.Boththelowerandthehigherviscosity causenegativeeffectontheoverrunrespectively8.The abilityofembeddingairbychurningisvariablewiththe differentpropertiesoftheNewtonLiquid.98876the1st5minthe2nd5min the3r

54、d5min54311.6 Concentrationofemulsifier(%)Curves of the melting serum weight of soft ice cream vs. the concentration of stabilizer(room temp.25)Fig.7showedthatthepropertyofmeltingresistanceisimprovingalongwiththeincreaseofstabilizerconcentration, but the improving becomes slow when the concentration

55、exceedes0.8%.becausetheincreaseofviscosityresultsfrom theincreaseofstabilizer'sconcentration.Theincreasingof3ConclusionsEmulsifierandstabilizermakesignificanteffectsonofWeightofserum(g)Rigidity(cm)Viscosity(mPa·s)Overriun(%)8.4 1 4 3937 3630264963301608136工艺技术食品科学2007, Vol. 28, No. 03163麦芽糖

56、醇硬脂酸酯的合成研究张 灏，鞠兴荣，彭冬梅(南京财经大学食品科学与工程学院，江苏省粮油品质控制及深加工技术重点实验室，江苏 南京210003)摘要：以麦芽糖醇、硬脂酰氯为主要原料，在催化剂存在下，在醋酸溶剂中缩合成麦芽糖醇硬脂酸酯。通过考察催化剂种类及用量、溶剂的用量、反应温度、反应时间、原料配比等对反应的影响，确定了最佳反应条件。关键词：食品乳化剂；麦芽糖醇；硬脂酰氯；麦芽糖醇硬脂酸酯；合成ResearchonSynthesizingMaltitolStearicAcidEsterZHANG Hao，JU Xing-rong，PENG Dong-mei(KeyLaboratoryofGrai

57、nandOilsQualityControlandDeep-UtilizingTechnologyofJiangsuProvince,CollegeofFoodScienceandEngineering,NanjingUniversityofFinanceandEconomics, Nanjing210003,China)Abstract：Maltitolstearicacidesterwassynthesizedbycondensationofmaltitolwithstearoylchlorideinthepresenceofthecatalystandwithaceticacidassolvent.Effectsofcatalystandsolventamounts,reactiontemperatureandtime,andmolarratio ofst