2023學(xué)年完整公開(kāi)課版DairyProcessIIICAU

DairyProcessingDr.StephanieClarkmilkmade@AssociateProfessorofFoodScienceIII.MilkPowdersStepsinvolvedincreatingdrydairyproductsFiltrationConcentrationEvaporationDryingTerminologyFeedLiquidenteringamembraneseparationprocessPermeateSolutionthatflowsthroughthemembrane(filtrate)RetentateSolutionthatisretained;unabletopassthroughthemembrane(concentrate)FluxFlowofpermeatethroughthemembraneperunitareaandunittimeFiltrationOptionsReverseosmosis(RO)Nanofiltration(NF)Ultrafiltration(UF)Diafiltration(DF)Microfiltration(MF)TraditionalfiltrationReverseOsmosisMembranesize:10-4to10-3mmRemoveswater(retentatedesired)Tightestmembrane(waterandaqueoussaltsandionsallowedthrough)Pressure:1to10MPa(145to1450psi;10to100bar)Applications:desalination,dealcoholization,concentration,dehydrationofwheyNanofiltrationMembranesize:10-3to10-2mmRemoveswaterandmonovalentions(Na+,Cl-)“LooseRO”membrane(retentatedesired)Pressure:3447kPa(500psi;34bar)Applications:demineralizationofwhey,UFpermeateorretentate;decoloringUltrafiltration&DiafiltrationMembranesize:10-2to10-1mmRemovessmallmolecules(retentatedesired)Lactose,minerals,bacteria,virusesandsmallermoleculesallowedthroughPressure:344to689kPa(50–100psi;3–6bar)Applications:fractionation,clarification,concentrationofmilkproteinsandwheyDFinvolvesadditionofwaterduringUFasanadditionalwashstepMicrofiltrationMembranesize:10-1to101

mmRemovesbacteria(permeatedesired)Water,minerals,lactose,someproteinsandsmallercomponentsallowedthrough Pressure:69to344kPa(10–50psi;1–3bar)Applications:clarification,coldsterilization,concentration,proteinfractionationTraditionalfiltrationMembranesize:greaterthan10mmRemovescellularandmicroparticulatematterSediment,cheesefines,hairPressure:atmosphericApplications:filtrationofmilkbeforeitentersabulktankorprocessinglineSources:Osmonics,Inc.,FundamentalsofDairyChemistry,DairyProcessingHandbookEvaporationPurposeReducecostofdryingInducecrystallization(lactose)ReducecostsforstorageandtransportationReducewateractivityRecoverby-productsof“waste”streams(whey)GEAProcessEngineeringInc.FallingfilmevaporatorsMilkorwheyisintroducedattopofaverticalchamberWalls,tubesorplatesareheatedwithsteamProductflowsdownthehotsurfaceandformsaconcentratedfilmVacuumispulledonchambersovaporsaredrivenoffandtemperaturedoesnotexceed100CConcentratedproductexitsthebottomMoistureisreducedto~45-55%HighQuality(HQ)MILKStandardizeHeattreatment(notsterilized,negativephosphatase/lipase)EvaporationWaterSugarAdditionStandardizeOptionalingredientadditionCoolingandcrystallizationPackageSWEETENEDCONDENSEDMILKHQMILKStandardizeHeattreatment(preheat)EvaporationWaterHomogenizeStandardizeOptionalingredientadditionFillcansandsealSterilizeEVAPORATEDMILK

ConcentrateddairyproductsDryingPurposeSimilartoevaporationbutbenefitismorepronouncedFinalproductmoisturedoesnotexceed5%SpraydryingDispersionofconcentrateintofinedropletsMixingofconcentrateintoastreamofhotair,whichquicklyevaporatesthewaterSeparationoftheparticlesfromthedryingairdirectlyintobag,orcombinedwithfluidizedbeddryingInstantizingProcessusedtomakeapowderedproduct“instant”ImpovesreconstitutionpropertiesApplications:chocolatedrinks,coffeewhiteners,infantformula,nonfatdrymilk,proteindrinksNaturally,wholemilkpowderformsabarriertopreventliquidpenetrationNaturally,proteinpowdersre-wetsurfacequickly;preventsliquidpenetrationInstantizingAgglomerationSurfacesofdrypowderarere-wetbyanatomizerMoistureisraisedtoabout8%Impartsacoarse,porousstructuretopowdersSnowflake-likeagglomeratessticktogetherCapillaryforceswithincavitiesallowliquidtopenetrateLecithinationPowderiscoatedwithasurfaceactiveagentDrydairyproducts

HQMILKStandardizeHomogenize(optional)Heattreatment(notsterilized,negativephosphatase/lipase)EvaporationWaterDrying WaterPackageDRYWHOLEMILKHQMILKStandardize(clarify/separate)Homogenize(optional)Heattreatment(notsterilized,negativephosphatase/lipase)EvaporationWaterDrying WaterPackageNONFATDRYMILKDrywheyproductsIII.MilkPowdersIV.YogurtU.S.RegulationsCodeofFederalRegulationsspecifiesyogurtMustcontainLactobacillusdelbrueckiissp.bulgaricusStreptococcusthermophilusMustcontainnotlessthan8.25%MSNF0.90%TAYogurtingredientsHighqualitymilkMilkfatRegularyogurt(3.25%)Lowfatyogurt(0.5to2%)Nonfatyogurt(Lessthan0.5%)Sweeteners(<12%topreventcultureinhibition)Sugar,cornsyrup,highintensitysweetenersStabilizersGelatin,modifiedfoodstarch(cornortapioca),agar,wheyprotein,carrageenan,guargum,carboxy-methylcellulose,pectinCulturesStarters,probioticbacteriaYogurtprocessingStrictqualityandsanitationpracticesessentialMixingofingredients(exceptcultures)Pasteurization&homogenizationHigherthanstandard(83to89°Cfor30minor89to95°Cfor15to60sec)PreventssyneresisCoolingtoabout40°CInoculation(1:1ratioofL.bulgaricusandS.thermophilus)AdditionofprobioticbacteriamaybebeforethisstepYogurtprocessingIncubation35to40°CfavorsS.thermophilus(acidproduction)40to45°CfavorsL.bulgaricus(acetaldehydeproduction)CoolingafterTAreaches0.9%(pHabout4.5)Additionoffruits/flavors;blendingPackaginganddistributionVariousyogurtproductionoptionsProbioticDefinitionPro“for”-bios“l(fā)ife”Livemicroorganisms,whichwhenadministeredinadequateamounts,conferhealthbenefitsonthehost(FAO/WHO)CommonlylacticacidbacteriaBifidobacteria(manyspecies,strains)Lactobacillus(manyspecies,strains)Lactococcuslactis(afewstrains)Streptococcusthermophilus(afewstrains)Propionibacterium(afewstrains)Enterococcus(afewstrains;notalwaysconsideredprobiotic)Someotherbacteria(notalwaysprobiotic—usecaution!)BacilluscoagulansEscherichiacoliNissle1917Someyeast((notalwaysprobiotic—usecaution!)SaccharomycesboulardiiSanders.2003.NutritionReviews.61(3):91-99CurrentClimateProbioticproductsavailableinmanyformsPillsPowdersInfantformulaFoodsSalesofprobioticfoodsandbeveragesintheUS(TheNielsenCo.)$1.26billionforthe52weeksendingJune12,2010Upfrom1.2billionin2009Upfrom1.06billionin2008Photo:Prof.LorenzoMorelli,InstitutodiMicrobiologia,Piacenza,ItalyHowMayProbioticsHelpUs?EasediarrheaInhibittoothdecayAidinlactoseintolerance/malabsorption/maldigestionInhibitcancerEnhanceimmunesystemEaseasthmaandallergyReducecholesterollevelsReducebloodpressureManageulcerativecolitisManageurinarytractinfectionsArvolaetal.1999;Donnet-Hughesetal.1999;GillandGuarner2004;Linetal.1991;Madsenetal.2001;Sanders2003Howmaytheyhelpus?DecreaseluminalpH(shortchainfattyacids)DelivermicrobiallactasetosmallintestineRendervitalnutrientsunavailabletopathogensAltertheredoxpotentialoftheenvironmentProducehydrogenperoxideProducebacteriocinsorotherinhibitorysubstancesTranslocation/barriereffectsCellcomponentsoffermentation-derivedpeptidesactasACEinhibitorsAlterationofpopulations,activities,orabilityofcompetingmicrofloratoadheretoteethorgastrointestinalliningCausecell-mediatedimmuneresponsesKailasapathyandChin2000;Gilletal2001;Isolaurietal.2000;Sanders,2003DominantmicrobialspeciesinvariousregionsofthehumanGItractThehumangutcontains10Xmorebacteria(1014)thaneukaryoticcellsinthebody.About99%ofthetotalhumanmicrobiotaconsistofonly30-40differentbacterialgenera,Relativeproportionsvarybydiet,sex,age,etc.Thesemicroorganismsmayhaveanegative,neutralorpositiveeffectConway1995;GillandGuarner2004;Muelleretal.2006;Garcia-Albiachetal.2007DominantmicrobialspeciesinvariousregionsofthehumanGItractSartour.2008.Gastroenterology.134:577-594RequirementstobeconsideredProbioticMetabolicallystableandactiveinthefoodproductSurvivepassagethroughthegastrointestinal(GI)tractAdhereandcolonizetheGItractBenefitthehostPhoto:Prof.LorenzoMorelli,InstitutodiMicrobiologia,Piacenza,ItalyBut…Althoughtherearehundredsofpeer-reviewedpublicationsonprobiotics,onlyafewstrainsactingonafewclinicaltargetshavethestatusof“establishedeffects”ThereishugediversityincolonizingmicroorganismsGeneralizationsaboutprobioticscanbemisleadingSanders.2003.NutritionReviews.61(3):91-99BacteriadifferatthestrainlevelGenera(Lactobacillus,Bifidobacterium)Speciesofeachgenus(L.acidophilus,L.casei)Strainsofeachspecies(L.caseiShirota,L.caseiDN-114001)Izquierdoetal.2008.Curr.Microbiol.56:613-618.AdhesionabilityofdifferentB.longumstrainstomucinglycoproteinsAdditionally…Majorgapsexistinourknowledgeregarding:MechanismsbywhichprobioticsmodulatevariousphysiologicalfunctionsOptimumdoseOptimumfrequencyDurationoftreatmentCurrentrecommendationbytheInternationalDairyFederation:Tobenefitahost,fermentedproductsshouldcontainatleast107viableprobioticbacteriapergormLattimeofconsumption.BacteriagrantedstatusasactiveingredientsinFoodsforSpecifiedHealthUseinJapan*L.acidophilusSBT-2062L.paracaseiShirota(YIT9018)L.rhamnosusGG(ATTCC53103)B.longumBB536B.longumSBT-2928B.brevestrainYakult*anapprovalasdocumentedfunctionalfoodbytheMinistryofHealthinJapanSanders.2003.LegalRequirementstobecalled“Probiotic”FAO/WHOGuidelines2002StrainidentificationbyphenotypicandgenotypicmethodsSafetyassessment(invitroand/oranimal)Functionalcharacterization(invitro,animalstudies)Double-blind,randomized,placebo-controlledhumantrialorotherappropriatedesignwithsamplesizeandprimaryoutcomeappropriatetodetermineifstrain/productisefficaciousPreferably2ndindependentstudytoconfirmfindingsEffectivenesstrialtocompareprobioticswithstandardtreatmentofaspecificconditionLabeling:contents,minimumnumberofviablemicrobesatendofshelflife,properstorageconditions,contactdetailsChallengesofprobioticfoodproduction BacteriadifferatthestrainlevelMostinhibitedbyoxygen/dissolvedoxygenSensitivetohydrogenperoxideHarmedatextremetemperaturesPronetocellwalldamageInhibitedbylowpH/highacidityOthersensitivities...FoodScienceUsedtoAidProbioticFoodProduction AdditionofprebioticsInulin,galactooligosaccharides,etc.UseofbuffersWheyprotein,citrates,phosphates,etc.Carefulselectionofacid-andbile-resistantmicroorganismsUseofoxygen-impermeablecontainersTwo-stepfermentationAdditionoflyoprotectantsGlycerol,saccharose,calciumcarbonate,etc.MicroencapsulationChallengestoMakingProbiotics

HealthClaimsSometraitsseemtobesharedwithinspeciesLactaseproductionbyS.thermophilusandL.bulgaricusstrainsReuterinproductionbyL.reuteriAcetateproductionbyallspeciesofBifidobacteriumButexpressioninvivomaydiffer,requiringneedtoverifyfunctionalityintargethostSanders.2009.SupplySideWestoralpresentation.WhyareProbioticsHealthClaimsnotAcceptable?Bacteriadifferatthestrainlevel,andhumanstudiesareneededtocomparedifferentstrainsofthesamespecies…

…thus,itmakessensethatwecannotmakeblanketstatementsaboutthebenefitsofspeciesSanders.2009.SupplySideWestoralpresentation.RequirementstoMakeProbiotics

HealthClaimsGenericclaimsarenotjustifiedforprobioticproductsDocumentationofhealthbenefitsmustbedoneonthespecificstrain(s)beingsoldReviewarticlesthatdiscussstudiesdoneondifferentprobioticsarenotsufficienttosubstantiateeffectsofanuntestedstrainEvidencethatmorethanonestrainhavesimilareffectsisnotproofthatallstrainsw