ThenewdefinitionofdietaryfibreintroducedbyCodexAlimentariusin2008includesresistantstarchandtheoptiontoincludenon-digestIBLeoligosaccharides.Implementationofthisdefinitionrequirednewmethodology.AnintegratedtotaldietaryfibremethodwasevaluatedandacceptedbyAOACInternationalandAACCInternational(AOACMethods2009.01and2011.25;AACCMethod32–45.01and32–50.01,andrecentlyadoptedbyCodexAlimentariusasaTypeIMethod.However,inapplicationofthemethodtoadiverserangeoffoodsamplesandparticularlyfoodingredients,somelimitationshavebeenidentified.Oneoftheongoingcriticismsofthismethodwasthatthetimeofincubationwithpancreaticα-amylase/amyloglucosidasemixturewas16 h,whereasthetimeforfoodtotransitthroughthehumansmallintestinewaslikelytobeapproximately4 h.Inthecurrentwork,weuseanincubationtimeof4 h,andhaveevaluatedincubationconditionsthatyieldresistantstarchanddietaryvaluesinlinewithileostomyresultswithinthistimeframe.Problemsassociatedwithproduction,hydrolysisandchromatographyofvariousoligosaccharideshavebeenaddressedresultinginamorerapidprocedurethatisdirectlyapplicabletoallfoodsandfoodingredientscurrentlyavailable.

Interestindietaryfibreisundergoingadramaticrevival,thanksinparttotheintroductionofnewcarbohydratesasdietaryfibrecomponents.Muchemphasisisbeingplacedondetermininghowmuchfibreispresentinafood.Linkingaparticularamountoffibretoaspecifichealthbenefitisnowanimportantareaofresearch.Theterm"dietaryfibre"firstappearedin1953,andreferredtohemicelluloses,cellulosesandlignin(Theandere/tf/.1995).Trowell(1974)recommendedthistermasareplacementforthenolongeracceptableterm"crudefibre".Burkitt(1995)haslikenedtheinterestindietaryfibretothegrowthofariverfromitsfirsttrickletoamightytorrentHeobservesthatdietaryfibre"wasfirstviewedasmerelythelessdigestibleconstituentoffoodwhichexertsalaxativeactionbyirritatingthegut",thusacquiringthedesignation"roughage"-atermlaterreplacedby"crudefibre"andultimatelyby"dietaryfibre".Variousdefinitionsofdietaryfibrehaveappearedovertheyears,partlyduetothevariousconceptsusedinderivingtheterm(i.e.originofmaterial,resistancetodigestion,fermentationinthecolon,etc.),andpartlytothedifficultiesassociatedwithitsmeasurementandlabelling(Mongeauetal.1999).Theprincipalcomponentsofdietaryfibre,astrADItionallyunderstood,arenon-starchpolysaccharides(whichinplantfibreareprincipallyhemicellulosesandcelluloses),andthenon-carbohydratephenoliccomponents,cutin,suberinandwaxes,withwhichtheyareassociatedinnature.In1976,thedefinitionofdietaryfibrewasmodifiedtoincludegumsandsomepecticsubstances,basedontheresistancetodigestionofthesecomponentsintheupperintestinaltract.Forthepurposesoflabelling,Englystetal.(1987)proposedthatdietaryfibrebedefinedas"non-starchpolysaccharides(NSP)inthedietthatarenotdigestedbytheendogenoussecretionsofthehumandigestivetract".MethodswereconcurrentlydevelopedtospecificallymeasureNSP(Englystetal.1994).

Interestindietaryfibreisundergoingadramaticrevivalthanksinparttotheintroductionofnewcarbohydratesasdietaryfibrecomponents.Muchemphasisisbeingplacedondetermininghowmuchfibreispresentinafood.Linkingaparticularamountoffibretoaspecifichealthbenefitisnowanimportantareaofresearch.TotalDietaryFibre.Theterm“dietaryfibre”firstappearedin1953andreferredtohemicelluloses,cellulosesandlignin(1).In1974,Trowell(2)recommendedthistermasareplacementforthenolongeracceptableterm“crudefibre”Burkitt(3)haslikenedtheinterestindietaryfibretothegrowthofariverfromitsfirsttrickletoamightytorrent.Heobservesthatdietaryfibre“wasviewedasmerelythelessdigestibleconstituentoffoodwhichexertsalaxativeactionbyirritatingthegut“thusacquiringthedesignation“roughage”atermwhichwaslaterreplacedby“crudefibre”andultimatelyby“dietaryfibre”Variousdefinitionsofdietaryfibrehaveappearedovertheyears,partlyduethevariousconceptsusedinderivingtheterm(i.e.originofmaterial,resistancetodigestion,fermentationinthecolonetc.),andpartlytothedifficultiesassociatedwithitsmeasurementandlabelling(4).Theprinciplecomponentsofdietaryfibre,astraditionallyunderstood,arenon-starchpolysaccharides,whichinplantfibreareprincipallyhemicellulosesandcelluloses,andthenon-carbohydratephenoliccomponents,cutin,suberinandwaxeswithwhichtheyareassociatedinNature.

Dietaryfiberismainlycomposedofplantcellwallpolysaccharidessuchascellulose,hemicellulose,andpecticsubstances,butitalsoincludesligninandotherminorcomponents(1).Basically,itcoversthepolysaccharidesthatarenothydrolyzedbytheendogenoussecretionsofthehumandigestivetract(2,3).Thisdefinitionhasservedasthetargetforthosedevelopinganalyticalproceduresforthemeasurementofdietaryfiberforqualitycontrolandregulatoryconsiderations(4).Mostproceduresforthemeasurementoftotaldietaryfiber(TDF),orspecificpolysaccharidecomponents,eitherinvolvesomeenzymetreatmentstepsoraremainlyenzyme-based.InthedevelopmentofTDFproceduressuchastheProskymethod(AOACInternational985.29,AACC32—05)(5),theUppsalamethod(AACC32-25)(6),andtheEnglystmethod(7),theaimwastoremovestarchandproteinthroughenzymetreatment,andtomeasuretheresidueasdietaryfiber(afterallowingforresidual,undigestedproteinandash).Dietaryfiberwasmeasuredeithergravimetricallyorbychemicalorinstrumentalprocedures.Manyoftheenzymetreatmentstepsineachofthemethods,particularlytheprosky(5)andtheUppsala(6)methodsareverysimilar.Asanewrangeofcarbohydratesisbeingintroducedaspotentialdietaryfibercomponents,theoriginalassayprocedureswillneedtobereexamined,andinsomecasesslightlymodified,toensureaccurateandquantitativemeasurementofthesecomponentsandofTDF.These“new”dietaryfibercomponentsincluderesistantnondigestibleoligosaccharides;nativeandchemicallymodifiedpolysaccharidesofplantandalgalorigin(galactomannan,chemicallymodifiedcelluloses,andagarsandcarrageenans);andresistantstarch.Tomeasurethesecomponentsaccurately,thepurity,activity,andspecificityoftheenzymesemployedwillbecomemuchmoreimportant.Aparticularexampleofthisisthemesurementoffructan.Thiscarbohydrateconsistsofafractionwithahighdegreeofpolymerization(DP)thatisprecipitatedinthestandardProskymethod(5,8)andalowDPfractionconsequentlyisnotmeasured(9).Resistantstarchposesaparticularproblem.Thiscomponentisonlypartiallyresistanttodegradationbyα-amylase,sothelevelofenzymeusedandtheincubationconditions(timeandtemperature)arecritical.

Astudywasmadeoftheeffectoftheactivityandpurityofenzymesintheassayoftotaldietaryfiber(AOACMethod985.29)andspecificdietaryfibercomponents:resistantstarch,fructan,andβ-glucan.Inthemeasurementoftotaldietaryfibercontentofresistantstarchsamples,theconcentrationofα-amylaseiscritical;however,variationsinthelevelofamyloglucosidasehavelittleeffect.Contaminationofamyloglucosidasepreparationswithcellulasecanresultinsignificantunderestimationofdietaryfibervaluesforsamplescontainingβ-glucan.Pureβ-glucanandcellulasepurifiedfromAspergillusnigeramyloglucosidasepreparationswereusedtodetermineacceptablecriticallevelsofcontamination.Sucrose,whichinterfereswiththemeasurementofinulinandfructooligosaccharidesinplantmaterialsandfoodproducts,mustberemovedbyhydrolysisofthesucrosetoglucoseandfructosewithaspecificenzyme(sucrase)followedbyborohydridereductionofthefreesugars.Unlikeinvertase,sucrasehasnoactiononlowdegreeofpolymerization(DP)fructooligosaccharides,suchaskestoseorkestotetraose.Fructanishydrolyzedtofructoseandglucosebythecombinedactionofhighlypurifiedexo-andendo-inulinases,andthesesugarsaremeasuredbythep-hydroxybenzoicacidhydrazidereducingsugarmethod.Specificmeasurementofβ-glucanincerealflourandfoodextractsrequirestheuseofhighlypurifiedendo-1,3:1,4β-glucanaseandA.nigerβ-glucosidase.β-glucosidasefromalmondsdoesnotcompletelyhydrolyzemixedlinkageβ-glucooligosaccharidesfrombarleyoroatβ-glucan.Contaminationoftheseenzymeswithstarch,maltosaccharide,orsucrose-hydrolyzingenzymesresultsinproductionoffreeglucosefromasourceotherthanβ-glucan,andthusanoverestimationofβ-glucancontent.Theglucoseoxidaseandperoxidaseusedintheglucosedeterminationreagentmustbeessentiallydevoidofcatalaseandα-andβ-glucosidase.

Enzymeactivityandpurityofthesetopics,theeasiesttodealwithistheimportanceofenzymepurityandactivity.Asascientistactivelyinvolvedinpolysaccharideresearchoverthepast25years,Ihavecometoappreciatetheimportanceofenzymepurityandspecificityinpolysaccharidemodificationandmeasurement(7).Thesefactorstranslatedirectlytodietaryfiber(DF)methodology,becausethemajorcomponentsofDFarecarbohydratepolymersandoligomers.ThecommitteereportpublishedintheMarchissueofCerealFOODSWORLDrefersonlytothemethodologyformeasuringenzymepurityandactivity(8)thatleduptheAOACmethod985.29(2).Inthisworkenzymepuritywasgaugedbythelackofhydrolysis(i.e.,completerecovery)ofaparticularDFcomponent(e.g.β-glucan,larchgalactanorcitruspectin).EnzymeactivitywasmeasuredbytheABIlitytocompletelyhydrolyzerepresentativestarchandprotein(namelywheatstarchandcasein).Theserequirementsandrestrictionsonenzymepurityandactivitywereadequateatthetimethemethodwasinitiallydevelopedandservedasausefulworkingguide.However,itwasrecognizedthattherewasaneedformorestringentqualitydefinitionsandassayproceduresforenzymesusedinDFmeasurements.

The"goldstandard"methodforthemeasurementoftotaldietaryfibreisthatoftheAssociationofOfficialAnalyticalChemists(2000;method985.29).Thisprocedurehasbeenmodifiedtoallowmeasurementofsolubleandinsolubledietaryfibre,andbuffersemployedhavebeenimproved.However,therecognitionofthefactthatnon-digestibleoligosaccharidesandresistantstarchalsobehavephysiologicallyasdietaryfibrehasnecessitatedare-examinationofthedefinitionofdietaryfibre,andinturn,are-evaluationofthedietaryfibremethodsoftheAssociationofOfficialAnalyticalChemists.Withthisrealisation,theAmericanAssociationofCerealChemistsappointedascientificreviewcommitteeandchargeditwiththetaskofreviewingand,ifnecessary,updatingthedefinitionofdietaryfibre.Itorganisedvariousworkshopsandacceptedcommentsfrominterestedpartiesworldwidethroughaninteractivewebsite.Morerecently,the(US)FoodandNutritionBoardoftheInstituteofHealth,NationalAcademyofSciences,undertheoversightoftheStandingCommitteeontheScientificEvaluationofDietaryReferenceIntakes,assembledapaneltodevelopaproposeddefinition(s)ofdietaryfibre.Variouselementsofthesedefinitionswereinagreement,butnotall.Whatwasclearfrombothreviewsisthatthereisanimmediateneedtore-evaluatethemethodsthatareusedfordietaryfibremeasurementandtomakeappropriatechangeswhererequired,andtofindnewmethodstofillgaps.Inthispresentation,the"stateoftheart"inmeasurementoftotaldietaryfibreanddietaryfibrecomponentswillbedescribedanddiscussed,togetherwithsuggestionsforfutureresearch.

Withtherecognitionthatresistantstarch(RS)andnondigestibleoligosaccharides(NDO)actphysiologicallyasdietaryfiber(DF),aneedhasdevelopedforspecificandreliableassayproceduresforthesecomponents.TheabilityofAOACDFmethodstoaccuratelymeasureRSisdependentonthenatureoftheRSbeinganalyzed.Ingeneral,NDOarenotmeasuredatallbyAOACDFMethods985.29or991.43,theoneexceptionbeingthehighmolecularweightfractionoffructo-oligosaccharides.ValuesobtainedforRS,ingeneral,arenotingoodagreementwithvaluesobtainedbyinvitroproceduresthatmorecloselyimitatetheinvivosituationinthehumandigestivetract.Consequently,specificmethodsfortheaccuratemeasurementofRSandNDOhavebeendevelopedandvalidatedthroughinterlaboratorystudies.Inthispaper,modificationstoAOACfructanMethod999.03toallowaccuratemeasurementofenzymicallyproducedfructo-oligosaccharidesaredescribed.SuggestedmodificationstoAOACDFmethodstoensurecompleteremovaloffructanandRS,andtosimplifypHadjustmentbeforeamyloglucosidaseaddition,arealsodescribed.

TheCodexCommitteeonMethodsofAnalysisandSamplingrecentlyrecommended14methodsformeasurementofdietaryfiber,eightofthesebeingtypeImethods.OfthesetypeImethods,AACCInternationalApprovedMethod32-45.01(AOACmethod2009.01)istheonlyprocedurethatmeasuresallofthedietaryfibercomponentsasdefinedbyCodexAlimentarius.OthermethodssuchastheProskymethod(AACCIApprovedMethod32-05.01)givesimilaranalyticaldataforthehigh-molecular-weightdietaryfibercontentsoffoodandvegetableproductslowinresistantstarch.Inthecurrentwork,AACCIApprovedMethod32-45.01hasbeenmodifiedtoallowaccuratemeasurementofsampleshighinparticularfructooligosaccharides:forexample,fructotriose,which,intheHPLCsystemused,chromatographsatthesamepointasdisaccharides,meaningthatitiscurrentlynotincludedinthemeasurement.Incubationoftheresistantoligosaccharidesfractionwithsucrase/β-galactosidaseremovesdisaccharidesthatinterferewiththequantitationofthisfraction.Thedietaryfibervalueforresistantstarchtype4(RS₄),variessignificantlywithdifferentanalyticalmethods,withmuchlowervaluesbeingobtainedwithAACCIApprovedMethod32-45.01thanwith32-05.01.ThisdifferenceresultsfromthegreatersusceptibilityofRS₄tohydrolysisbypancreaticα-amylasethanbybacterialα-amylase,andalsoagreatersusceptibilitytohydrolysisatlowertemperatures.OnhydrolysisofsampleshighinstarchintheassayformatofAACCIApprovedMethod32-45.01(AOACmethod2009.01),resistantmaltodextrinsareproduced.Themajorcomponentisaheptasaccharidethatishighlyresistanttohydrolysisbymostofthestarch-degradingenzymesstudied.However,itishydrolyzedbythemaltase/amyloglucosidase/isomaltaseenzymecomplexpresentinthebrushborderliningofthesmallintestine.Asaconsequence,AOACmethods2009.01and2011.25(AACCIApprovedMethods32-45.01and32-50.01,respectively)mustbeupdatedtoincludeanadditionalincubationwithamyloglucosidasetoremovetheseoligosaccharides.

Amethodisdescribedforthemeasurementofdietaryfibre,includingresistantstarch(RS),non-digestibleoligosaccharides(NDO)andavailablecarbohydrates.Basically,thesampleisincubatedwithpancreaticα-amylaseandamyloglucosidaseunderconditionsverysimilartothosedescribedinAOACOfficialMethod2002.02(RS).Reactionisterminatedandhighmolecularweightresistantpolysaccharidesareprecipitatedfromsolutionwithalcoholandrecoveredbyfiltration.RecoveryofRS(formostRSsources)isinlinewithpublisheddatafromileostomystudies.Theaqueousethanolextractisconcentrated,desaltedandanalysedforNDObyhigh-performanceliquidchromatographybyamethodsimilartothatdescribedbyOkuma(AOACMethod2001.03),exceptthatforlogisticalreasons,D-sorbitolisusedastheinternalstandardinplaceofglycerol.Availablecarbohydrates,definedasD-glucose,D-fructose,sucrose,theD-glucosecomponentoflactose,maltodextrinsandnon-resistantstarch,aremeasuredasD-glucoseplusD-fructoseinthesampleafterhydrolysisofoligosaccharideswithamixtureofsucrase/maltaseplusβ-galactosidase.

Anintegratedtotaldietaryfibre(TDF)method,consistentwiththerecentlyacceptedCODEXdefinitionofdietaryfibre,hasbeendeveloped.TheCODEXCommitteeonNutritionandFoodsforSpecialDietaryUses(CCNFSDU)hasbeendeliberatingforthepast8yearsonadefinitionfordietaryfibrethatcorrectlyreflectsthecurrentconsensusthinkingonwhatshouldbeincludedinthisdefinition.Asthisdefinitionwasevolving,itbecameevidenttousthatneitherofthecurrentlyavailablemethodsforTDF(AOACOfficialMethods985.29and991.43),noracombinationoftheseandothermethods,couldmeettheserequirements.Consequently,wedevelopedanintegratedTDFprocedure,basedontheprincipalsofAOACOfficialMethods2002.02,991.43and2001.03,thatiscompliantwiththenewCODEXdefinition.Thisprocedurequantitateshigh-andlow-molecularweightdietaryfibresasdefined,givinganaccurateestimateofresistantstarchandnon-digestibleoligosaccharidesalsoreferredtoaslow-molecularweightsolubledietaryfibre.Inthispaper,themethodisdiscussed,modificationstothemethodtoimprovesimplicityandreproducibilityaredescribed,andtheresultsofthefirstroundsofinterlaboratoryevaluationarereported.

Amethodforthedeterminationoftotaldietaryfiber(TDF),asdefinedbytheCODEXAlimentarius,wasvalidatedinfoods.BasedupontheprinciplesofAOACOfficialMethods^SM985.29,991.43,2001.03,and2002.02,themethodquantitateshigh-andlow-molecular-weightdietaryfiber(HMWDFandLMWDF,respectively).In2007,McClearydescribedamethodofextendedenzymaticdigestionat37°CtosimulatehumanintestinaldigestionfollowedbygravimetricisolationandquantitationofHMWDFandtheuseofLCtoquantitatelow-molecular-weightsolubledietaryfiber(LMWSDF).Themethodthusquantitatesthecompleterangeofdietaryfibercomponentsfromresistantstarch(byutilizingthedigestionconditionsofAOACMethod2002.02)todigestionresistantoligosaccharides(byincorporatingthedeionizationandLCproceduresofAOACMethod2001.03).ThemethodwasevaluatedthroughanAOACcollaborativestudy.Eighteenlaboratoriesparticipatedwith16laboratoriesreturningvalidassaydatafor16testportions(eightblindduplicates)consistingofsampleswitharangeoftraditionaldietaryfiber,resistantstarch,andnondigestibleoligosaccharides.Thedietaryfibercontentoftheeighttestpairsrangedfrom11.57to47.83.DigestionofsamplesundertheconditionsofAOACMethod2002.02followedbytheisolationandgravimetricproceduresofAOACMethods985.29and991.43resultsinquantitationofHMWDF.ThefiltratefromthequantitationofHMWDFisconcentrated,deionized,concentratedagain,andanalyzedbyLCtodeterminetheLMWSDF,i.e.,allnondigestibleoligosaccharidesofdegreeofpolymerization3.TDFiscalculatedasthesumofHMWDFandLMWSDF.Repeatabilitystandarddeviations(S_r)rangedfrom0.41to1.43,andreproducibilitystandarddeviations(S_R)rangedfrom1.18to5.44.Theseresultsarecomparabletootherofficialdietaryfibermethods,andthemethodisrecommendedforadoptionasOfficialFirstAction.

Amethodforthedeterminationofinsoluble(IDF),soluble(SDF),andtotaldietaryfiber(TDF),asdefinedbytheCODEXAlimentarius,wasvalidatedinfoods.BasedupontheprinciplesofAOACOfficialMethods^SM985.29,991.43,2001.03,and2002.02,themethodquantitateswater-insolubleandwater-solubledietaryfiber.ThismethodextendsthecapabilitiesofthepreviouslyadoptedAOACOfficialMethod2009.01,TotalDietaryFiberinFoods,Enzymatic-Gravimetric-LiquidChromatographicMethod,applicabletoplantmaterial,foods,andfoodingredientsconsistentwithCODEXDefinition2009,includingnaturallyoccurring,isolated,modified,andsyntheticpolymersmeetingthatdefinition.ThemethodwasevaluatedthroughanAOAC/AACCcollaborativestudy.Twenty-twolaboratoriesparticipated,with19laboratoriesreturningvalidassaydatafor16testportions(eightblindduplicates)consistingofsampleswitharangeoftraditionaldietaryfiber,resistantstarch,andnondigestibleoligosaccharides.Thedietaryfibercontentoftheeighttestpairsrangedfrom10.45to29.90%.DigestionofsamplesundertheconditionsofAOAC2002.02followedbytheisolation,fractionation,andgravimetricproceduresofAOAC985.29(anditsextensions991.42and993.19)and991.43resultsinquantitationofIDFandsolubledietaryfiberthatprecipitates(SDFP).Thefiltratefromthequantitationofwater-alcohol-insolubledietaryfiberisconcentrated,deionized,concentratedagain,andanalyzedbyLCtodeterminetheSDFthatremainssoluble(SDFS),i.e.,alldietaryfiberpolymersofdegreeofpolymerization=3andhigher,consistingprimarily,butnotexclusively,ofoligosaccharides.SDFiscalculatedasthesumofSDFPandSDFS.TDFiscalculatedasthesumofIDFandSDF.Thewithin-laboratoryvariability,repeatabilitySD(S_r),forIDFrangedfrom0.13to0.71,andthebetween-laboratoryvariability,reproducibilitySD(s_R),forIDFrangedfrom0.42to2.24.Thewithin-laboratoryvariabilitys_rforSDFrangedfrom0.28to1.03,andthebetween-laboratoryvariabilitysRforSDFrangedfrom0.85to1.66.Thewithin-laboratoryvariabilitysrforTDFrangedfrom0.47to1.41,andthebetween-laboratoryvariabilitys_RforTDFrangedfrom0.95to3.14.Thisiscomparabletootherofficialandapproveddietaryfibermethods,andthemethodisrecommendedforadoptionasOfficialFirstAction.

AOACOfficialMethods2009.01and2011.25havebeenmodifiedtoallowremovalofresistantmaltodextrinsproducedonhydrolysisofvariousstarchesbythecombinationofpancreaticα-amylaseandamyloglucosidase(AMG)usedintheseassayprocedures.Themajorresistantmaltodextrin,6³,6⁵-di-α-D-glucosylmaltopentaose,ishighlyresistanttohydrolysisbymicrobialα-glucosidases,isoamylase,pullulanase,pancreatic,bacterialandfungalα-amylaseandAMG.However,thisoligosaccharideishydrolyzedbythemucosalα-glucosidasecomplexofthepigsmallintestine(whichissimilartothehumansmallintestine),andthusmustberemovedintheanalyticalprocedure.HydrolysisoftheseoligosaccharideshasbeenbyincubationwithahighconcentrationofapurifiedAMGat60°C.ThisincubationresultsinnohydrolysisorlossofotherresistantoligosaccharidessuchasFOS,GOS,XOS,resistantmaltodextrins(e.g.,Fibersol2)orpolydextrose.TheeffectofthisadditionalincubationwithAMGonthemeasuredleveloflowmolecularweightsolubledietaryfiber(SDFS)andoftotaldietaryfiberinabroadrangeofsamplesisreported.Resultsfromthisstudydemonstratethattheproposedmodificationcanbeusedwithconfidenceinthemeasurementofdietaryfiber.

Thisstudyaimedtoquantifythechangescausedbyvaryinggerminationconditionsonthecontentsofsomebioactivecompoundsinbarleyandoats.Samplesofthetwograinsweregerminatedattemperaturesbetween10and20°Cforaperiodof2–6days,usingatwo-dimensionalcentralcompositedesign.Thegerminationtemperaturehadonlyminoreffectincomparisonwiththegerminationtime.Slightchangesinthemineralcontentofthemaltswereobserved,mainlycausedbysteeping.Phytatehasbeenseenasananti-nutritionalcompound,asitcomplexesmineralsandlowerstheirbioavailability.Thephytatecontentinbarleymaltswasconsiderablylowerthaninthenativekernels.Variationsinthegerminationconditionsdidnothaveasignificanteffectonphytatecontent.Inoats,degradationofphytatewassignificantlyenhancedbyprolongingthegerminationperiod.Itwaspossibletoretaintheamountsofsolubledietaryfibre,whenshortgerminationperiodswereapplied.However,longgerminationperiodscausedanextensivebreakdownofsolubledietaryfibre,especiallybeta-glucan.Thecontentofinsolublefibre,however,wasincreasedbyapplyinglonggerminationperiodsforoatmalts.

Theschemeofflourmillinginmillcanbeexpressedindiagramasamillingflow.Therecanbedescribedaweightpartorpercentageofflourfromeverystageofbreaking,scratchandreduction.Thesimilarflowdiagramcanbedrawnexpressingtheashcontentineveryofflourstreamsofawholemillingflow.Amillingflowofbarleyisconsiderablydifferentfromthatofwheatandtosomepartalsofromryemillflow.Currently,high-yieldingnakedbarleycultivarsarepreferredintheWesternworld,andtheycanbeusedinproductswhereoutstandingstarchornon-starchpolysaccharidepropertiesarerequired.Theaimofthisworkwastoassessthemillingresultswithregardtotheyieldofsinglestreamsinconnectionwiththeirchemicalcomposition,especiallyβ-glucans(fiber)content.BarleysamplewasnakedbarleyofCzechoriginofcrop2010.Thebalancetablesshowingtheyieldofβ-glucansandashinsinglestreamswerecompiled.Resultingdatawerejudgedincomparisontothemillingflowwiththepurposetorecommendtheparametersandbeststreamsofmillingflowasasourceofspecialnutritionallylucrativeproducts.

Fruitbodies(separatelypileiandstems)ofmushroomsPleurotusostreatus(fourstrains)andPleurotuseryngiiwerecharacterisedasasourceofpolysaccharides.ThecontentsofglucansanddietaryfibresweredeterminedwithusingtherespectiveMegazymeenzymatickits.Enzymaticanalysisofthefruitbodiesconfirmedsignificantdifferencesinthecontentsofthesecomponentsamongthespeciesandstrains.Thestemscontainedmoreinsolubledietaryfibresthanthepileiinallthecasesandmoreβ-glucansinmostcases.However,relativelyhighcontentsofβ-glucan(20–50%ofdrymatter)couldbearesultofincompleteenzymatichydrolysisofinsolubleα-1,3-glucans.Nevertheless,lowfoodqualitystemsofmushroomsPleurotussp.couldbeavaluablesourceofcellwallglucansforthepreparationoffoodsupplements.

Thehypoglycemiceffectsofseveralinsolublefiber-richfractions(FRFs)includinginsolubledietaryfiber,alcohol-insolublesolid,andwater-insolublesolidisolatedfromthepomaceofAverrhoacarambolawereinvestigatedbysomeinvitromethods.ThisstudyevidencedthatthesethreeinsolubleFRFscouldeffectivelyadsorbglucose,retardglucosediffusion,postponethereleaseofglucosefromstarch,andinhibittheactivityofα-amylasetodifferentextents.Allofthesemechanismsmightcreateaconcertedfunctioninloweringtherateofglucoseabsorptionandasaresultdecreasethepostprandialserumglucoseconcentration.OurresultsrevealedthatthehypoglycemiceffectsoftheseinsolubleFRFsweresignificantly(P<0.05) stronger="" than="" that="" of="" cellulose.="" therefore,="" it="" was="" suggested="" that="" they="" could="" be="" incorporated="" as="" low-calorie="" bulk="" ingredients="" in="" high-fiber="" foods="" to="" reduce="" calorie="" level="" and="" help="" control="" blood="" glucose="" concentration.="">

Extrusioncookingiscommonlyusedintheproductionofsnacks.Inthepresentstudy,extrudateswerepreparedusingbarleyflouraloneandwiththeadditionofeitherpolydextrose(PD)orwheyproteinisolate(WPI)andbothPDandWPI.Independentprocessvariableswerewatercontentofthemass(17%,20%and23%),screwspeed(200,350and500rpm)andtemperatureofsection6anddie(110,130and150°C).Expansion,hardness,watercontent,porosityandchemicalcompositionoftheextrudateswereanalysed.HighlyporousandexpandedsnackproductswithhighdietaryfibreandproteincontentswereobtainedfrombarleyflourandWPIwhenwatercontentofmasswas17%,screwspeed500rpmandtemperatureofsection6anddie130°C.BarleyflouraloneorwithPDresultedinhardandnon-expandedextrudates.Expansionofextrudateswasstatisticallysignificantlyincreasedwithdecreasingwatercontentofthemassandincreasingscrewspeedinalltrials.

IntroductionThepresenceofresistantstarchinsamplescontainingnon-starchpolysaccharideshasalwaysbeenachallengetoenzymatictotalstarchandtotalfibreanalysis.ObjectiveandmethodsBasedonmicrowave-inducedpressuredisintegrationtechniquetheAssociationofOfficialAnalyticalChemistsmethodsforthedeterminationoftotalstarch(AOAC996.11)andtotaldietaryfibre(AOAC991.43)havebeenmodifiedtocompletelyeliminateundesirableresistantstarchfractionswithrespecttodigestionproceduresusingThermostableα-amylaseandamyloglucosidase.ResultsMicrowavetreatmentofhigh-amylosestarchsamplesresultedinexcellenttotalstarchrecoveryintheAssociationofOfficialAnalyticalChemistsstandardmethodno.996.11.AfterintegrationofmicrowavedisintegrationtechniqueintothetotaldietaryfibremethodAOAC911.43irradiationexperimentswithdifferentmodelmixturesconsistingofnon-starchpolysaccharidescomponentsandhigh-amylosestarchfractionsresultedinthecompleteeliminationofundesirableresistantstarchfractions.ConclusionThereforethemicrowavetechniquecanbeaveryefficientmeansfortheeliminationofresistantstarchandprovidesmorerealisticvaluesinanalyticaltotaldietaryfibreprocedureswithrespecttosamplescontainingcriticalenzymeresistantstarches.

Thisstudyaimedtoquantifythechangescausedbyvaryinggerminationconditionsonthecontentsofsomebioactivecompoundsinbarleyandoats.Samplesofthetwograinsweregerminatedattemperaturesbetween10and20°Cforaperiodof2–6days,usingatwo-dimensionalcentralcompositedesign.Thegerminationtemperaturehadonlyminoreffectincomparisonwiththegerminationtime.Slightchangesinthemineralcontentofthemaltswereobserved,mainlycausedbysteeping.Phytatehasbeenseenasananti-nutritionalcompound,asitcomplexesmineralsandlowerstheirbioavailability.Thephytatecontentinbarleymaltswasconsiderablylowerthaninthenativekernels.Variationsinthegerminationconditionsdidnothaveasignificanteffectonphytatecontent.Inoats,degradationofphytatewassignificantlyenhancedbyprolongingthegerminationperiod.Itwaspossibletoretaintheamountsofsolubledietaryfibre,whenshortgerminationperiodswereapplied.However,longgerminationperiodscausedanextensivebreakdownofsolubledietaryfibre,especiallybeta-glucan.Thecontentofinsolublefibre,however,wasincreasedbyapplyinglonggerminationperiodsforoatmalts.

InterestinTartarybuckwheatasacholesterol-loweringfunctionalfoodisincreasing.Thepresentstudywasto(i)investigatetherelativehypocholesterolemicactivityofTartarybuckwheatflourcomparedwiththatofwheatandriceflour;and(ii)studytheinteractionofthesethreeflourswithgeneexpressionofsteroltransportersandproteinsinvolvedincholesterolabsorption.Thirty-sixmalehamstersweredividedintofourgroupsfedeitherthecontroloroneofthreeexperimentaldietscontaining24%respectiveflour,foraperiodof6weeks.ResultsshowedthatTartarybuckwheatflourbutnowheatandricefloursreducedplasmatotalcholesterol(TC)andnon-high-densitylipoproteincholesterol(non-HDL)aswellashepaticcholesterolconcentrations.Comparedwiththatofwheatandriceflours,supplementationofTartarybuckwheatflourintodietledtogreaterneutralsterolexcretionandlessermRNAofintestinalNiemann-PickC1Like1(NPC1L1)andacyl-CoA:cholesterolacyltransferase2(ACAT2).ItwasthereforeconcludedthatTartarybuckwheatflourwashypocholesterolemicviainhibitionofcholesterolabsorption,mostlikelymediatedbydown-regulationofintestinalNPC1L1andACAT2.

Thereliabledeterminationofsoluble,insolubleandtotaldietaryfibreinbakedgoodsandcerealfloursisanimportantissueforresearch,nutritionallabellingandmarketing.Wecomparedtotaldietaryfibre(TDF)contentsofselectedcerealbasedfoodsdeterminedbyAOACMethod991.43andthenewAOACMethod2009.01.Fifteenbreadandbakeryproductswereincludedinthestudy.OurresultsshowedthatTDFvaluesofcerealproductsdeterminedbyAOACMethod2009.01werealwayssignificantlyhigherthanthosedeterminedbyAOACMethod991.43.ThiswasexplainedbytheinclusionoflowmolecularweightsolublefibrefractionsandresistantstarchfractionsintheTDFmeasurementbyAOAC2009.01.ThisdocumentsthatnutritionallabellingofcerealproductsposesthechallengehowtoupdateTDFdatainnutrientdatabasesinareasonabletimewithanacceptableexpenditure.

BACKGROUND:Barleyrootlets,amaltingby-product,arecurrentlydiscardedorusedasfodder.Inthisstudy,milledrootletsandLactobacillusplantarumFST1.7-fermentedrootletswereincorporatedintowheatbread.Theobjectivewastoformulateahigh-nutritionalternativetowholemealbreadswithimprovedtechnologicalattributes.RESULTS:Chemicalanalysesshowedthatrootletscontributenutrientsandbioactivecompounds,includingproteins,aminoacids,fattyacids,carbohydrates,dietaryfibre,polyphenolsandminerals.Rootletsareparticularlyrichinessentialaminoacids,especiallylysine,thetypicallylimitingessentialaminoacidofcereals.Additionally,rootletsofferpotentialdietaryfibrehealthbenefitssuchasprotectionagainstcardiovasculardisease,cancersanddigestivedisorders.CONCLUSION:Breadspreparedwitha(fermented)rootletinclusionlevelofupto10%comparedfavourablywithwholemealbreadsfromnutritive,technologicalandtexturalperspectives.Furthermore,theywerewellacceptedbysensorypanellists.Usingrootletsasafoodingredientwouldhavetheaddedbenefitofincreasingthismaltingby-product"smarketvalue.

BACKGROUND:Hazelnutskinistheperispermofthehazelnutkernel.Itisseparatedfromthekernelduringtheroastingprocessandisnormallydiscarded.Recentstudieshavereportedthathazelnutskinisarichsourceofdietaryfibreaswellasofnaturalantioxidantsowingtothepresenceofphenoliccompounds.Theaimofthisstudywastoassesstheuseofhazelnutskinsobtainedfromdifferentcultivarsforenhancingthenutritionalvalueoffresheggpasta.RESULTS:Skinsobtainedfromroastedhazelnutsoffourdifferentvarietieswereusedatthreeconcentrationsasaflourreplacementinfresheggpasta.Hazelnutskinconcentrationsignificantlyinfluencedallevaluatedphysicochemicalparametersaswellasconsumers"appreciationforthepasta,butsignificantdifferenceswerealsoobservedbetweenthefourvarieties.Althoughpastaproducedwith10and15%hazelnutskindisplayedthehighestcontentofpolyphenoliccompoundsandantioxidantactivityinvitro,pastacontaining5%Tombulhazelnutskinshowedmaximumconsumerpreference.CONCLUSION:Theresultsobtainedinthepresentstudyhighlightedthatitispossibletousehazelnutskininfreshpastaproductiontoobtainafortifiedfoodwithhighfibrecontentandantioxidantactivity.Thecharacteristicsoftheresultingpastawerestrictlycorrelatedwiththehazelnutvarietyusedforskinproductionand,ofcourse,withthepercentageofskinthatwasadded.

Fivepromisinglinesoffababean,whichincludestwolinei.e.2011215and2011410forgrainpurposewithyieldpotentialof>5.0t/haandthreepromisinglinesviz.,VFBP201302,VFBP201304andVFBP201306wereidentifiedforvegetablepurposeswithgreenpodyieldpotentialof21.51to23.54t/ha,suitableforEasternPartsofIndia.Thesedevelopedlineswereevaluatedalongwithnationalcheckvarietiesviz.,VikrantandPusaSumeetforitsnutritionalandantinutritionalquality.Developedlinescontainmoredietaryfiber,totalsolublesugar,totalstarch,phosphorus,ironmanganeseandzinc.Lessphytatewasfoundinthedevelopedlinesascomparetochecksvarieties.Maximum(1.56%)fatwasreportedinVFBP201304(ICNoICNo.0595988),Maximumdietaryfiber(13.49%)wasobtainedinthe2011410line(ICNo.0595986),however,minimumdietaryfiberwasfoundincheckvarietyVikrant(11.94).Similarly,minimum(0.10%)phytatewasnoticedintheline2011215(ICNo.0595985).

Theeffectofextrusiononcharacteristicsofdestarchedcornfiberwasinvestigated.Extrusionwasconductedatascrewspeedof300rpm,feedrateof100g/min,feedmoisturecontentof30%,melttemperatureof140°Canddiediameterof3mm.Afterextrusion,characteristicsofrawandextrudeddestarchedcornfiberwerecompared.RawandextrudeddestarchedcornfiberswereenzymaticallysaccharifiedandfermentedusingSaccharomycescerevisiae(ATCC24858).Extrusionpretreatmentresultedinlowcrystallinityindex,significantdecreaseindegreeofpolymerizationandmicrostructuredisruptionofdestarchedcornfiberforenzymaticsaccharification.Thisprovidesasignificantincreaseinxyloseyieldforfermentation.Significantincreaseinproteindigestibilityandfreeaminonitrogenwereadditionalbenefitsofextrusionforyeastnutrientinfermentation.Therefore,extrudeddestarchedcornfibersignificantlyincreased(p<0.05)=""ethanol=""yield=""(29.08=""g/l)=""and=""higher=""conversion=""(88.79%)=""by=""improving=""the=""physiochemical=""and=""functional=""properties=""for=""saccharification=""and=""fermentation.="">

Factorialexperimentaldesignwasusedtoinvestigatetheeffectsof:spongeproofingtime(min),spongeanddoughmixingtime(min),finalproofingtime(min),finalproofingtemperature(°C)andbakingtime(min)onAustraliansweetlupin-wheatbreadphysicalattributes.Factorialmodelsshowthatbreadspecificvolumewaspositivelyassociatedwithspongeanddoughmixingtime(P=0.01)andbakingtime(P=0.02).Crumbareawaspositivelyassociated(P=0.01)withspongeanddoughmixingtime.Finalproofingtimepositivelyinfluencedcellwallthickness(P<0.01)=""and=""cell=""diameter="">P<0.01)=""but=""negatively=""affected=""number=""of=""cells="">P<0.01).=""cell=""diameter=""was=""positively=""associated=""with=""baking=""time="">P=0.04),whilstnumberofcellswasnegativelyinfluencedbyspongeanddoughmixingtime(P=0.01).Instrumentalspringinesswaspositivelyassociatedwithspongeanddoughmixingtime(P=0.02).Spongeanddoughmixingandbakingtimeswerethetwomostsignificantprocessparametersaffectingthebreadphysicalqualityandhenceshouldbeoptimised.

Apigdigestibilitytrialwasconductedtoinvestigatetheeffectsoffermentationorextrusionofwheatbranincludedinabasaldietoncoefficientsoftotaltractapparentdigestibility(CTTAD)regardingdrymatter(DM),organicmatter(OM),crudeprotein(CP),crudefiber(CF),etherextract(EE),starch,energy(GE),phosphorus(P)andcalcium(Ca).Intheexperiment,9growingpigswereallocatedtoa3×3LatinsquaredesigntomeasuretheCTTADofthebasaldietcontainingdifferentmodifiedwheatbranvariants,andthereforetodemonstraterelativedifferencesintheCTTADamongthedietsasaresultofwheatbranmodification.Thewheatbranwasusedinnativeform(NWB),asfermentedbranensiledwithLactobacillusparacaseiandLactobacillusplantarum(FWB)andasextrudedwheatbran(EWB).Wheatbranvariantswereincludedat200gkg^-1inaphosphorusdeficientbasaldiet.TheobtainedresultsshowthattheCTTADofDMwasincreasedwhenfeedingthedietwithFWB(+2%,P<0.05) instead="" of="" nwb="" (0.87).="" likewise="" the="" cttad="" of="" om="" was="" also="" increased="" with="" fwb="" (+2%,="">P<0.05), compared="" to="" nwb="" (0.88).="" also="" the="" cttad="" of="" cf="" was="" improved="" with="" fwb="" and="" ewb="" (+9%,="">P<0.05), related="" to="" nwb="" (0.58).="" the="" cttad="" of="" ash="" was="" improved="" with="" fwb="" (+14%,="">P<0.05) compared="" to="" nwb="" (0.60).="" correspondingly,="" the="" cttad="" values="" of="" p="" and="" ca="" were="" also="" elevated="" when="" feeding="" the="" fwb="" diet.="" p-digestibility="" was="" increased="" in="" the="" fwb="" feeding="" group="" compared="" to="" those="" groups="" fed="" with="" nwb="" (+35%,="">P<0.05) and="" ewb="" (+53%,="">P<0.05). regarding="" the="" ca="" digestibility,="" similar="" results="" were="" obtained="">P<0.05). while="" the="" cttad="" of="" energy="" was="" increased="" in="" the="" fwb="" (+3%,="">P<0.05) and="" ewb="" (+2%,="">P<0.05) feeding="" groups="" compared="" to="" that="" of="" nwb="" (0.85),="" the="" n-balance="" and="" the="" cttad="" of="" starch="" were="" not="" affected="" by="" the="" treatments.="" nevertheless,="" the="" cttad="" of="" ee="" was="" enhanced="" in="" the="" fwb="" treatment="" group="" (+40%,="">P<0.05), and="" was="" also="" improved="" by="" extrusion="" (+30%,="">P<0.05)co