TheStarchDamagetestkitissuitableforthemeasurementandanalysisofstarchdamageincerealflours.Animprovedenzymicmethodforthemeasurementofstarchdamageinwheatflour.Gibson,T.S.,AlQalla,H.&McCleary,B.V.(1992).JournalofCerealScience,15(1),15-27.LinktoArticleReadAbstractAnimprovedenzymicmethodforthedeterminationofstarchdamageinwheatflourhasbeendevelopedandcharacterized.Theproposedmethodissimpleandreliable,andenablesupto20samplestobemeasuredinduplicatein2h.Asingleassaytakesapproximately40min.Theassayprotocolisintwophases.Inthefirst,thefloursampleisincubatedwithpurifiedfungalalpha-amylasetoliberatedamagedstarchgranulesassolubleoligosaccharides.Aftercentrifugation,theoligosaccharidesinthesupernatantarehydrolysedbyamyloglucosidasetoglucoseinphase2.Theglucoseisthenquantifiedwithaglucoseoxidase/peroxidasereagent.Theproposedmethodthereforeavoidspotentialerrorsassociatedwithexistingstandardassays,whichemployunpurifiedamylasepreparationsandnon-specificreducinggroupmethodstoquantifythehydrolyticproducts.Despitetheuseofpurifiedassaycomponents,theproposedstarchdamagemethoddidnotexhibitanabsoluteend-pointtotheactionofalpha-amylaseinphase1.Thiswasduetoalowrateofhydrolysisofundamagedgranules,andisafeatureofenzymicmethodsforstarchdamagedetermination.Otheramylolyticenzymes,includingbeta-amylase,isoamylaseandpullulanase,andcombinationsoftheseenzymes,wereevaluatedasalternativestoalpha-amylaseintheproposedmethod.Theseenzymes,whenusedalone,gavenobenefitsovertheuseofalpha-amylase.Whenusedincombinationwithalpha-amylase,therewasasynergisticactiononundamagedgranules.Atestkitbasedontheassayformatdescribedinthispaperisthesubjectofaninternationalinterlaboratoryevaluation.Collaborativeevaluationofanenzymaticstarchdamageassaykitandcomparisonwithothermethods.Gibson,T.S.,Kaldor,C.J.&McCleary,B.V.(1993).CerealChem.,70(1),47-51.LinktoArticleReadAbstractAcommerciallyavailableenzymaticassaykitforthemeasurementofstarchdamageinwheatflourwascomparedwithcurrentstandardmethods,andthekit"sprecisionandrepeatABIlityweredeterminedinacollaborativestudy.Starchdamagevaluesdeterminedonarangeofflourswiththeassaykitcorrelatedwell(r>0.96)withthosedeterminedbyexistingstandardenzymaticmethods.Theprecisionofthekitwasevaluatedinacomprehensiveinterlaboratorystudy.Thekitprocedurewasfoundtobehighlyrepeatable(relativestandarddeviation,2.94-6.80%)andreproducIBLe(relativestandarddeviation,5.00-10.30%).Measurementoftotalstarchincerealproductsbyamyloglucosidase-alpha-amylasemethod:collaborativestudy.McCleary,B.V.,Gibson,T.S.&Mugford,D.C.(1997).JournalofAOACInternational,80,571-579.LinktoArticleReadAbstractAnAmericanAssociationofCerealChemists/AOACcollaborativestudywasconductedtoevaluatetheaccuracyandreliabilityofanenzymeassaykitprocedureformeasurementoftotalstarchinarangeofcerealgrainsandproducts.Thefloursampleisincubatedat95degreesCwithThermostablealpha-amylasetocatalyzethehydrolysisofstarchtomaltodextrins,thepHoftheslurryisadjusted,andtheslurryistreatedwithahighlypurifiedamyloglucosidasetoquantitativelyhydrolyzethedextrinstoglucose.Glucoseismeasuredwithglucoseoxidase-peroxidasereagent.Thirty-twocollaboratorsweresent16homogeneoustestsamplesas8blindduplicates.Thesesamplesincludedchickenfeedpellets,whitebread,greenpeas,high-amylosemaizestarch,whitewheatflour,wheatstarch,oatbran,andspaghetti.Allsampleswereanalyzedbythestandardprocedureasdetailedabove;4samples(high-amylosemaizestarchandwheatstarch)werealsoanalyzedbyamethodthatrequiresthesamplestobecookedfirstindimethylsulfoxide(DMSO).Relativestandarddeviationsforrepeatability(RSD(r))rangedfrom2.1to3.9%,andrelativestandarddeviationsforreproducibility(RSD(R))rangedfrom2.9to5.7%.TheRSD(R)valueforhighamylosemaizestarchanalyzedbythestandard(non-DMSO)procedurewas5.7%;thevaluewasreducedto2.9%whentheDMSOprocedurewasused,andthedeterminedstarchvaluesincreasedfrom86.9to97.2%.Measurementofcarbohydratesingrain,feedandfood.McCleary,B.V.,Charnock,S.J.,Rossiter,P.C.,O’Shea,M.F.,Power,A.M.&Lloyd,R.M.(2006).JournaloftheScienceofFoodandAgriculture,86(11),1648-1661.LinktoArticleReadAbstractProceduresforthemeasurementofstarch,starchdamage(gelatinisedstarch),resistantstarchandtheamylose/amylopectincontentofstarch,β-glucan,fructan,glucomannanandgalactosyl-sucroseoligosaccharides(raffinose,stachyoseandverbascose)inplantmaterial,animalfeedsandfoodsaredescribed.Mostofthesemethodshavebeensuccessfullysubjectedtointerlaboratoryevaluation.AllmethodsarebasedontheuseofenzymeseitherpurifiedbyconventionalchromatographyorproducedusingmolecularBIOLOGytechniques.Suchmethodsallowspecific,accurateandreliablequantificationofaparticularcomponent.Problemsincalculatingtheactualweightofgalactosyl-sucroseoligosaccharidesintestsamplesarediscussedindetail.Starchproperties,invitrodigestibilityandsensoryevaluationoffresheggpastaproducedfromoat,teffandwheatflour.Hager,A.S.,Czerny,M.,Bez,J.,Zannini,E.&Arendt,E.K.(2013).JournalofCerealScience,58(1),156-163.LinktoArticleReadAbstractSpecificdietaryrequirements,e.g.ceoliacdisease,aswellasincreasedconsumerdemandforproductsofhighnutritionalvalue,makestheproductionofpastafromalternativecerealsinteresting.Rawmaterialcharacterisationshowedthattheutilisationofoatandteffflourisbeneficialastheseingredientscontainhigherlevelsoffibreandmineralcompositionissuperiortothatofwheat.Starchpropertiessignificantlyinfluencepastaqualityandthereforedamagedstarchlevels,amylaseactivity,pastingpropertiesandgelatinisationtemperaturesoftheflourswereinvestigated.Fresheggpastabasedonwheat,oatandteffflourwasproduced.Sensorypropertiesofoatspaghettiwerefoundtobeveryclosetothatofwheatpastabutimprovementofsmoothnessandaromaisnecessary,whileteffspaghettishowedreducedsensoryquality.Aninvitroenzymaticdigestionwasperformedusingadialysissystemtomimicthebehaviourofpastaaseatenandmakepredictionsontheglycemicindex(GI).ThepredictedGIwashighestforwheatpasta,followedbyteffandoat.Ultrastructurewasstudiedusingconfocallaserscanningmicroscopy,allowingthevisualisationofdifferencesinstarchgranulesizeandshapeaswellasgelatinisationoccurringduringthecookingprocess.Effectofsorghumflourcompositionandparticlesizeonqualitypropertiesofgluten-freebread.Trappey,E.F.,Khouryieh,H.,Aramouni,F.&Herald,T.(2014).FoodScienceandTechnologyInternational,1082013214523632.LinktoArticleReadAbstractWhite,food-gradesorghumwasmilledtoflourofvaryingextractionrates(60%,80%,and100%)andpin-milledatdifferentspeeds(nopin-milling,low-speed,andhigh-speed)tocreatefloursofbothvariablecompositionandparticlesize.Flourswerecharacterizedforflourcomposition,totalstarchcontent,particlesizedistribution,color,damagedstarch,andwaterabsorption.Breadwascharacterizedforspecificvolume,crumbstructureproperties,andcrumbfirmness.Significantdifferenceswerefound(PP Nutritionalpropertiesandultra-structureofcommercialglutenfreefloursfromdifferentbotanicalsourcescomparedtowheatflours.Hager,A.S.,Wolter,A.,Jacob,F.,Zannini,E.&Arendt,E.K.(2012).JournalofCerealScience,56(2),239-247.LinktoArticleReadAbstractCoeliacpatientssufferfromanimmunemediateddisease,triggeredbytheingestionofaproteincomposite(gluten)foundinwheat,ryeandbarley.Consequently,thereisaneedforproductssuchasbreadorpasta,madefromalternativecerealgrainsorpseudocereals.Afairproportionoftheglutenfreeproductscurrentlyonthemarketarenutritionallyinadequate.Hence,itwastheaimofthisstudytoinvestigatethenutrientcompositionofsevencommonlyusedcommercialglutenfreeflours(oat,rice,sorghum,maize,teff,buckwheatandquinoa)andcomparethemtowheatandwholemealwheatflour.Inadditiontothelevelsofallmajorcompounds,alsomineralcomposition,fattyacidprofile,phytate,polyphenolsandfolatecontentweredetermined.Furthermore,propertiesofcarbohydrateswerestudiedingreaterdetail,lookingattotalanddamagedstarchlevels;total,solubleandinsolubledietaryfibrecontentaswellasamylose/amylopectinratio.Proteinswerefurtherinvestigatedbymeansofcapillaryelectrophoreses.Additionally,theultra-structureofthesematerialswasexploredusingscanningelectronmicroscopy.Theresultsshowthatmaizeandriceflourarepoorregardingtheirnutritionalvalue(lowprotein,fibre,folatecontents).Incontrast,teffaswellasthepseudocerealsquinoaandbuckwheatshowafavourablefattyacidcompositionandarehighinproteinandfolate.Inparticular,quinoaandteffarecharacterisedbyhighfibrecontentandarehighincalcium,magnesiumandiron.Thereforethesefloursrepresentnutrientdenserawmaterialsfortheproductionofglutenfreefoods.Qualityvariationsinfloursusedforpretzelmanufacturing.Yao,N.&Seetharaman,K.(2010).InternationalJournalofFoodScience&Technology,45(10),2052-2061.LinktoArticleReadAbstractResearchontheflourpropertiesandtheirinfluenceonpretzelcharacteristicsisscarce.Inthefirstpartofthestudy,flourproteinquantityandquality,flourpastingpropertiesandsolventretentionpropertiesof108floursampleswereinvestigatedtohelpprofiletheflourpropertiesusedbythepretzelindustry.Fourdifferentflourswithawiderproteinrangethanwhatwasrevealedintheflourevaluationwereselectedtoproducepretzelsandtodeterminetherelationshipbetweenflourpropertiesandthefinalproductquality.Pretzelhardness,colourandpastingpropertieswereusedasameasureofpretzelquality.Resultsindicatedthathardwheatflourwouldproduceaharderpretzelbutwouldnotaffectthesurfacecolouroffinalproduct.However,softwheatflourwithalowerdamagedstarch,lowwaterabsorptionlevelsandlowerwaterbindingpowersduringoperationsisdesiredformakinghardpretzel.Effectofcornpreparationmethodsondry-grindethanolproductionbygranularstarchhydrolysisandpartitioningofspentbeersolids.Lamsal,B.P.,Wang,H.&Johnson,L.A.(2011).BioresourceTechnology,102(12),6680-6686.LinktoArticleReadAbstractTwocornpreparationmethods,rollermillflakingandhammermillgrinding,werecomparedforefficientprocessingofcornintoethanolbygranularstarchhydrolysisandsimultaneousfermentationbyyeastSaccharomycescerevisiae.Cornwaseithergroundinahammermillwithdifferentsizescreensorcrushedinasmooth-surfacedrollermillatdifferentrollergapsettings.Thepartitioningofbeersolidsandsizedistributionofsolidsinthethinstillagewerecompared.Themeanparticlediameterd50forpreparationsvariedwithset-upsandrangedbetween210and340µmforgroundcorn,and1180–1267µmforflakedcorn.Theethanolconcentrationsinbeerweresimilar(18–19%v/v)forgroundandflakedpreparations,however,ethanolproductivityincreasedwithreducedparticlesize.Rollerversushammermillingofcornreducedsolidsinthinstillageby28%,anddoubledthevolumepercentoffines(d507µm)inthinstillageanddecreasedcoarse(d50122µm)byhalfcomparedtohammermilling.Flakingasacornpreparationtechniquefordry-grindethanolproductionusingrawstarchhydrolysis.Lamsal,B.P.&Johnson,L.A.(2012).JournalofCerealScience,56(2),253-259.LinktoArticleReadAbstractA23full-factorialstudywasdesignedtostudytheeffectofcornpreparationmethods(flakingandgrinding)ondry-grindethanolperformanceusingrawstarchhydrolysis(RSH)process.Moisturecontent(15,22%),flakerrollergapsetting(0.508mm,1.016mm),andgrindingwerestudied.Fifteenhundredgofcornsampleswerecracked,rollerpressed,andwereeithergroundfurtherorretained,alongwithcontrolgroundcorn.Abimodalsizedistributionwasobservedforgroundcorn,regardlessofflaking.Moistureat22%resultedinbigger-sizedflakeswithd50between~1.3and1.8mm,comparedto~138–169µmforgroundcorn.Notallgroundcornresultedinhigherethanolconcentrationinfermentationbeer;theethanollevelsinbeerdidnotreflectthestarchhydrolysistrendthatfavoredgroundcorn.Inarelatedstudy,thebeerethanolconcentrationdidnotshowacleartrendwithrollermillgapsettingwhilefermentingtheflakesproducedat0.203,0.305,0.406,and0.508mmgapsettings.Generally,flakesfromcornat22%moistureresultedinhigherethanolcontentinbeer.Rollermillflakingwasfoundcomparabletohammermillgrindingfordry-grindcornethanolviarawstarchhydrolysisandyeastfermentation.Chemicalcompositionandfunctionalpropertiesofnativechestnutstarch(CastaneasativaMill).Cruz,B.R.,Abraão,A.S.,Lemos,A.M.&Nunes,F.M.(2013).CarbohydratePolymers,94(1),594-602.LinktoArticleReadAbstractStarchisolationmethodscanchangetheirphysico-chemicalandfunctionalcharacteristicshinderingtheestablishmentofastarch-foodfunctionalityrelation.Asimplehighyieldandsoftisolationmethodwasappliedforchestnut(CastaneasativaMill)starchconsistinginsteepingandfruitdisintegrationina25mMsodiumbisulfitesolutionandpurificationbysedimentation.Starchintegrity,physico-chemicalcomposition,morphologyandfunctionalpropertiesweredetermined,beingobservedsignificantdifferencesfrompreviousdescribedmethodsforchestnutstarchisolation.TheX-raypatternwasofB-type,withadegreeofcrystallinityrangingfrom51%to9%,dependentonthestarchmoisturecontent.Theonset,peak,andconclusiongelatinizationtemperatureswere57.1°C,61.9°Cand67.9°C,respectively.Totalamylosecontentwas26.6%,andtherewasnotfoundanyevidenceforlipidcomplexedamylose.Swellingpowerat90°Cwas19g/gstarch,andtheamountofleachedamylosewas78%ofthetotalamylosecontent.NativechestnutstarchpresentsatypeBpastingprofilesimilartocornstarchbutwithalowergelatinization(56.1°C)andpeakviscosity(79.5°C)temperatures,makingnativechestnutstarchapotentialtechnologicalalternativetocornstarch,especiallyinapplicationwherelowerprocessingtemperaturesareneeded.Changesinricewithvariabletemperatureparboiling:thermalandspectroscopicassessment.Himmelsbach,D.S.,Manful,J.T.&Coker,R.D.(2008).Cerealchemistry,85(3),384-390.LinktoArticleReadAbstractRapidviscoanalysis(RVA)anddifferentialscannningcalorimetry(DSC)providedoverallassessmentsoftheeffectsofvariabletemperaturesoakingat30,50,70,and90°Candsteamingat4,8,and12min.Calculationoftherelativeparboilingindex(RPI)andpercentgelatinizationprovidedgoodmetricsfordeterminingtheoveralleffectsofpartialparboiling.FT-Ramanandsolid-state13CCP-MASNMRspectroscopiesprovidedinsighttoconformationalchangesinproteinandstarchofpaddyriceundervariousparboilingconditions.RVAshowedlowerpastingcurvesandDSCshowedlowerΔHwithincreasedtemperatureandsteamingtimes.Alargedecreaseinviscosityoccurredwithonlythe30-4treatmentasopposedtorawrice.ThisobservationwasconsistentwithFT-Ramanresultsthatindicatedsubstantialconversionoftheproteinfromα-helixtootherconformations.DSCindicatedincompletegelatinizationofstarch,evenwith90°Csoakingand12minofsteaming.Solid-state13CCP-MASNMRspectroscopyconfirmedthisresult.However,itindicatedthepercentofVh/amorphousplustheremainingcrystallinestarchinthe90-12treatmentwasequaltotheamorphousandpartially-orderedstarchincommerciallyparboiledrice.Theseresultssuggestthatpartialparboiling,90°Csoaking,andmorethan8minofsteaming(ideally≈12min)ofpaddyriceissufficienttoinducechangesthatinactivateenzymesandprovideenoughstarchgelatinizationtopreventkernelbreakage.Determinationofformulationandprocessingfactorsaffectingslowlydigestiblestarch,proteindigestibilityandantioxidantcapacityofextrudedsorghum–maizecompositeflour.Licata,R.,Chu,J.,Wang,S.,Coorey,R.,James,A.,Zhao,Y.&Johnson,S.(2014).InternationalJournalofFoodScience&Technology,49(5),1408-1419.LinktoArticleReadAbstractHigh-temperaturehigh-pressureextrusionofsorghum–maizecompositeflour,ofpotentialforhealthyfoodmanufacture,wasinvestigatedbyfactorialexperimentaldesigntodeterminetheeffectoflevelofsorghumindrymix(15–60%);finalbarrelzonetemperature(120–150°C);totalmoistureinbarrel(21.4–25.8%);totalinputrate(2.3–6.8kgh-1);andscrewspeed(250–450rpm)onextrudateslowlydigestiblestarch(SDS),phenoliccontent,antioxidantcapacity,proteindigestibility,densityandexpansionratio.ExtrudateSDSincreasedwithincreasingsorghumlevelanddecreasedasthebarreltemperatureincreased.Totalphenoliccontentandantioxidantcapacitywerepositivelyassociatedwithsorghumlevel.Proteindigestibilitywasassociatednegativelywithsorghumlevelandpositivelywithbarreltemperature.Extrudatedensitywasassociatedpositivelywithtotalmoistureandnegativelywithbarreltemperatureandinputrate.Sorghumindrymix,finalbarrelzonetemperatureandtotalmoistureinbarrelwerethethreemostsignificantindependentvariablesinfluencingextrudatedependantvariables.Analysisofstarchamylolysisusingplotsforfirst-orderkinetics.Butterworth,P.J.,Warren,F.J.,Grassby,T.,Patel,H.&Ellis,P.R.(2012).CarbohydratePolymers,87(3),2189-2197.LinktoArticleReadAbstractInvestigatorsoftenstudyproductreleasefromstarchesduringprolongedincubationswithα-amylaseinvitro.Thereactiontimecoursesusuallyfittoalinearformofafirstorderrateequation,i.e.,ln[(C∞−Ct)/C∞]=−kt.ThisequationcallsforanaccurateestimateofC∞,i.e.,theconcentrationofproductattheendofthereaction.EstimatesofC∞fromdigestibilitycurvescanbeunreliable.TheGuggenheimmethoddoesnotrequirepriorknowledgeofC∞butseemsnottohavebeenappliedtostarchhydrolysisdata.Analternativemethodisalsoavailableinwhichthelogarithmoftheslope(LOS)ofadigestibilitycurveatvarioustimepointsisplottedagainsttime.ThisallowsestimationsofbothkandC∞andcanalsorevealwhetherchangesoccurindigestionratefromrapidtoslowasdigestionproceeds.WedescribetheGuggenheimandLOSmethodsandprovideexamplesoftheirapplicationtostarchdigestibilitydata.ValidationofMethodsAACCMethod76-31.01ICCStandardNo.164RACIStandardMethodColourimetricmethodforthedeterminationofStarchDamageincerealfloursPrinciple:                             (fungalα-amylase)(1)Damaged(orgelatinised)starch+H2O→maltodextrins               (amyloglucosidase)(2)Maltodextrins+H2O→D-glucose                 (glucoseoxidase)(3)D-Glucose+H2O+O2→D-gluconate+H2O2                                          (peroxidase)(4)2H2O2+p-hydroxybenzoicacid+4-aminoantipyrine→                                    quinoneimine+4H2OKitsize:                         200assaysMethod:                         Spectrophotometricat510nmTotalassaytime:             ~40minDetectionlimit:                0.5-100%ofsampleweightApplicationexamples:CerealfloursandothermaterialsMethodrecognition:   AACC(Method76-31.01),ICC(StandardNo.164)andRACI(StandardMethod)AdvantagesVerycosteffective Allreagentsstablefor>2yearsafterpreparation Onlyenzymatickitavailable Veryspecific Simpleformat Mega-Calc™softwaretoolisavailablefromourwebsiteforhassle-freerawdataprocessing Standardincluded

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