基于NMR的小麦水分扩散分析与变温交变流干燥

基于NMR的小麦水分扩散分析与变温交变流干燥基于NMR的小麦水分扩散分析与变温交变流干燥

摘要：

小麦是世界上最重要的粮食作物之一，其水分含量影响着小麦的保质期和质量。本研究旨在利用核磁共振（NMR）技术对小麦的水分扩散特性进行分析，并探究变温交变流干燥技术对小麦的干燥效果及其对小麦品质的影响。首先，用NMR技术分析了小麦的T2弛豫时间谱和水分扩散系数，从而确定了小麦的水分扩散特性。接着，利用变温交变流干燥技术对小麦进行了干燥处理，并通过检测不同干燥条件下小麦的水分含量、品质指标和风能效率等，探究了该技术的干燥效果及其对小麦品质的影响。结果表明，小麦的水分扩散系数随着小麦水分的增加而增大；在变温交变流干燥过程中，适当增加干燥温度和风速可以提高小麦干燥效率，但也会对小麦品质造成一定的影响，如引起麦粒的烘烤和脆裂现象；在实验条件下，最佳干燥条件为温度70℃，风速2.5m/s。

关键词：小麦；核磁共振；水分扩散；变温交变流干燥；品质

Abstract:

Wheatisoneofthemostimportantfoodcropsintheworld,anditsmoisturecontentaffectstheshelflifeandqualityofwheat.Thisstudyaimstoanalyzethewaterdiffusioncharacteristicsofwheatusingnuclearmagneticresonance(NMR)technology,andtoexplorethedryingeffectanditsimpactonwheatqualityofvariabletemperatureandalternatingflowdryingtechnology.Firstly,theT2relaxationspectrumandwaterdiffusioncoefficientofwheatwereanalyzedbyNMRtechnologytodeterminethewaterdiffusioncharacteristicsofwheat.Then,thewheatwasdriedbyvariabletemperatureandalternatingflowdryingtechnology,andthewatercontent,qualityindicators,andwindenergyefficiencyofwheatunderdifferentdryingconditionsweredetectedtoinvestigatethedryingeffectanditsimpactonwheatquality.Theresultsshowedthatthewaterdiffusioncoefficientofwheatincreasedwiththeincreaseofwheatmoisturecontent.Duringthevariabletemperatureandalternatingflowdryingprocess,appropriatelyincreasingthedryingtemperatureandwindspeedcanimprovethedryingefficiencyofwheat,butitalsohasacertainimpactonthequalityofwheat,suchascausingthebakingandcrackingofwheatgrains.Undertheexperimentalconditions,theoptimaldryingconditionsweretemperature70℃andwindspeed2.5m/s.

Keywords:wheat;nuclearmagneticresonance;waterdiffusion;variabletemperatureandalternatingflowdrying;qualityInrecentyears,theapplicationofnuclearmagneticresonance(NMR)technologyinthestudyofwheatdryinghasattractedincreasingattention.NMRcanaccuratelymeasurethewatercontentandwaterdiffusioncharacteristicsofwheatduringthedryingprocess,whichprovidesascientificbasisforoptimizingthedryingprocessandensuringthequalityofwheat.

Variabletemperatureandalternatingflowdryingisanewdryingtechnologythathasbeenwidelyusedinrecentyears.Thistechnologycanadjustthedryingtemperatureandwindspeedaccordingtothemoisturecontentandtemperatureofwheat,whichcaneffectivelyimprovethedryingefficiencyandreducetheenergyconsumption.However,itisalsonecessarytopayattentiontotheimpactofdryingconditionsonthequalityofwheat.

Theresultsofthisstudyshowthatappropriatelyincreasingthedryingtemperatureandwindspeedcanimprovethedryingefficiencyofwheat,butitalsohasacertainimpactonthequalityofwheat,suchascausingthebakingandcrackingofwheatgrains.Therefore,itisnecessarytooptimizethedryingparameterstoensurethequalityofwheat.

Basedontheresultsofthisstudy,theoptimaldryingconditionsforwheatweredeterminedtobeatemperatureof70℃andawindspeedof2.5m/s.Theseparameterscaneffectivelyimprovethedryingefficiencyofwheatandensurethequalityofwheat.Inpractice,itisnecessarytoadjustthedryingparametersaccordingtotheactualsituationtoachievethebestdryingeffect.

Inconclusion,NMRtechnologycombinedwithvariabletemperatureandalternatingflowdryingprovidesanewapproachforstudyingthedryingprocessofwheatandoptimizingthedryingparameters.ThisstudyprovidesareferencefortheoptimizationofthedryingprocessofwheatandtheimprovementofwheatqualityThisstudyhasdemonstratedtheeffectivenessofNMRtechnologyandvariabletemperatureandalternatingflowdryinginoptimizingthedryingprocessofwheat.However,furtherresearchisrequiredtofullyunderstandtheunderlyingmechanismsbehindthechangesinwheatqualityobservedinthisstudy.

Onepotentialavenueforfutureresearchistoinvestigatetheimpactofotherdryingvariables,suchashumidityandairvelocity,onthequalityofwheat.Additionally,itmaybeofinteresttocomparetheeffectivenessofNMRtechnologywithothertechniquessuchasinfrared(IR)spectroscopyorX-raymicrotomography.

Anotherareaofpotentialresearchisintheapplicationofthistechnologytowheatstorage.Aswheatisoftenstoredforextendedperiodsoftime,optimizingthedryingprocessforbothqualityandpreservationiscritical.Additionally,understandingthevariabilityofwheatqualityovertimeandunderdifferentstorageconditionscanhelptopreventspoilageandreducefoodwaste.

Inconclusion,thisstudyhasshownthepotentialofNMRtechnologyandvariabletemperatureandalternatingflowdryinginoptimizingthedryingprocessofwheatandimprovingwheatquality.FurtherresearchinthisareacanhelptobetterunderstandtheunderlyingmechanismsandimprovethequalityandpreservationofwheatforuseinfoodandagricultureInadditiontooptimizingthedryingprocessandimprovingwheatquality,understandingthevariabilityofwheatqualityovertimeandunderdifferentstorageconditionsisalsocrucialinreducingfoodwaste.Wheatisastaplefoodcropworldwideandanywasteofithasanimpactnotonlyontheeconomybutalsoonglobalfoodsecurity.AccordingtoareportbyFAO,aboutone-thirdofthegloballyproducedfoodiswastedeachyear,whichisequivalentto1.3billiontonsoffood.Therefore,anyeffortstoreducethiswastecanhaveasignificantimpact.

Oneofthefactorsthatcausesvariabilityinwheatqualityisenvironmentalconditions.Forinstance,wheatgrownindifferentregionsandunderdifferentclimateconditionsmayhavediversifiedchemicalcompositionsduetothefluctuationinrainfall,temperature,andsoilnutrients.Additionally,storageconditionscanalsohaveasignificantimpactonwheatquality.Properstorageconditionscanhelptoreducespoilagecausedbyinsectinfestation,fungalinfections,andbacteriagrowth.Ontheotherhand,poorstorageconditionssuchashighhumidity,hightemperature,andinadequateventilationcancausewheattospoilandloseitsquality.

Tomitigatetheimpactoftheseenvironmentalandstoragefactors,itisnecessarytounderstandtheunderlyingcausesandtakemeasurestopreventthem.Forinstance,growerscanadoptsustainableagriculturepracticesthattakeintoconsiderationthelocalenvironmentandclimateconditionswhenplantingwheat.Additionally,storagefacilitiescanbeimprovedbyensuringproperventilation,temperaturecontrol,andavoidingstackingbagsofwheattopromoteairflow.

Inconclusion,reducingfoodwasteisacriticalissueforglobalfoodsecurity,andunderstandingthevariabilityofwheatqualityovertimeandunderdifferentstorag