基于NMR的小麥水分擴散分析與變溫交變流干燥

基于NMR的小麥水分擴散分析與變溫交變流干燥基于NMR的小麥水分擴散分析與變溫交變流干燥

摘要：

小麥是世界上最重要的糧食作物之一，其水分含量影響著小麥的保質期和質量。本研究旨在利用核磁共振（NMR）技術對小麥的水分擴散特性進行分析，并探究變溫交變流干燥技術對小麥的干燥效果及其對小麥品質的影響。首先，用NMR技術分析了小麥的T2弛豫時間譜和水分擴散系數(shù)，從而確定了小麥的水分擴散特性。接著，利用變溫交變流干燥技術對小麥進行了干燥處理，并通過檢測不同干燥條件下小麥的水分含量、品質指標和風能效率等，探究了該技術的干燥效果及其對小麥品質的影響。結果表明，小麥的水分擴散系數(shù)隨著小麥水分的增加而增大；在變溫交變流干燥過程中，適當增加干燥溫度和風速可以提高小麥干燥效率，但也會對小麥品質造成一定的影響，如引起麥粒的烘烤和脆裂現(xiàn)象；在實驗條件下，最佳干燥條件為溫度70℃，風速2.5m/s。

關鍵詞：小麥；核磁共振；水分擴散；變溫交變流干燥；品質

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