保鲜与加工StorageandProcess2023,23(0):00-00加工研究不同频率下超声波水处理对苹果内传热传质影响规律的试验研究朱宗升,单晓芳,陈爱强,周静,白浩志,刘斌(天津商业大学机械工程学院,天津市制冷技术重点实验室,天津300134)摘要:为探究超声波处理对果蔬加工过程中热质传递的影响规律,以苹果为研究对象,结合不同频率(40、68、80kHz)超声波处理技术,分别进行超声波辅助低温水浴试验和超声波水预冷处理辅助苹果片真空冷冻干燥试验。结果表明:超声波辅助低温水浴可有效强化苹果与冷水间的热量交换,频率为80kHz时,苹果果肉中部和近果核处的冷却系数与对照组相比分别增加了35.3%和28.6%;超声波水预冷处理后,真空冷冻干燥过程有效水分扩散系数比对照组分别增加了51.6%(超声波频率40kHz)、55.9%(超声波频率68kHz)、58.7%(超声波频率80kHz)。关键词:超声波水处理;苹果;预冷;真空冷冻干燥;热流密度;扩散系数ExperimentalStudyontheEffectsofUltrasonicWaterTreatmentsonHeatandMassTransferinApplesunderDifferentFrequenciesZHUZong-sheng,SHANXiao-fang,CHENAi-qiang,ZHOUJing,BAIHao-zhi,LIUBin(SchoolofMechanicalEngineering,TianjinUniversityofCommerce,KeyLaboratoryofRefrigerationTechnologyofTianjin,Tianjin300134,China)Abstract:Inordertoexploretheinfluenceofultrasonictreatmentsonheatandmasstransferduringfruitsandvegeta⁃blesprocessing,applesweretakenastheresearchobject,andultrasonicassistedlowtemperaturewaterbathtestandultrasonicwaterprecoolingassistedvacuumfreezedryingtestsofapplesliceswererespectivelycarriedoutcombinedwithultrasonictreatmenttechnologyofdifferentfrequencies(40,68,80kHz).Theresultsshowedthatultrasonicassist⁃edlowtemperaturewaterbathcouldeffectivelystrengthentheheatexchangebetweenapplesandcoldwater.Whenthefrequencywas80kHz,thecoolingcoefficientsinthemiddleandnearthecoreofapplepulpwereincreasedby35.3%and28.6%,respectively,comparedwiththecontrolgroup.Afterultrasonicwaterprecoolingtreatment,theeffectivewa⁃terdiffusioncoefficientsinvacuumfreeze-dryingprocesswereincreasedby51.6%(ultrasonicfrequencyof40kHz),55.9%(ultrasonicfrequencyof68kHz)and58.7%(ultrasonicfrequencyof80kHz),respectively,comparedwiththeco...