پديد آورنده :
نصري نصرآباد، مسيح
عنوان :
بررسي فرآيند خشك كردن ورقه هاي قارچ به شيوه تلفيقي الكتروهيدروديناميك و انجمادي با پيش تيمار فراصوت
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
مكانيك ماشين هاي كشاورزي
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي
صفحه شمار :
پانزده، 125ص.: مصور، جدول، نمودار
استاد راهنما :
علي اسحق بيگي
استاد مشاور :
مرتضي صادقي، علي نصيرپور
توصيفگر ها :
مصرف انرژي , خصوصيات كيفي محصول خشك شده , قارچ دكمه اي , سينتيك خشك كردن
تاريخ نمايه سازي :
1394/06/25
استاد داور :
عباس همت، ناصر همدمي
تاريخ ورود اطلاعات :
1396/10/04
چكيده فارسي :
به فارسي و انگليسي
چكيده انگليسي :
026Combined Electrohydrodynamic and Freeze Drying Process of Mushroom Slices Pretreated by Applying Power Ultrasound Masih Nasri Masih nasri@ag iut ac ir Jun 1 2015 Department of Biosystems Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiAli Esehaghbeygi esehaghbeygi@cc iut ac irAbstractTo prevent damage corruption and maintain the quality of fruits vegetables and food their long term protectionis essential There are several methods for preserving foods including canning freezing and drying Amongthese methods drying is an effective and practical method for reducing post harvest food losses especially fordeveloping countries that have poor facilities for low temperature processes In this study freeze dryingcombined with electrohydrodynamic drying EHD is examined as an improved method for drying mushroomslices At first the pre experiments were conducted in order to find three optimum intensities The effects of threelevels of intensity3 04 3 8 and 4 56 kV cm 15 2 11 4 and 9 12 kV at 5 3 and 2 cm respectively on dryingtime water effective diffusion coefficient energy consumption and quality characteristics of dried mushroomslices with EHD and electrohydrodynamic combined vaccum freeze drying EHFD systems were investigatedand compared with vaccum freeze drying VFD ANOVA showed that there were significant differencesbetween EHD EHFD and VFD treatments for all of the studied responses Results indicated that EHFD had lessdrying time more the effective moisture diffusion coefficient average drying rate and energy consumption thanEHD treatments with the same intensity EHFD has less energy consumption than vacuum freeze dryingtherefore as a strategy to reduce energy consumption in industrial drying is recommended In the second part ofthis study effect of electric field intensity on qualitative properties rehydration percentage of surfacereduction shrinkage and color difference of dried mushroom slices with EHD and EHFD systems were studied Results showed an increment in rehydration of EHFD compared to EHD were due to the vacuum freeze drying EHFD had significant differences compared to EHD treatments with same intensity for b and E responses ofdried mushrooms slices for both EHFD and EHD treatments E response decrease with reducing the intensityof the electric field The result showed for EHD and EHFD as drying time was lower the percentage of surfacereduction was more There was no significant difference between the shrinkage percentage of EHD and EHFDtreatments In the third part of this study the effect of electric field intensity was investigated on the amount offree water present in dried mushroom and on specific heat curve obtained from diffrential scaning calorimetry inthe range of 20 to 50 C in EHD and EHFD and were compared with VFD Cooling thermograms indicatedabsence of freezable water for samples were dried with EHFD and EHD approaches and thus maintaining driedmushroom slices with both ways can be done satisfactory EHFD 11 4 kV and 3 cm gap 3 8 kV cm waschosen as the optimum treatment Then to evaluate effect of ultrasound pretreatment power at 40 KHz and 3minutes was applied before the optimum treatment and was not more favorable Keywords Electrohydrodynamic EHD Vaccum freeze drying VFD Drying kinetics Energy consumption
استاد راهنما :
علي اسحق بيگي
استاد مشاور :
مرتضي صادقي، علي نصيرپور
استاد داور :
عباس همت، ناصر همدمي
