پديد آورنده :
خاكباز حشمتي ، مريم
عنوان :
خشك كردن لايه نازك پسته در دو نوع خشك كن ﴿آفتابي فعال و قفسه اي﴾
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
علوم و صنايع غذايي
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي
صفحه شمار :
چهارده ،105،[II]ص:مصور ،جدول ،نمودار
يادداشت :
ص.ع به: فارسي وانگليسي
استاد راهنما :
ناصر همدمي
استاد مشاور :
شهرام دخاني ، مرتضي صادقي
توصيفگر ها :
مدلسازي سينتيك
تاريخ نمايه سازي :
18/1/87
استاد داور :
محمد شاهدي ،امين الله معصومي
چكيده فارسي :
به فارسي و انگليسي : قابل رويت در نسخه ديجيتال
چكيده انگليسي :
AbstractThe pistachio nut Pistachia vera is one of the favourite tree nuts of the world and iswidely cultivated in saline dry and hot areas like Iran proper harvest and goodprocessing are the major basis of having good quality Drying of agricultural products hasalways been of great importance for the preservation of food by human beings Sundrying and cabinet drying are well known food preservation techniques that reduce themoisture contents of agricultural product and thereby prevents deterioration within aperiod of time regarded as the safe storage period Since all fresh pistachios can not beconsumed at the time of harvest preservation provides a larger market allowingconsumers to buy the preserved pistachio around the year Pistachio nuts may be driedusing either solar energy or mechanical systems Traditional sun drying is a slow processcompared with other drying methods but it is said to give dried pistachios theirdistinctive quality Simulation models are helpful in designing new or in improvingexisting drying systems or for the control of the drying operation A forced convectionsolar dryer and a cabinet dryer were used in this research Pistachio nuts were dried in thecabinet dryer with different temerature and air velocities 45 50 55 and 60 C and 0 5 1and 1 5 m s solar dryer and open sun drying Effective water diffusivity values rangedfrom 9 7 10 10 to 4 58 10 10 m2 s The results showed that drying time in the solardryer is shorter than open sun drying Shrinkage and rehydration ability of food materialsduring air drying adversely affects the quality of the dried products The experimentalshrinkage data show a linear behavior with moisture content with a reduction in samplevolume with decreasing moisture content The effect of temperature and air velocity onthe shrinkage phenomenon can be neglected The experimental data didn t show thedominating effect of temperature and air velocity on the rehydration ability of thisproduct The influence of temperature and air velocity on the rehydration ability can thusbe neglected The drying data as the moisture ratio MR versus drying time were fitted tothe 13 thin layer drying models The comparison criteria used to evaluate goodness of fit namely the coefficient of determination R2 the root mean square error RMSE and thereduced chi square 2 The Page model for cabinet dryer the Page model for sun dryerand the two term exponential model for open sun drying gave higher R2 and lower RMSEand 2 values than other models Finally a numerical model was developed to simulatethe moisture transfer during thin layer drying of pistachio nuts by finite difference methodon MATLAB software The predicted water loss content was validated by comparisonwith the experimental values R2 0 99 It can be concluded that this model describeswell the mechanism of moisture diffusion in a one directional transfer during thin layerdrying of pistachio nuts
استاد راهنما :
ناصر همدمي
استاد مشاور :
شهرام دخاني ، مرتضي صادقي
استاد داور :
محمد شاهدي ،امين الله معصومي
