Document Type : Full Research Paper


1 Technical and Vocational University Beheshti of Urmia.

2 Department of agricultural mechanization Engineering, University of Tabriz.


Introduction: Thin layer drying of agricultural products using an infrared dryer (IR) is one of the interesting and low cost methods of dehydration. Quality of dried products could be increased if the engineering aspects and proper selection of performance parameters be well considered in the designing of a dryer. The dryer that uses two or more drying methods in combination, produces in the most cases the higher quality product with lower energy consumption. 
Materials and methods: In this study, an available IR dryer was modified and a combined IR and hot- air dryer was constructed. According to the reported quality factors in the literatures and market desire, the developed dryer performance was evaluated during the drying of banana slices. The studied factors were the effects of the thickness of slices (4 and 6 mm) and the surface temperature of the product (55, 65 and 75 °C) on the drying kinetic and quality of the dried product.  Some various mathematical models were fitted to the experimental data and results and among them the best fitted model was selected.
Results & discussion: Based on the results, the different surface temperature and thickness of the slices had a significant effect on the drying time and color changes of the samples. However, they did not affect the density of samples. Drying time of the banana slices (to reach the moisture ratio of 0.04) with the thickness of 4 mm was 155, 105 and 80 min at the surface temperatures of 55, 65 and 75 °C, respectively. At the thickness of 6 mm, the drying time was 230, 130 and 100 min, respectively at the mentioned temperature. The minimum color change were observed at the thickness of 4 mm (ΔE=32.41) and surface temperature of 55°C (ΔE= 28.99). The samples dried at the temperature of 55 °C had the best quality. Evaluation of the various mathematical models indicated that the Page model is the most suitable to predict the drying kinetic of banana slices under the studied condition. Comparing the obtained results with the reported ones for just hot-air or IR drying of banana slices; it is obvious that in point of product quality and drying time, the combined IR and hot- air dryer has better conditions


امیرنجات، ح.، ۱۳۸۹، ارزیابی اثرات توأم روش‌های جابه‌جایی حرارت و تابش اشعه مادون‌قرمز بر خشک‌کردن لایه نازک قارچ خوراکی، پایان ‌نامه کارشناسی ارشد. دانشگاه تربیت مدرس.
موسوی بایگی، ف.، فرهمند، ع.، تقی‌زاده، م. و ضیا فروغی،1.، 1395، مدل سازی خشک‌کردن لایه نازک خرمالو به دو روش هوای داغ و مادون‌قرمز، فصلنامه علوم و صنایع غذایی، دوره 13، شماره 53، 161-171.
بداقی، ا.، ۱۳۹۲، طراحی و ساخت خشک‌کن آزمایشگاهی ترکیبی مادون‌قرمز هوای گرم، پایان‌ نامه کارشناسی ارشد، دانشگاه تبریز.
زیرجانی، ل. و توکلی پور،ح.، 1389، مطالعه امکان تولید برگه موز توسط روش خشک‌کردن ترکیبی هوای گرم و ماکروویو، نشریه پژوهش‌های علوم و صنایع غذایی ایران. جلد 6۶، شماره ۱، 73-86.
حسینی‌قابوس، س.، سیدین‌اردبیلی، م.، کاشانی‌نژاد، م.، اسدی، غ. و اعلمی، م.، 1395، سینتیک انتقال جرم خشک‌کردن ترکیبی مادون‌قرمز- هوای داغ کدو حلوایی، علوم غذایی و تغذیه، دوره13، شماره 4، 5-16.
قربانی، ر.، دهقان‌نیا، ج.، سیدلو هریس، س. و قنبرزاده، ق.، ۱۳۹۲، مدل سازی دانسیته ظاهری در طی خشک کردن آلوی پیش تیمار شده با اولتراسوند وآبگیری اسمزی. فصلنامه علوم و فناوری‌های نوین غذایی، دوره 1، شماره ٢، 23-38.
کریمی، ف.، ۱۳۹۰، مدل‌سازی سینتیک خشک‌‌کردن ورقه‌های موز، پایان نامه کارشناسی ارشد، گروه علوم و صنایع غذایی. دانشکده کشاورزی، دانشگاه تبریز.
AOAC, 1990, Official Method of Analysis, Association of Official Analytical Chemists (No.934.06).
Baini, R., & Langrish, T. A. G., 2009, Assessment of colour development in dried bananas measurements and implications for modelling. Journal of Food Engineering, 93,177-182.
Cakmak, G. & Yildiz, C., 2011, the drying kinetics of seeded grape in solar dryer with PCM-based solar integrated collector. Food and Bioproducts Processing, 89, 103-108.
Doymaz, I. & Pala, M., 2002, the effect of dipping pretreatment on air-drying rates of the seedless grapes. Journal of Food Engineering, 52: 413-417.
Doymaz, I., 2007, the kinetics of forced convective air-drying of pumpkin slices. Journal of Food Engineering, 79, 243–248.
Fernandez, F. A.N., Linhares J.F.E. & Rodrigues, S., 2008, Ultrasound as pre-treatment for drying of pineapple. Ultrasonics Son chemistry, 15, 1049-1054.
Hakan, O.M. & Can, E., 2006, Mathematical modeling of thin layer drying of Golden apples. Journal of Food Engineering, 77, 119–125.
Hebbar, U.H., Vishwanatham, K.H. & Ramesh, M.N., 2004, combined infrared and hot air dryer for vegetables. Journal of Food Engineering, 65, 557-563.
Khampakool, A., Soisungwan, S., & Sung S.H, 2019. Potential application of infrared assisted freeze drying (IRAFD) for banana snacks: Drying kinetics, energy consumption, and texture. LWT - Food Science and Technology, 99, 355–363.
Koc, B., Eren, I. & Ertekin, F. K., 2008, Modelling bulk density, porosity and shrinkage of quince during drying: The effect of drying method. Journal of Food Engineering, 85, 340-349.
Ortuno, C., Perez-Munuera, I., Puig, A. & Riera, E., 2010, Influence of power ultrasound application on mass transport microstructure of orange peel during hot air drying. Journal of Food Engineering, 3, 153-159.
Pan, Z. & Atungulu, G. G., 2011, Infrared heating for food and agricultural processing. Taylor & Francis Group, 5, 353-360.
Pekke, M.A., Pan, Z., Atungulu, G.G., Gary Smith, G., & Thompson, J.F., 2013, Drying characteristics and quality of bananas under infrared radiation heating. International Journal of Agricultural and Biology Engineering, 6 (3), 58-70.
Sharma, G. P., Verma, R. C. & Pathare, P. B., 2005, Thin-layer infrared radiation drying of onion slice. Journal of Food Engineering, 67, 361-366.
Swasdisevi, T., Devahastin, S., Sa-Adchom, P. & Soponronnarit, S., 2009. Mathematical modeling of combined far-infrared and vacuum drying banana slice. Journal of Food Engineering, 92, 100–106.
Talla, A., Puiggali, J.-R., Jomaa, W. & Jannot, Y., 2004, Shrinkage and density evolution during drying of tropical fruits: application to banana. Journal of Food Engineering, 64, 103-109.
Thuwapanichayanan, R., Prachayawarakorn, S., Jaruwan Kunwisawa, J., & Soponronnarit, S., 2011, Determination of effective moisture diffusivity and assessment of quality attributes of banana slices during drying. LWT - Food Science and Technology, 44, 1502-1510.
Yaldiz, O., Ertekin, C. & Uzun, H. I., 2001, Mathematical modeling of thin layer drying of sultana grapes. Energy, 26, 457-465.
Yan, Z., Sousa-Gallagher, M.J. & Oliveira, F.A.R., 2008, Shrinkage and porosity of banana, pineapple and mango slices during air-drying. Journal of Food Engineering, 84, 430–4.