Document Type : Original Article


1 Msc. Student, Department of Mechanics of Agricultural Machinery and Mechanization, Faculty of Agriculture, Shahid Chamran University, Ahvaz, Iran

2 Associate Professor, Department of Mechanics of Agricultural Machinery and Mechanization, Faculty of Agriculture, Shahid Chamran University, Ahvaz, Iran

3 Assistant Professor, Department of Mechanics of Agricultural Machinery and Mechanization, Faculty of Agriculture, Shahid Chamran University, Ahvaz, Iran


Objective: The main objective pursued in this paper is to investigate the energy consumption for drying of potato slices using vacuum-infrared drying method. Methods: Drying of potato slices with the thicknesses of 1, 2 and 3 mm were conducted at vacuum levels of zero (without vacuum), 20, 80 and 140 mm [Hg], infrared radiation at power levels of 100, 150 and 200 W in the three repetition. Results: The results show that with the slice thickness decreases, acts of vacuum and increasing lamp power, energy consumption be reduced. Maximum of energy consumption occurred in a vacuum of 140 mm Hg, but in general it can be stated that by applying vacuum, energy consumption is reduced due to the shortening of the drying time. Data analysis showed that use of vacuum in conjunction with infrared radiation drying increased energy consumption in comparison to merely infrared drying. In the combined vacuum-infrared process, drying time and consequently energy consumption decreased in comparison to the merely infrared drying. The maximum thermal utilization efficiency (31.01%) and minimum energy requirements (5.3 kWh/kg H2O) was calculated for drying of potato slices computed at infrared power of 150 W without vacuum at thickness of 1 mm. The minimum thermal utilization efficiency (2.13%) and maximum energy requirements (185.14 kWh/kg H2O) for drying of potato slices was achieved at infrared radiation power of 100 W with vacuum level of 80 mm [Hg] at thickness of 2 mm.


AOAC. (1990). Official Methods of Analysis. No. 934-06. Association of Official Chemists, Washington, DC. Bakal, S.B., Sharma, P.G., Sonawan, S.P. and Verma, R.C. (2011). Kinetics of potato drying using fluidized bed
dryer. Journal of Food Science and technology. 19: 127- 135.
Doymaz, I. (2004). Convective air drying characteristics of thin layer carrots. Journal of Food Engineering, 61:359-364.
Ehiem, J.C., Irtwange, S.V. and Obetta, S.E. (2009). Design and Development of an Industrial Fruit and Vegetable Dryer. Research Journal of Applied Sciences, Engineering and Technology, 1(2): 44-53.
FAO. (1981). Food loss prevention in perishable crop. Food and Agriculture Organization of the United Nations.
Garayo, J. and Moreira, R. (2002). Vacuum frying of potato chips. Journal of Food Engineering, 55: 181-191.
Gogus, F. (1994). The effect of movement of solutes on milliard reaction during drying. Ph.D. Thesis, Leeds University, Leeds, UK.
Hatamipour, M.S., Kazemi, H.H., Nooralivand, A. and
Nozarpoor, A. (2007). Drying characteristic s of six varieties of sweet potatoes in different dryers. Food Bioprod Process, 85(C3): 171-177.
Hayes, G.D. (1987). Food Engineering Data Handbook. England: Longman Scientific and Technical.
Kemp, I.C. (2012). Fundamentals of Energy Analysis of Dryers. Modern Drying Technology. Volume 4: Energy Savings, First Edition, pp 1-46.
Kocabiyik, H. and Tezer, D. (2009). Drying of carrot slices using infrared radiation. Int J Food Sci Technol, 44: 953ñ959.
Kowalski, S. J., and Mierzwa, D. (2011). Hybrid drying of red bell pepper: energy and quality issues. Drying Technology, 29: 1195 ñ1203.
Mongpraneet, S., Abe, T. and Tsurusaki, T. (2002). Accelerated drying of welsh onion by far infrared radiation under vacuum conditions. Journal of
Food Engineering, 55: 147-156.
Mongpraneet, S., Abe, T. and Tsurusaki, T. (2004). Far infrared- vacuum and convection drying of welsh onion. Transactions of the ASAE, 45: 1529-2535.
Moreira, R. G. (2001). Impingement drying of food using hot air and superheated steam. Journal of Food Engineering, 49: 291ñ295.
Motevali, A., Minaei, S., Khoshtaghaza, M.H., and Amirnejat, H. (2011a). Comparison of energy consumption and Specific Energy Requirements of
Different methods for drying mushroom slices. Energy, 36: 6433-6441.
Motevali, A., Minaei, S. and Khoshtagaza, M.H. (2011b). Evaluation of energy consumption in different drying methods. Energy Conversion and
Management, 52(2): 1192ñ1199.
Mujundar, A. S. (1987). Handbook of Industrial Drying, Marcel Dekker Inc., New York, NY. Nazghelichi, T., Kianmehr, M. H., and Aghbashlo,
M. (2010). Thermodynamic analysis of fluidized bed drying of carrot cubes. Energy, 35(12): 4679ñ4684.
Nimmol, C. (2010). Vacuum Far-infrared Drying of Foods and Agricultural Materials. The Journal of KMUTNB. Japan, 20(1): 37-44. Pedreschi, F., Moyano, P., Kaack, K. and Granby, K. (2005). Color changes and acrylamide formation in fried potato slices. Food Research International,38: 1ñ9.
Ratti, C. and Mujumdar, A.S. (1995). Infrared drying, in: A.S. Mujumdar, (eds.), Handbook of industrial drying: Volume 1, Marcel Dekker,NewYork.
Sharma, G.P., Verma, R.C., Pathare, P.B., (2005). Thinlayer infrared radiation drying of onion slices. Journal of Food Engineering, 67:361-366.
Soysal, A. (2004). Microwave Drying Characteristics of Parsley. Biosystems Engineering, 89(2): 167ñ173.
Swasdisevi, T., Devahastin, S., Sa-Adchom, P. and Soponronnarit. S. (2009). Mathematical modeling of combined far-infrared and vacuum drying banana slice. Journal of Food Engineering, 92: 100-106.
Umesh Hebbar, H., Vishwanathan, K.H., and Ramesh, M.N. 2004. Development of combined infrared and hot air dryer for vegetables. J. Food Eng, 65(4): 557ñ563.
Yongsawatdigul, J. and Gunasekaran, S. (1996). Microwave-vacuum drying of cranberries. Part II: Quality evaluation. Journal of Food Process Engineering,
20(12): 145ñ156.