EVALUATION OF POTATO SLICES DRYING USING SOLAR DRYER

Document Type : Original Article

Author

Associate Prof. of Agric. Eng., Fac. of Agric., Zagazig Univ., Egypt.

Abstract

The objective of the present study was to investigate the drying characteristic curves and the drying duration when drying potato slices using natural convection solar dryer. For that sake an experimental setup was developed. Measurements of total solar radiation on the plane of the collector, ambient air temperature, drying air temperature and moisture loss in weight were collected. A group of experiments were conducted using potato slices with thickness of 1 mm to study the effect of pretreatments on drying characteristics. The maximum temperature attained in the drying chamber is 52 oc  at 13:00 and 14:00 pm and the maximum temperature attained in the collector is 75oc  at 14:00 pm while the corresponding values of solar radiation and ambient temperature were 876.5 W/m2and 38oc, respectively. The final moisture contents were 7.15 and 4.48 db in B(blanch + calcium chloride) and C (blanch + citric acid) treatments, while in A (blanch), D (blanch + potassium meta sulphate)   and E (blanch + acitric acid) were 14.20, 22.35 and 13.73 db. Consequently, citric acid solution and calcium chloride solution were more effective solutions in potato slices drying. The slices treated with citric acid (C), potassium meta sulphite (D) and acetic acid (E) provided better color for drying compared with the slices that treated with blanch only (A) and with calcium chloride (B) under which the colors were brown. The effective moisture diffusivities of pretreated with treatments (A, B, C, D and E) were (1.35×10-11, 1.39×10-11, 1.45×10-11 , 1.23×10-11and 1.40×10-11m2/s), respectively. Based on these results, pretreated samples with citric acid solution (C) had the highest effective moisture diffusivity compared with other samples.

Keywords


Adedeji, A.A., T.K.Gachovska, , M.O. Ngadidi, and G.S.V. Raghavan, (2008). Effect of pretreatments on drying characteristics of okra. Dry. Technol. 26, 1251–1256.
Aghbashlo, M., M.H. Kianmehr, and A.Arabhosseini, (2009).Modeling of thin-layer drying of potato slices in length of  continuous band dryer. Energy Converse. Manage. 50, 1348 –1355.
Akpinar, E., A.Midilli, and Y. Bicer, (2003). Single layer drying behaviour of potato slices in a convective cyclone dryer and mathematical modelling. Energy Convers.Manage. 44,1689–1705.
AL-Khuseibi, M.K., S.S.  Sabablani, and C.O. Perera, (2005). Comparison of water blanching and high hydrostatic pressure  effects on drying kinetics and quality of potato. Dry. Technol. 23, 2449–2461.
Arumuganathan, T., M.R.Manikantan, R.D. Rai, S. Anandakumar, and V.Khare, (2009).Mathematical modeling of drying kinetics of milkymushroom in a fluidized bed dryer. Int.Agrophysics 23, 1–7.
Bingol, G., Z.Pan, , J.S. Roberts, Y.O.  Devres, and M.O.  Balaban, (2008). Mathematical modeling of microwave-assisted convective heating and drying of grapes. Int. J.Agric. Biol. Eng. 1(2), 46–54.
Claussen, I.C., T.Andresen, T.M.  Eikevik, and I.Strommen, (2007). Atmospheric freeze drying –modeling and simulation of a tunnel dryer. Dry. Technol. 25, 1959–1965.
Cunningham, S.E., W.A.M. Mcminn, T.R.A.  Magee, and P.S. Richardson, (2008). Experimental study of rehydration kinetics of potato cylinders. Food Bioprod. Process. 86, 15–24.
Crank, J. (1975). The Mathematics of Diffusion, Clarendon Press, Oxford,U.K..
Duan, X., M.Zhang, X. Li, and A.S.  Mujumdar, (2008). Microwave freeze drying of sea cucumber coated with nano scale silver. Dry. Technol. 26, 413–419.
Falade, K.O., T.O. Olurin, E.A.  Ike, and O.C. Aworh, (2007).Effect of pretreatment and temperature on air-drying of Dioscorea alata and Dioscorea rotundata slices. J. Food Eng. 80,1002–1010.
Falade, K.O. and O.J.  Solademi, (2010).Modeling of air drying of fresh and blanched sweet potato slices. Int. J. Food Sci. Technol. 45, 278–288.
FAO (2011). Statistical database. http://faostat.fao.org/site/ 567/desktop default. Aspx ? Page ID=567#ancor.
Hassini, L., S.Azzouz, R. Peczalski, and A.Belghith, (2007). Estimation of potato moisture diffusivity from convective drying kinetics with correction for shrinkage. J. Food Eng. 79, 47–56.
Hatamipour, M.S., H.H.Kazemi, A.Nooralivand, and A. Nozarpoor, 2007. Drying characteristics of six varieties of sweet potatoes in different dryers. Food Bioprod. Process.85(C3), 171–177.
Kaya, A., O. Aydin, and C. Demirtas, (2009). Experimental and theoretical analysis of drying carrots. Desalination 237,285–295.
Kim, S.J., H.S.Chung, , B.Y. Lee, S.D.  Kim, and K.S.Youn, (2004). Quality improvement of dried jujubes through selected pre-treatments. Food Sci. Biotechnol. 13, 406–410.
Kingsly, R.P., R.K.Goyal, M.R.  Manikantan, and S.M.  Ilyas, (2007). Effects of pretreatments and drying air temperature on drying behaviour of peach slice. Int. J. Food Sci. Technol. 42,65–69.
Lee, J.H. and H.J. Kim, (2009).Vacuum drying kinetics of Asian white radish (Raphanus sativus L.) slices. LWT – Food Sci. Technol. 42, 180–188.
Madamba, P.S. (2003). Thin layer drying models for osmotically pre-dried young coconut. Dry. Technol. 21,1759–1780.
Miranda, M.L. and J.M. AguILilera, (2006). Structure and texture properties of fried potato cubes. Food Rev. Int. 22, 173–201.
Muthukumaran,A., C.Ratti, and G.S.V.  Raghavan, (2008). Foam-mat freeze drying of egg white – mathematical part II: Freeze drying and modelling. Dry. Technol. 26,513–518.
Okos, M.R., G.Narsimhan, R.K.  Singh, and A.C. Witnauer, (1992). Food dehydration. In Handbook of Food Engineering (D.R. Heldman and D.B. Lund, eds.) pp. 437–544,Marcel Dekker,New York, NY.
Pardshi, I.L., S.Arora, and P.A. Borker, (2009). Thin-layer drying of green peas and selection of a suitable thin-layer drying model. Dry. Technol. 27, 288–295.
Rossello, C., J.Canellas, , S.Simal, and A.Berna, (1992). Simple mathematical model to predict the drying rates of potatoes. J.Agric. Food Chem. 40, 2374–2378.
Sacilik, K., R.Keskin, and A.K. Elicin, (2006).Mathematical modeling of solar tunnel drying of thin layer organic tomato. J. Food Eng. 73, 231–238.
Saravacos, G.D., S.N. Marousis, and G.S. Raouzeos, (1988). Effect of ethyloleate on the rate of air-drying of foods. J. Food Eng. 7, 263–270.
Severini, C., A.Baiano, T.Depilli, , B.F. Carbone and A.Derossi, (2005). Combined treatments of blanching and dehydration: Study on potato cubes. J. Food Eng. 68,289–296.
Shishehgarha, F., J.Makhlouf, and C.Ratti, (2002). Freeze-drying characteristics of strawberries. Dry. Technol. 20, 131–145.
Tarhan, S., G.Ergunes, and O.F. Taser, (2006). Selection of chemical and thermal pretreatment combination to reduce the dheydration time of sour cherry. J. Food Process Eng. 29, 651–663.
Teles, U.M., A.N.Fernandes, S. Rodrigues, A.S. Lima, G.A.  Maia, and R.W. Figueiredo, (2006). Optimization of osmotic dehydration of melons followed by air-drying. Int. J. Food Sci. Technol. 41, 674–680.
Zogzas, N.P., Z.B. Maroulis, and D.Marinos-Kouris, (1996).Moisture diffusivity data compilation in food stuffs. Dry. Technol. 14, 2225–2253.