Ohmic Heating of Aloe vera Gel: Electrical Conductivity and Energy Efficiency

Document Type : Research Article

Authors

1 Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, I.R. IRAN

2 Department of Food Additives, Food Science and Technology Research Institute-ACECR, Mashhad, I.R. IRAN

3 Department of Mechanic Biosystem, Faculty of Agriculture, Tarbiat Modares University, Tehran, I.R. IRAN

Abstract

Ohmic heating is defined as a process which alternating electric current is passed through food with the primary purpose of heating it due to the electrical resistance and can be specially applied as an alternative heating method. In this research, Aloe vera gel concentrates having 0.5-2% soluble solids were ohmically heated up to 60°C by using four different voltage gradients (30–60 V/cm). The dependence of electrical conductivity on temperature, voltage gradient, and concentration were obtained. Results indicated that there was a linear relationship between temperature and electrical conductivity. The range of the electrical conductivity was 0.45 to1.20 S/m, which was dependent on the concentration and voltage gradient, although the effect of concentration was very higher than voltage gradient. The ohmic heating System Performance Coefficients (SPCs) were calculated by using the energies given to the system and taken by the Aloe vera gel samples and were in the range of 0.67- 0.89 and the highest SPC (0.89) was observed at 0.5 % and 30 V/cm.

Keywords

Main Subjects

References

[1] Miranda M., Maureira H., Rodriguez K. & Vega-Gálvez A., Influence of Temperature on the Drying Kinetics, Physicochemical Properties, and Antioxidant Capacity of Aloe Vera (Aloe Barbadensis Miller) Gel, Journal of Food Engineering, 91: 297-304 (2009).
[2] Reynolds T., “Aloes: the Genus Aloe”, CRC Press, (2004).
[3] Olariu, R. Aloe Vera–Natures Silent Healer, Hygiene. Public Health 59:79-88 (2009).
[4] Ahmed J., Ramaswamy H.S., Kasapis S., Boye J.I. “Novel Food Processing: Effects on Rheological and Functional Properties”, CRC Press, (2009).
[5] Johnson B.S., “Ohmic Heating as an Alternative Food Processing Thechnology”, Thesis of Master of Science. Kansas State University (2003).
[6] De Alwis A., Fryer P., Operability of the Ohmic Heating Process: Electrical Conductivity Effects, Journal of Food Engineering 15:21-48 (1992).
[7] Zoltai P., Swearingen P., “Product Development Considerations for Ohmic Processing”, Food Technology (USA) (1996).
[8] Assiry A., Gaily M., Alsamee M. & Sarifudin A., Electrical Conductivity of Seawater During Ohmic Heating, Desalination, 260: 9-17 (2010).
[9] Icier F., Ilicali C., Electrical Conductivity of Apple and Sourcherry Juice Concentrates During Ohmic Heating, Journal of Food Process Engineering, 27: 159-180 (2004).
[10] Icier F., Ilicali C., Temperature Dependent Electrical Conductivities of Fruit Purees During Ohmic Heating, Food Research International, 38: 1135-1142 (2005).
[11] AOAC. “Official Methods of Analysis, Association of Official Analytical Chemist: Arlington”, VA. (no. 934.06). (1990).
[12] Saberian H., Hamidi Esfahani Z., Abbasi S., Effect of Conventional and Ohmic Pasteurization on Some Bioactive Components of Aloe vera Gel Juice, Iran J Chem Chem Eng. (IJCCE), 34(3): 99-108 (2015).
[13] Wang W.-C., Sastry S.K., Salt Diffusion Into Vegetable Tissue as a Pretreatment for Ohmic Heating: Determination of Parameters and Mathematical Model Verification, Journal of Food Engineering, 20: 311-323 (1993).
[14] Castro I., Teixeira J., Salengke S., Sastry S., Vicente A., Ohmic Heating of Strawberry Products: Electrical Conductivity Measurements and Ascorbic Acid Degradation Kinetics, Innovative Food Science & Emerging Technologies, 5: 27-36 (2004).
[15] Saberian H., Amooi M., Hamidi-Esfahani Z., Modeling of Vacuum Drying of Loquat Fruit, Nutrition & Food Science, 44: 24-31 (2014).
[16] Castro I., Teixeira J., Salengke S., Sastry S., Vicente A., The Influence of Field Strength, Sugar and Solid Content on Electrical Conductivity of Strawberry Products, Journal of Food Process Engineering, 26:17-29 (2003).
[17] Rizvi S., “Thermodynamic Properties of Food in Dehydration”, Dalam MA Rao and Rizvi, SSH (eds). Engineering Properties of Foods. In): Marcel Dekker, New York (1995).
[18] Icier F., “The Experimental Investigation and Mathematical Modelling of Ohmic Heating of Foods”, Ph.D. Diss., Ege University, The Institute of Natural and Applied Sciences: Izmir, Turkey (2003).
[19] Kim K.-T, Choi H.-D., Kim S.-S., Hong H.-D., Changes in Heating Profiles of Apple Juice by Ohmic Heating, Journal of the Korean Society for Applied Biological Chemistry, 41: 431-436 (1998).
 [20] Darvishi H., Khostaghaza M.H., Najafi G., Ohmic Heating of Pomegranate Juice: Electrical Conductivity and pH Change, Journal of the Saudi Society of Agricultural Sciences, 12:101-108 (2013).
[21] Zell M., Lyng J., Morgan D., Cronin D., Minimising Heat Losses During Batch Ohmic Heating of Solid Food, Food and Bioproducts Processing, 89: 128-134 (2011).
[22] Mercali G.D., Schwartz S., Marczak L.D.F., Tessaro I.C., Sastry S., Ascorbic Acid Degradation and Color Changes in Acerola Pulp During Ohmic Heating: Effect of Electric Field Frequency, Journal of Food Engineering, 123:1-7 (2014).
[23] Qihua T., Jindal V., Van Winden J., Design and Performance Evaluation of an Ohmic Heating unit for Liquid Foods, Computers and Electronics in Agriculture, 9: 243-253 (1993).
[24] Palaniappan S., Sastry S.K., Electrical Conductivities of Selected Solid Foods During Ohmic Heating, Journal of Food Process Engineering, 14(3): 221-236 (1991a).
[25] Darvishi H., Hosainpour A., Nargesi F., Khoshtaghaza M.H., Torang H., Ohmic Processing: Temperature Dependent Electrical Conductivities of Lemon Juice, Modern Applied Science 5: 209- (2011).
[26] Icier F., Ilicali C., Temperature Dependent Electrical Conductivities of Fruit Purees During Ohmic Heating, Food Research International, 38: 1135-1142 (2005).
[27] Palaniappan S., Sastry S.K., Electrical Conductivity of Selected Juices: Influences of Temperature, Solids Content, Applied Voltage, and Particle Size, Journal of Food Process Engineering, 14:247–260 (1991b).
[28] Assiry A., Sastry S.K., Samaranayake C., Degradation Kinetics of Ascorbic Acid During Ohmic Heating with Stainless Steel Electrodes, Journal of Applied Electrochemistry, 33: 87-196 (2003).
[29] Zhao Y., Kolbe E., Flugstad B., A Method to Characterize Electrode Corrosion During Ohmic Heating, Journal of Food Process Engineering, 22: 81-89 (1999).
[30] Samaranayake C.P., “Electrochemical Reactions During Ohmic Heating”, The Ohio State University (2003).
[31] Saberian H., Hamidi-Esfahani Z., Gavlighi HA., Barzegar M., Optimization of Pectin Extraction from Orange Juice Waste Assisted by Ohmic Heating, Chemical Engineering and Processing: Process Intensification, 117:154-161 (2017).
[32] Darvshi H., Hosainpour A., Nargesi F., Fadavi A., Exergy and Energy Analyses of Liquid Food in an Ohmic Heating Process: A Case Study of Tomato Production, Innovative Food Science & Emerging Technologies, 31: 73-82 (2015).
Iranian Journal of Chemistry and Chemical Engineering
Volume 37, Issue 5 - Serial Number 91
September and October 2018
Pages 157-165

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