Document Type : Research Paper

Authors

1 Ph.D. Student, Department of Food Science and Technology, Tabriz Branch, Islamic Azad University, Tabriz, Iran

2 Islamic Azad University Tabriz Branch · Department of Agriculture.

3 Associate Prof. Dr., Department of Food Science and Technology, Tabriz Branch, Islamic Azad University, Tabriz, Iran.

Abstract

In the present study, the two-dimensional modelling of heat transfer during the deep-fat frying process was investigated. In the first stage, three temperature levels of 150, 160, and 170 °C were selected for frying and recorded by a K-type thermocouple. In order to record the temperature changes of the sample during the frying process, a three-channel T-thermocouple was placed in the center, on the surface, and between these two points of the sample. In the next step, based on the temperature-to-time diagram, during five periods of frying, the moisture and oil content were measured at all three oil temperatures. As the temperature of the oil increased, both the oil and moisture content of the potatoes decreased. Then, the heat transfer parameter, including the convective heat transfer coefficient, in the range of 83.97578.4 W/m2.K, was calculated and determined. The result showed that the convective heat transfer coefficient is high at high temperatures because of moisture exiting and the high turbulence of the oil flow. This coefficient also has a large influence on frying. The convective heat transfer coefficient was considered the most important parameter in heat transfer modeling, and it was used in software simulation. The geometry of the potato slices was disc-shaped. The mathematical equations of heat transfer were solved using Fourier's law, and the results of solving the equations in modelling were used by COMSOL Multi-Physics software version 5.3.1, and the temperature distribution at the surface and inside the sample was modelled with this software. Finally, the available profiles were represented.

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Main Subjects

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