الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The main experiments were carried out through the year of 2020 in a small workshop in Cairo Governorate to assess the utilization of infrared radiation for drying and sterilizing tomato slices using an infrared dryer. To fulfill the objective of this research work, some operating parameters affecting the performance of the infrared dryer were taken into consideration: Three different levels of infrared intensity (0.973, 1.093, and 1.161 kW/m2), three different inlet air temperatures (40, 50 and 60°C) and three different tomato slices thicknesses (3, 5 and 7mm). Two different drying models, simple exponential model (Lewis’s 1921) and the modified exponential model (Henderson and Pabis’s 1961) were used for describing the drying behavior and predicting the changes in moisture content of tomato slices during the drying process. Evaluation of the infrared dryer was carried out taking into consideration tomato slices moisture ratio and final dried tomato slices quality in terms of ascorbic acid, total phenolic content, lycopene pigment and antioxidant activity. The obtained data reveal that the final dried tomato slices quality were in the optimum region with the use of the infrared dryer under the following conditions: - 0.973 kW/m2 radiation intensity, - 50 0C air temperature, - 5 mm tomato slices thickness. The findings also illustrated that both investigated models could describe the drying behavior of tomato slices satisfactory.