Drying of apple slice by halogen dryer

In this study، drying of Golab apple slice by Digital Halogen Dryer was investigated. The experiments were carried out at two levels of apple thickness (3 and 6 mm)، three levels drying temperature (80، 100 and 120 ºC) and two kinds of drying profile (Fast and Standard). Lose of moisture content، drying time and brittleness were measured and taste of dried apple slices were evaluated by a test panel. The results of experiments showed that the maximum lose of moisture content related to the thickness of 6 mm and standard drying profile. In both profile drying، the maximum lose of moisture content related to the thickness of 6 mm and drying temperature of 120 ºC. The maximum lose of moisture content for 3 mm thickness occurred at 80 and 100 ºC. There were significant differences in both of drying profiles and thickness of 6 mm at different temperatures and lose of moisture content. In fast drying profile، there was no significant difference between lose of moisture content and different thicknesses for all levels of temperature. But in standard profile and temperature of 100 ºC، the maximum lose of moisture content was in thickness of 6 mm. The slices which were dried at 80 and 100 ºC had good taste but it had mediocre tastes for slices which were dried at 120 ºC. Increasing drying temperature caused to increase brittleness of apple slices. Finally، the optimum condition of drying was found at standard drying profile، drying temperature of 100 ºC and slice thickness of 6 mm because of more lose of moisture content، acceptable brittleness and better taste.