Reihaneh Golestani - Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez Ave., P.O.Box ۱۵۸۷۵-۴۴۱۳, Tehran, Iran
Abdolreza Aroujalian - Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez Ave., P.O.Box ۱۵۸۷۵-۴۴۱۳, Tehran, Iran
Ahmadreza Raisi - Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez Ave., P.O.Box ۱۵۸۷۵-۴۴۱۳, Tehran, Iran
Mohammad Amani - Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez Ave., P.O.Box ۱۵۸۷۵-۴۴۱۳, Tehran, Iran

Drying is one of the widely used techniques of vegetables and fruits preservation. The aim of this work was to determine the effect of drying temperature and modified atmosphere on the dehydration time and color of convection dried apples. For this purpose, apples dried under air and inert environmental (nitrogen) condition at temperature in the range from 60 to 80˚C. The colors of samples are investigated by a computer vision system that composes of a digital color camera for recording image in a digital format and a computer for storage the images. The sample color in RGB system converts into L*a*b* unit using a matlab program. Color analysis showed that dried samples at 60˚C have the less browning and total color differences. The dehydration ratio decreased with an increase in the drying temperature

Apple; convection drying; color change; computer vision image analysis; modified atmosphere