The objectives of this research were to study the effect of hot air velocity on the changes of the moisture content and temperature of preserved tomatoes undergoing combined conveyor system and hot air drying. Specific energy consumption, physical properties in term of color and shrinkage, and sensory evaluation of dried preserved tomatoes were also investigated. The preserved cherry tomatoes were dried at a drying temperature of 80oC, and hot air velocity of 2 and 4 m/s until the moisture contents of the preserved tomatoes were lower than 18% wet basis. The experimental results showed that the hot air velocity had effect on the changes of the moisture content and temperature of preserved tomatoes. Specific energy consumption, total color difference, shrinkage percentage, and sensory evaluation results of dried preserved tomatoes of the hot air velocity of 2 and 4 m/s were not significantly different (P>0.05). Moreover, the dried preserved tomatoes obtained from this research had significantly lower sensory scores in term of color and appearance than those obtained from the local market (P£0.05). However, sensory scores in term of flavor, texture and overall preference of the dried preserved tomatoes obtained from this research and the local market were not significantly different (P>0.05).
Keywords
Conveyor System, Drying, Hot Air, Preserved Tomatoes