تاثير شرايط مختلف خشك كردن بر ويژگي هاي موز خشك شده در هواي داغ

Influence of Different Drying Conditions on Dried Banana Properties by Hot Air

Banana slices were prepared in three thickness 3,5,10 mm with three pretreatment Tl, chemical treatment in 1% sodium metabisuphite,T2 blanching in boiling water then with 1% sodium metabisulphite solution and T3,blanching with boiling water and then with 1% solution mixture of 1:1 citric-ascorbic acid. The pretreated samples were dried to final moisture content in convective air drier at 60,70,80 °c .Some quality factors such as sugar content, ascorbic acid, color and rehydration ratio along with drying time and rate were evaluated. The results showed that pretreatments increased drying rate and decreased drying time as drying time in blanched treatments showed 40% reduction. Thickness increased drying time and temperature decreased it and increased drying rate just as anticipation. Ascorbic acid and sugar content most preserved in higher temperature but had negative effects on color and rehydration ratio.