Determination of Some Vegetable Drying Characteristics in Convectional and Fluidized Bed Drying Systems (Turkish with English Abstract)

Abstract

Drying characteristics of spinach, swiss chard and leek were determined both in convectional and fluidized bed dryers at 70 oC and experimental moisture data were fitted into thin layer drying models. Percentage of weight loss of spinach, swiss chard and leek samples were 49.30, 40.85 ve 23.97% in convectional drying whereas 81.50, 80.90 ve 81.70% in fluidized bed drying, respectively. Initial water activity of spinach, swiss chard and leek samples were 0.99, 0.97 and 0.96 while final water activities were 0.93, 0.93 and 0.91 for convectional drying and 0.30, 0.27 and 0.48 for fluidized bed drying at the end of drying period. Fluidized bed drying was found to be more efficient than convectional drying. Wang-Singh model for convectional drying and logarithmic model for fluidized bed drying provided a good fit for the experimental data (R2>0.999). Water activity and percentage of weight loss values were in good agreement.

Keywords

• Vegetable, convectional drying, fluidized bed drying, model.  

Konveksiyonel ve Akışkan Yataklı Sistemlerde Bazı Sebzelerin Kuruma Karakteristiklerinin Belirlenmesi

Abstract

Bu çalışmada konveksiyonel ve akışkan yataklı kurutma sistemleri kullanılarak ıspanak, pazı ve pırasanın 70 oC'deki kuruma karakteristikleri belirlenmiş ve deneysel veriler 6 farklı ince tabaka kurutma modeline uyarlanmıştır. Kuruma periyodu sonunda ıspanak, pazı ve pırasanın konveksiyonel kurutucudaki % ağırlık (su) kayıpları sırasıyla % 49.30, 40.85 ve 23.97 iken akışkan yataklı kurutucuda ise % 81.50, 80.90 ve 81.70 olmuştur. Ispanak, pazı ve pırasada 0.99, 0.97 ve 0.96 olan başlangıç su aktivitesi değerleri konveksiyonel kurutma sonunda 0.93, 0.93 ve 0.91 ve akışkan yataklı kurutma sonunda 0.30, 0.27 ve 0.48 olmuştur. Akışkan yataklı kurutma sistemi konveksiyonel sisteme göre daha efektif bir kuruma sağlamıştır. Kurutma karakteristikleri konveksiyonel kurutmada en iyi Wang-Singh modeli ve akışkan yataklı kurutmada logaritmik model ile ifade edilmiştir (R2>0.999). Örneklerin su aktivitesi değerleri ve ağırlık kaybı ilişkisi uyum içindedir.

Keywords

• Sebze, konveksiyonel kurutma, akışkan yataklı kurutma, model.  

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