Effective Moisture Diffusivity and Drying Characteristics of Tomato Slices during Convectional Drying (in English)

Abstract

 The drying characteristics of the tomato slices were investigated at 65, 70, 75 and 80 °C. The tomato samples were dried up to 2-3 % wet basis (w.b). The experimental data of the tomato samples were fitted to the six models; Page’s, Henderson & Pabis, Logaritmic, Wang & Sing, Midilli and Polynommial model. SSE, R2 and RMSE % values were used to determine the suitability of these models for describing the drying curves of tomato slices. Polynommial model gave better results compared to others. Effective moisture diffusivity values (Deff) were found between 5.86.10-9 and 2.505.10-8 m2/s for tomato slices and increasing drying temperature causes an increase in Deff values. The activation energy was found as 24.92 kJ/ mole. 

Keywords

• Curve fittings, drying kinetics, moisture diffusivity, tomato slices, polynommial model

Konveksiyonal Kurutmada Domates Dilimlerinin Kurutma Karakteristikleri Ve Efektif Nem Yayılım Değeri (İngilizce)

Abstract

Bu çalışmada, domates dilimlerinin 65, 70, 75 ve 80 °C’deki kurutma karakteristikleri araştırılmıştır. Domates numuneleri % 2-3 nem içeriğine kadar kurutulmuştur. Domates numunelerinin kurutma verileri, Page, Henderson & Pabis, Logaritmik, Wang & Sing, Midilli ve Polinom modelleri kullanılarak verilerin modellere uygunluğu denenmiştir. Domates dilimlerinin kurutma eğrilerinin modellere uygunluğunun belirlenmesinde SSE, R2 ve % RMSE değerleri kullanılmıştır. Polinom modelinin matematiksel eşitlikler içerisinde en uygun model olduğu belirlenmiştir. Domates dilimlerinin efektif nem yayılım değerlerinin (Deff) 5.86.10-9– 2.505.10-8 m2/s arasında değiştiği ve artan kurutma sıcaklığının Deff değerlerinde artışa neden olduğu belirlenmiştir. Domates dilimlerinin aktivasyon enerjileri 24.92 kJ/ mol olarak bulunmuştur.

Keywords

• Eğri uydurma, kurutma kinetiği, nem yayılımı, domates dilimleri, polinom modeli

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