Determination and Mathematical Modeling of Drying Kinetics of Avocado Slices by Tunnel Type Solar Drying and Microwave Drying Method

Abstract

Within the scope of this study, drying studies of avocado fruit using a solar tunnel dryer were experimentally carried out in Isparta conditions. At the same time, avocado slices were dried in a laboratory-dimensioned household microwave dryer. In the experiments, avocado fruits were studied at 4 mm slice thickness. Also, time dependent moisture content, drying rate and drying characteristics of avocado slices are reported. Avocado fruits with an initial moisture content of 71.51±0.35% (w.b.) were dried both by solar drying method and by microwave drying method until their moisture content was 14.23±0.16% (w.b.). Drying processes took approximately 3 days for avocados with 4 mm slice thickness in the solar powered system. In the microwave dryer, dehydration times were founded as 76, 34 and 14 minutes, respectively, at 180W, 360W and 540W microwave powers. The drying data obtained from the experiments were performed to 8 different model equations. While determining the best model equation, coefficient of determination (R2) should be the largest, standard error of prediction (SEE), mean square error (RMSE) and chi-square (χ2) should be minimum. In both drying methods, the most suitable dehydration model equation was founded as the Alibaş model equation.

Keywords

• avocado
• solar tunnel dryer
• microwave
• modelling

Güneş Enerjili Tünel Tipi Kurutucu ve Mikrodalga Kurutma Yöntemi ile Avokado Dilimlerinin Kuruma Kinetiğinin İncelenmesi ve Matematiksel Modellenmesi

Abstract

Bu çalışma kapsamında, tünel tipi güneş enerjili kurutucu ile Isparta şartlarında avokadonun kurutma denemeleri deneysel bir şekilde gerçekleştirilmiştir. Ayrıca avokado dilimleri ev tipi mikrodalga destekli konvektif kurutucuda kurutulmuştur. Denemelerde avokado meyveleri 4 mm dilim kalınlıklarında çalışılmıştır. Bunlara ek olarak, avokado dilimlerinin zamana bağlı olarak nem içeriği, kuruma hızı ile kuruma karakteristikleri rapor edilmiştir. İlk nem içeriği %71.51±0.35 (y.b) olan avokado meyveleri, hem tünel tipi güneş enerjili kurutma yöntemi ile hem de mikrodalga kurutma yöntemi ile nem içeriği %14.23±0.16 (y.b) olana kadar kurutulmuştur. 4 mm dilim kalınlığına sahip avokadoların güneş enerjili tünel tipi kurutma sisteminde kurutma işlemleri yaklaşık 3 gün sürmüştür. Mikrodalga kurutucuda kurutma süreleri 180W, 360W ve 540W mikrodalga güçlerinde sırasıyla 76, 34 ve 14 dakika olarak bulunmuştur. Denemelerden elde edilen kurutma verileri, 8 farklı matematiksel model eşitliğe uygulanmıştır. En iyi model eşitliği belirlerken, R2’nin en büyük, SEE, RMSE ve χ2'nin en küçük olması gerekmektedir. Her iki kurutma yönteminde de, en uygun kuruma modeli, Alibaş model eşitliği olarak bulunmuştur.

Keywords

• avokado
• güneş enerjili tünel tipi kurutucu
• mikrodalga
• modelleme

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