Effects of Temperature on Drying Characteristics Green Olives (Turkish with English Abstract)

Abstract

In this study, the effect of air temperature on drying kinetics and quality of sliced green olives were examined during air drying. Fermented green olive slices having moisture content of 75% (wet basis) were dried to 4% moisture content by using laboratory scale tray drier. Drying process was realized at three different drying air temperatures (40, 50 and 65 °C) and at constant air velocity of 1.3 m/s. Increasing drying temperature leads to lower drying time. Changes in color and water activity measurements of dried samples were evaluated. Higher drying temperatures caused increasing of browning of dried olives.

Keywords

• Drying, green olive, diffusion coefficient, tray drier  

Yeşil Zeytinlerin Kurumasında Sıcaklığın Etkisinin İncelenmesi

Abstract

Bu çalışmada dilimlenmiş salamura zeytinlerin tepsili kurutucuda kurutulmasında kurutma sıcaklığının kuruma kinetiğine ve bazı kalite özelliklerine etkisi incelenmiştir. Yaş temelde %75 nem içeren dilimlenmiş yeşil zeytinler  %4 nem içeriğine,  40, 50 ve 65°C' deki sıcaklıklarında ve 1,3 m/s hızındaki hava kullanılarak laboratuar ölçekli tepsili kurutucuda kurutulmuştur. Yüksek sıcaklıkta gerçekleştirilen kurutma denemelerinde işlem süresinin daha kısa olduğu görülmüştür. Kurutulmuş ürünler renk ve su aktivitesi değerleri ölçülerek kalite açısından değerlendirilmiş, sıcaklık artışının renkte koyulaşmaya neden olduğu saptanmıştır.

Keywords

• Kurutma, renk, zeytin, difüzyon katsayısı, tepsili kurutucu

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