Investigation into Solar Drying of Moroccan Strawberry Tree (<i>Arbutus unedo</i> L.) Fruit: Effects on Drying Kinetics and Phenolic Composition

Abstract

Solar drying is affordable, requiring low energy and an eco-friendly method. Thus, the present paper studies the efficiency and characteristics of the indirect solar convective drying in the fruits of Arbutus unedo L. as well as its effects on the fruit phenolic compounds. The fruit samples were dried at 60 °C, 70 °C, and 80 °C. Phenolic compounds were investigated using a Liquid Chromatography platform. Experimental results revealed that the effective moisture diffusivity determined by Fick’s second law varied from 1.51 × 10−9 to 4.68 × 10−9 m2/s, and the activation energy recorded was 2203.62 kJ/kg. Both the total energy consumption and the specific electrical energy of the dried fruits decreased as temperature increased. The Midilli–Kucuk model was selected as the best-fitted model for drying Arbutus unedo L. Significant effect of temperature on phenolics was observed. The concentration of the phenolic compounds decreased by 15.54, 39, and 40.63% at 60, 70, and 80 °C, respectively.

Keywords

• convective solar drying
• <i>Arbutus unedo</i> L.
• energy efficiency
• polyphenols