Effect of Pre-Treatments on the Qualities of Banana Dried by Two Different Drying Methods

Abstract

This study investigates the impact of various pre-drying treatments and drying methods on the physicochemical, phytochemical, and sensorial quality of dried bananas. To achieve this goal, four pretreatment solutions were used before drying to enhance the quality characteristics of banana slices: citric acid 1% and ascorbic acid 1%, sucrose 10%, sodium bisulphate 0.5%, and lemon juice 5% and acetic acid 0.5%. Two drying methods were applied, sun drying (SD) and tunnel drying (TD). The dried slices were evaluated for moisture, total acidity, water activity (aw), browning index, rehydration ratio (RR), reducing sugar, ascorbic acid, total phenol, and DPPH %, as well as sensory attributes (color, odor, taste, texture, and overall acceptability). The results showed that the retention of acid content, ascorbic acid, total phenolics, and DPPH in slice samples dried in TD was higher than that in SD. The browning index values in the TD samples were lower than those in the SD samples. Moreover, the TD samples showed a higher RR than the SD samples. It is noted that the pretreatment solutions used have an important role in improving the final quality characteristics of dried banana slices. The results of the sensory evaluation revealed a significant difference in the degrees of color and texture for the slices pretreated with sodium bisulphate. Meanwhile, the rates of taste and odor were significantly higher for the sucrose-pretreated slices. TD can improve the drying kinetics, shorten the drying time, and maintain the quality of the dried slices.