Comparative study of pretreatment on microwave drying of Gala apples (Malus pumila): Effect of blanching, electric field and freezing

• DOI: 10.1016/j.lwt.2022.113693
• Publication Date: 2022-06-29T12:55:33Z
• Authors: Karim Kriaa; Ahmed F. Nassar
• Keywords: Blanching; Malus; Cell structure

Microwave drying is particularly recommended for thermosensitive products such as food in order to preserve all their properties. During drying, some fruits tend oxidize and brown, losing flavor vitamins A C. To reduce oxidation the quality of dried product, a pretreatment by placing fruit an acid solution (citric or ascorbic) recommended. On other hand, blanching, freezing electric field treatment alters cell structure, allowing moisture escape more easily rehydrate quickly. An experimental study was conducted see effect different methods on kinetics microwave-dried apple samples. For kinetics, no significant observed blanched treated However, reduction time value 14.6–20.3% frozen In best (lowest ΔE, lowest BI, highest WI) sample 5% citric at 60 °C. Finally, surface structure samples studied scanning using Scanning Electron Microscope (SEM).