Effects of different drying methods on the drying kinetics and quality characteristics of Orah (Citrus reticulata) slices

This study evaluated the effects of microwave vacuum drying (MVD), microwave drying (MD), heat pump drying (HPD), hot air drying (HAD), and freeze drying (FD) on the drying kinetics, and changes of physicochemical properties and bioactive compound of Orah slices. In the analysis of the seven models examined, the Page model was found to be the most accurate in describing the changes in moisture content during the drying process. MD was significantly faster than HAD and HPD, reducing drying time by 95.12 and 94.17%, respectively, and increasing the effective moisture diffusion rate by 94.40%. Microscopic analysis showed MVD samples had large, uniform pores, which improved moisture diffusion. FD and MVD preserved bioactive nutrients and demonstrated superior antioxidant activity over other methods. MVD produced products with balanced texture, minimal color change, and the shortest drying time of 38 min. MVD can be a promising dehydration technique for producing high-quality Orah products.