Development of Apple Vinegar Microcapsules Using Low Glycemic Wall Materials Palatinose and Inulin: A Mixture Design Approach

Apple vinegar is a functional ingredient rich in acetic acid; however, its incorporation into powdered food products is limited by its volatility, acidity, and heat sensitivity. This study investigated the spray-drying microencapsulation of apple vinegar using inulin and palatinose as wall materials. A two-component simplex lattice design was applied to compare encapsulation efficiency (EE), moisture content, hygroscopicity, and powder morphology among different carrier formulations. During preliminary spray-drying trials, high-palatinose formulations exhibited pronounced wall deposition at an inlet air temperature of 130 °C. Reducing the inlet temperature to formulation-specific values improved processability and enabled powder recovery. Under their respective spray-drying conditions, the investigated formulations exhibited distinct physicochemical properties. Moisture content ranged from 2.29% to 4.22%, hygroscopicity from 0.29 to 2.28 g/100 g, and EE from 19% to 95%. The 100% inulin formulation exhibited the highest EE and a more uniform particle distribution, whereas the 100% palatinose formulation showed lower residual moisture but higher hygroscopicity. The fitted Scheffé mixture models adequately described the observed formulation-dependent responses. Because inlet temperature was adjusted according to formulation processability, the observed differences should be interpreted as formulation performance under the applied formulation-specific spray-drying conditions rather than as effects attributable exclusively to carrier composition. These findings support the potential use of inulin and palatinose as low-glycemic carrier materials for producing spray-dried apple vinegar powders.