Flavor Release from Spray-Dried Powders with Various Wall Materials

By using the ramping method for humidity at a constant temperature, the release rates of d-limonene were investigated from spray-dried powders with various wall materials, such as maltodextrin (MD) (dextrose equivalent (DE) = 25 and 19), lactose (Lac), and sucrose (Suc). Spray-dried powders, which were sieved to the average powder size of 107–140 µm, contained d-limonene at about 90–97 mg/g-dry powder. d-limonene release profile was measured using a dynamic vapor sorption (DVS) system coupled gas chromatography at 30, 40, and 50 °C from 10% to 90% relative humidity (RH). The linear correlation was found between the release start humidity, sRH, of d-limonene release from the powder and the glass transition temperature of wall materials. The release rates for Suc and Lac increased rapidly at certain humidities and became the maximum rates. Then, these rates decreased gradually with increasing RH. This might have been due to the powder aggregation for Suc and to crystallization for Lac. The release behaviors significantly depended on the wall materials.