Controlled Release of Fluidized Bed-Coated Menthol Powder with a Gelatin Coating

We estimated the release properties of fluidized bed-coated menthol powder by static headspace analysis and by relating the release properties and the properties of the coating. Powder was spray-dried onto different coating materials such as gelatin, an oil-gelatin emulsion, modified starch, and Aquacoat (R) ECD in a fluidized bed system, and then submerged in water at 37 degrees C with a shearing force. The release properties of encapsulated menthol powder were estimated over 15min compared with spray-dried powder. The microencapsulation efficiency of menthol powders was determined, as well as the density, surface tension, viscosity, and powder contact angle of coating materials. The gelatin emulsion was found to be a potential coating material for controlling menthol release from the coating powder and high microencapsulation efficiency (90.44%) achieved; 60% of the menthol powder was released after 11min. These results indicate that the solubility and integrity of the coating is important to the success of the fluidized bed-coating process for controlled release of flavor from this degradation-activated release system.