Abstract
The microencapsulation of flavor, oil, or functional compounds is the technology of converting liquid materials into easy-to-handle solids. It also provides protection against degradative reactions and prevents the loss of the compounds. Among them, spray drying is the most popular method of producing food powders, which presents the challenge of removing water by vaporization while retaining the functional compounds. The relaxation behaviors of spray-dried powder during spray-drying and the flavor release at storage are reviewed in the research of spray-dried powder. Especially, the estimation of diffusion coefficient of water or flavor in matrix was discussed. The flavor release behaviors could be well correlated with Avrami equation. The morphology of spray-dried powder affected the release and oxidation of flavor. It is pointed out that the morphology of spray-dried powder is important properties in the relaxation behaviors of spray-dried powder.
