A Reaction Engineering Approach Model for Exploring the Drying Behavior of Single Droplets of Wolfberry Extracts

Abstract

ABSTRACT Wolfberry powder is an important raw material for medicine and functional food. In industrial practice, spray drying constitutes the predominant technique for Wolfberry powder production. Nevertheless, the fundamental mechanisms governing both moisture migration dynamics and particle morphology evolution during this dehydration process require systematic elucidation. In the current study, a reaction engineering approach model was applied to systematically explore the drying behaviors of single droplets made of Wolfberry extracts under various thermal conditions. Experimental measurements demonstrated temperature‐dependent reductions in both viscosity and surface tension, with maximum values obtained at 70°C. The droplet temperature change revealed three distinct phases: rapid heating phase, slow warming plateau, heating to AT (Ambient Temperature) phase. An empirical correlation between relative activation energy and moisture differential was obtained and a dimensionless shrinkage relationship was established, quantitatively describing how moisture dynamics and thermo‐physical properties synergistically determine the drying behaviors. These models can be used as a simplified and accurate tool to predict the drying behavior of Wolfberry extract droplets at different temperatures.