Computer modeling of sugar crystallization during drying of thin sugar films

摘要

A computer model was deveoped to predict drying and crystallizaiton during processign of thin sugar films under the condtions of importance for sugar-coated cereals. Thue hree-dimensional modle anlayzed simultaneous heat and moisture transfer, accounting for shirinkage, with temeprature and moisture-dependent transport properties. Crstyal growth was evaluated from crystallization kientics based on supersaturtion and temperautre. The infleunce of growth on the solution concentration and drying were taken into account. Concentration profiles around the growing crystals druign drying of the thin films were evalauted. The model predics a concentration reduction around the grwoing crystals, and film temperatures tha are hgiher than the drying temperature (as a result of the release of fusion heat). A phenomenon of case hardening was observed for dried films with a hgih density of seeds on surface.