Effect of capsule size on permeability of gelatin-acacia microcapsules toward sodium chloride.

The effect of capsule size on the permeability of gelatin-acacia microcapsules toward sodium chloride was investigated. Gelatin-acacia microcapsules containing olive oil were prepared by phase separation. The encapsulated olive oil was extracted with acetone and the acetone-loaded microcapsules dispersed in acetone were fractionated by a series of mesh screens. The core material of acetone than was replaced by water. The permeability of each capsule fraction toward sodium chloride was estimated from the change in electrical conductance with time of the mixture of microcapsule suspension and sodium chloride solution. The permeability decreased with decreasing capsule size. Structured water in and around the capsule wall may be the cause of the observed size effect.