Abstract

It was tried to prepare the capsules containing L-cysteine with the melting dispersion cooling method. Tripalmitin was selected as the shell material in order to keep out water and a few fatty acid esters such as ethyl laurate, ethyl stearate, ethyl myristate, ethyl oleate, ethyl palmitate and bees wax were added in the shell material as the modification materials in order to improve the water proof of the capsule shell. Furthermore, the capsules were coated by the coating materials such as oleic acid, ethyl oleate, triolein and ethyl laurate. It was investigated how the concentration of oil soluble surfactant and the combination of the shell material with both the modification materials and the coating materials affected the characteristics of capsules such as the content and the release feature of core material, the water proof and the swelling degree of capsules. With increasing the concentration of oil soluble surfactant, the released ratio decreased, become minimum and then, increased. The content could be increased by addition of modification materials. It was found that the released ratio was considerably depressed by ethyl laurate and ethyl palmitate as the modification materials and by oleic acid as the coating material and promoted by bees wax as the modification materials.