Abstract
Form II is a kind of metastable crystalline form of trehalose anhydrate and is easily converted to the dihydrate crystal by absorbing water in a moist atmosphere at room temperature. It can be utilized as an edible and no poisonous desiccant and thus its efficient production from the dihydrate is significant from a viewpoint of industrial application. In this study, we attempt to extract crystal water from the dihydrate using supercritical CO_2 fluid. We examine the dependence of extraction efficiency on the extraction time, the temperature and pressure of the fluid. Consequently, we demonstrate that form II is produced from the dihydrate through supercritical CO_2 fluid extraction if appropriate temperature and pressure conditions (around 80℃ and 20 MPa) are given.
