Abstract
Raffinose pentahydrate (R5W) was dehydrated at 30oC under a KOH saturated solution environment to prepare raffinose tetrahydrate (R4W). During the dehydration, the sample was measured by differential scanning calorimeter (DSC) and peak distortion was observed. Thus, an intermediate between R5W and R4W was detected. Even during the water absorption of R4W to R5W, DSC peak distortion was observed, indicating that an intermediate between R5W and R4W was generated. However, the intermediates of the dehydration and water absorption processes were considered to be different hydrates, named R4'W and R5'W, respectively. Moreover, the melting points of the hydrates from R5W to raffinose low hydrate were measured. These results suggest the existence of raffinose hydrate lower than R3W.