Calorimetric, mechanical, and thermomechanical properties have been measured on starch films with various glycerol/water contents. For calorimetric measurements, a continuous decrease in T-g was observed as glycerol increases from 0 to 25%. Mechanical properties exhibit a minimum of elongation at break for glycerol content similar to 12%. In slightly hydrated starch films not containing another plasticizer, a beta relaxation is detected by DMTA around -68 degrees C. This relaxation is modified by the presence of glycerol, the alpha relaxation of which appears in the same temperature range. Results are discussed comparing with the well-known antiplasticization effect in synthetic polymers such as PVC and PC. The combination of the plasticizer alpha mode and the polymer beta mode is considered.