One problem facing users of cocoa powders is the slow rehydration of the powder in liquids. This is reason why manufacturers of instant cocoa products improved this property by sugar addition. Nevertheless, the quantity of sugar added is generally around 80% which is recognized as a serious public health issue. Another problem experienced is the lack of methods to characterize cocoa powder rehydration properties. For the first time a dynamic method was developed to follow cocoa powder rehydration (and compared to classical methods used for milk powders). Then the quantity, nature and size of sugar were investigated in order to keep good functional properties and to lower sugar quantities.