The invention relates to a process for preparing a randomly-bonded polysaccharide, comprising as ingredients a saccharide, a polyol and an acid serving as a catalyst, the process comprising the steps of feeding the ingredients into a reactor in order to dehydrate the fed ingredients to an essentially anhydrous syrup, polycondensating the essentially anhydrous syrup at elevated temperatures in the said reactor while removing the reaction water, wherein the reactor is a mixing kneader device with counter-acting blades, wherein during the feeding step the saccharide, the polyol and the acid serving as catalyst are simultaneously or consecutively fed to the reactor, and in that during the dehydratation and polycondensation step the free water and reaction water is removed from the mixing kneader device by kneading and mixing the fed ingredients and the subsequent essentially anhydrous syrup under reduced pressure in the reactor, and during the polycondensation the essentially anhydrous syrup is continuously kneaded in the kneader reactor until the required degree of polymerization is obtained.