Abstract
For aqueous solutions of various mono-, di-, and oligosaccharides thermodynamic properties have been investigated at low temperatures using differential scanning calorimetry. The amount of unfrozen water, Uw, increases linearly with the glass transition temperatures of anhydrous carbohydrates. Uw also shows a linear relationship with partial molar isentropic compressibility K^0_<S,2>. More unfrozen water is induced in the presence of a given carbohydrate, with more negative value of K^0_<S,2>, acting as a structure breaker to the three dimensional hydrogen-bond network of water. Relative amount of unfrozen water for disaccharides studied is associated with the combination of constitutive monosaccharides and attendant molecular structure features such as the position and type of the glycosidic linkage between the constituent units. These results suggest that for a series of the above thermodynamic parameters there is a common systematic dependency on molecular structures of carbohydrates.
