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The change in the dielectric properties of frozen 200 g kg −1 maltodextrin solutions upon warming has been recorded using a capacitance meter and a dielectric thermal analysis instrument. The capacitance and permittivity increased by several orders of magnitude after melting, and higher values were obtained at a higher measurement frequency or with added NaCl, while a marked increase (labelled T rise ) was seen close to the glass transition temperatures measured by differential scanning calorimetry. The transition temperatures shifted to more negative values by 4-6 • C upon the addition of 0.1 mol kg −1 NaCl, consistent with the freezing point depression of the freeze-concentrated solutions. INTRODUCTIONMaltodextrins are produced by the controlled hydrolysis of starch to generate a mixture of oligosaccharides of α-D-glucose of varying chain lengths. 1 They are classified by their dextrose equivalence (DE), a measure of total reducing sugars compared to glucose with a value of 100, which is related to the average molecular weight (M n ) as follows: