Effect of ice structuring proteins from winter wheat on thermophysical properties of dough during freezing

Ice structuring proteins (ISPs) are proteins that can modify and inhibit the growth of ice. ISPs may improve the quality of frozen dough by stabilizing ice crystals and maintaining the texture of frozen dough. In this study, effects of ISPs from winter wheat were examined on the thermophysical properties of dough, which include freezing point depression, freezable water fraction, apparent specific heat, and effective thermal conductivity. The thermophysical properties were measured by differential scanning calorimetry (DSC) and line source probe methods. The results showed that, compared to the control, adding 0.6% ISPs induced a maximum freezing point depression of 0.23 °C and decreased the amount of freezable water by 8%. ISPs had little effect on the apparent specific heat and the effective thermal conductivity in the unfrozen ranges. However, the thermophysical properties in the frozen ranges were significantly affected by ISPs. The determined thermophysical properties are important to model heat transfer during freezing of dough.