Change in the Specific Heat Capacity of Parenchymal Tissues of Apples due to Dehydration

We present the results of measurements of the heat capacity of parenchymal tissues of apples by the differential scanning calorimetry method. An analytical dependence of the specific heat capacity of these tissues on their temperature (10–90°C) and moisture (6.8–90%) is proposed. We have considered the boundary conditions under which it is possible to calculate the heat capacity of moist parenchymal tissues of apples containing simultaneously free and bound water by an additive model. Reliable values of the heat capacity of tissues containing only bound water can be obtained only experimentally. In parenchymal tissues of apples with a low moisture content (0.6–0.43%) in the positive temperature range, a stepwise change in the heat capacity has been revealed.