  This work discusses results of experimental investigations of the specific
heat, $C$, of apple in a wide interval of moisture contents ($W=0-0.9$) and
temperatures ($T = 283-363$ K). The obtained data reveal the important role of
the bound water in determination of $C(W,T)$ behaviour. The additive model for
description of $C(W)$ dependence in the moisture range of $0.1<W<1.0$ was
applied, where the apple was considered as a mixture of water and hydrated
apple material (water plasticised apple) with specific heat $C_h$. The
difference between $C_h$ and specific heat of dry apple, $\Delta Cb=C_h-C_d$,
was proposed as a measure of the excess contribution of bound water to the
specific heat. The estimated amounts of bound water $W_b$ were comparable with
the monolayer moisture content in apple. The analytical equation was proposed
for approximation of $C(W,T)$ dependencies in the studied intervals of moisture
content and temperature.
