One of the most important product properties is the specific heat, or, in
the case of frozen food, the apparent specific heat. Below food's freezing point,
the sensible heat from temperature change and the latent heat from fusion of
water must be considered. Because latent heat is not released at constant
temperature, but rather over a range of temperatures, an apparent specific heat
must be used to account for both the sensible and latent heat effects. A slightly
simpler apparent specific heat model, which is similar in form to that of
Schwartzberg (2006), was developed by Chen (1985).