ABSTRACT
I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
II. Freezing Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
A. Definition and Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
B. Freezing Point Measurements and Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
C. Prediction Models of Initial Freezing Point . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
III. Ice Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
A. Ice Content, Freezable Water, and Unfreezable Water . . . . . . . . . . . . . . . . . . 107
B. Prediction Models of Ice Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
IV. Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
A. Enthalpy and Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
B. Prediction Models of Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
V. Specific Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
A. Specific Heat and Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
B. Prediction Models of Specific Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
VI. Latent Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
VII. Thermal Conductivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
A. Definition of Thermal Conductivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
B. Thermal Conductivity Measurement and Data . . . . . . . . . . . . . . . . . . . . . . . . 115
C. Prediction Models of Thermal Conductivity . . . . . . . . . . . . . . . . . . . . . . . . . . 117
VIII. Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
IX. Thermal Diffusivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
X. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Thermophysical properties control thermal energy transport, energy storage, and phase transform-
ations in food materials. Thermophysical properties of frozen foods are used to estimate the rate of
heat transfer and to calculate the heat load in processes such as freezing and thawing. In early cal-
culations and analyses associated with freezing and thawing, constant and uniform thermophysical
properties were primarily used. Those calculations and analyses were typically oversimplified and
inaccurate. Numerical analyses such as finite element and finite difference methods begun to be
used widely to analyze thermal food processes. Modern numerical analysis can account for nonuni-
form and varying thermophysical properties, which change with time, temperature, and location
during food processing. The benefits of modern numerical analyses increase the demand for more
accurate thermophysical properties of frozen foods.
