Thermal conduction can be induced near the heating plane along the one-dimensional axis (x-axis) in freshly prepared albumen foam of egg (meringue) during heating in a metal vessel at 105°C. Egg albumen was whipped at about 800 rpm using a kitchen mixer for 90, 180, 240 and 300s at room temperature. In the freshly prepared samples, the air bubbles increased in number, but decreased in size as whipping time increased. As all samples were prone to instability over time, all measurements were completed within 50 min after preparation. Steady flow properties and creep behavior were measured to characterize each albumen foam preparation based on plasticity. Both plastic viscosity and Casson's yield value increased with increasing whipping time. Thermal conductivity λ and density ρ decreased, while the heat capacity at constant pressure C_p increased, with increasing whipping time, giving thermal diffusivity, α=λ/C_p·ρ. Thus, thermal diffusivity of each sample decreased with increasing whipping time. The relationship between the increase in temperature and heating time for all albumen foam samples conformed to an exponential equation based on the assumption that retardation plays a significant role in thermal conduction of albumen foam. This retardation is characterized by the retardation time τ (x).

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