Heat and mass transfer and deformation during chiffon cake baking

The structural transformation from a foam liquid to a porous solid during cake baking involves pore development and solidification, resulting in complex coupled heat transfer, mass transfer, and deformation processes. Studying the mechanisms can provide important references for understanding the physical processes of numerous foods containing gas pores. We constructed a multiphase flow-deformation model for chiffon cake baking, and validated its accuracy by comparing the experimental results of temperature and height. Based on the model, the heat transfer, mass transfer, and deformation characteristics were investigated. In the pore-closed region, the evaporation-diffusion-condensation process of water vapor enhances heat transfer, and its contribution to heat transfer has an equivalent thermal conductivity of up to 0.64 W/(m·K), which increases the heating rate. In the pore-opening region, the water vapor evaporates from the high-temperature, high-water activity region and is transported towards the lower-temperature region and external environment. This process enhances heat transfer and induces an evaporative cooling effect, resulting in a uniform temperature distribution that remains below 100 °C across the majority of the region. Cake expansion occurs in the low-viscosity, pore-closed region, and the water vapor generated at high temperatures serves as the primary driving force source, contributing up to 84.6%.