Local water content mainly varied with condensate absorption
and porous vapor condensation in the steamed buns. Based on
the estimated diffusivity properties, the water diffusion rate was
slower than the vapor transport rate in the pores, and, in the inner
region, the increase in water content primarily corresponded to the
variation in vapor condensation. Nevertheless, most increases in
surface water content resulted from the absorption of a large
amount of condensate on the surface, which then absorbed and diffused
into the region near the surface. As shown in Fig. 9, sigmoidshaped
wet basis water content curves were obtained at points a, b
and c. Those curves were similar to the temperature profiles (Fig. 6)
at corresponding locations, but the magnitudes of the curves were
The simulated spatial water content levels of a steamed bun without a PE
film wrap as a function of time: (a) simulated center water content; (b) simulated
water content at halfway to the center (2.5 cm from the surface); (c) simulated
water content at 1 cm from the surface; (d) simulated water content at 0.5 cm from
the surface; and (e) simulated surface water content.