control sorghum flour compared to the heat treated flour. Significant
differences (p < 0.05) were found among the treatments. The
heat treated sorghum flour for 30 min at 125 C had the lowest
specific gravity, while the control untreated sorghum flour had
the highest. In general, the specific gravity decreased as the
temperature/time of heat treatment increased. This decrease in
specific gravity may mean more air was incorporated into the
batter system. The specific gravity of a batter has a direct influence
over the final cake volume (Kim & Walker, 1992). Lower weight
per unit volume along with lower specific gravity translates into
greater total cake volume. Specific gravity is a gauge of the
amount of air is incorporated into the batter (Pyler, 1988). A more
viscous batter with lower specific gravity prevents large air bubbles
from coalescing and leaving the batter from the surface. The
following sections will compare the volume and crumb structure
of cakes.