3.3.5. Cake texture profile analysis
The firmness of cakes made from unheated and heated sorghum
flour is shown in Fig. 4. The cake firmness decreased as the time of heat treatment increased. The control sorghum flour had the
highest firmness (635 g), while the heat treated sorghum flour at
95 C for 45 min had the lowest (555 g). This decrease in firmness
may be related to the amount of air incorporated into the cake
batter during mixing. As previously mentioned, heat treatment
reduced the specific gravity of the cake batter. This increase in
amount of air bubbles in the batter system seems to translate into a
tender baked product. Heat treatment of flours has been shown to
improve texture, grain, volume, and eating quality of cake
(Hanamoto & Bean,1978; Russo & Doe,1970). Russo and Doe (1970)
showed that the optimum heat treatment temperature of flour is
120 C to improve baking performance in high ratio layer cakes.
While holding time was not determined to be a critical factor, this
study illustrated that too high treatment temperatures had deleterious
effects on baking texture and flavor. Further work by Fustier
and Gelinas (1998) revealed that heat treatment increased cohesiveness
and springiness while reducing gumminess in final cake
texture.