THESIS

1) Specific gravity
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Specific gravity of the butter cake form and batter were
significantly affected by the addition of HFCS-55. The amount of HFCS, which was
higher than 40% replacement had significant (P≤0.05) effect on the specific gravity of
the butter cake form and batter (Table 19). The higher amount of HFCS replaced (60,
80 and 100%) for sucrose tended to lower specific gravity of the butter cake form and
batter (0.27, 0.25, 0.23 and 0.86, 0.78, 0.76 g/ml, respectively). Measurement of a
batter’s specific gravity estimates the amount of air incorporated into a batter such
that a lower specific gravity is indicative for a batter with more air and viscosity
(Penfield and Campbell, 1990a). A viscous batter helps keep air bubbles from rising
out of the batter while a less viscous batter with a higher specific gravity allows large
bubbles to coalesce, rise up to the surface and leave the batter (Bath et al. 1992; Kim
and Walker, 1992). The specific gravity of a batter can also be related to a cake’s
volume (Penfield and Campbell, 1990d). That is, the greater the total cake volume,
the less its weight per unit volume and the lower its specific gravity. Adequate air
incorporation is necessary to produce a cake of high volume.
2) Cake color
Crust color also significantly affected (P≤0.05) by the
replacement of sucrose with HFCS. The Hunter L*, a* and b* values correspond to
lightness, redness, and yellowness, respectively. Table 19 shows that the crust color
parameter a* and b* values of HFCS butter cake increased with increasing HFCS
content. The red and yellowness occurred during baking reaction in 100% HFCS
more than 100% sucrose. The crust color of control (100% sucrose) cake was lighter
(P≤0.05) and less red (P≤0.05) than all other cakes. Crust L*, a* and b* values were
not significantly different for 20, 40, 60 and 80% HFCS cakes. Similar, it has been
reported that browning reaction affects color during thermal processing of cookie and
bread crust (Wang and Peng, 1998). During the heat treatment, sucrose and starch
may hydrolyze respectively into glucose and fructose, or maltose and glucose. In
addition, the formed of HFCS
that less thermo-stable than sucrose and newly formed