3.1.3. Chemical composition and technological properties of the raw
materials and blends
The protein content was over 12% for all raw materials evaluated
(Table 1), except BPG, which had a lower value (11.75%). Stauffer
(1993) suggests that the protein content of flours used to make bread
should range between 12% and 14%, also when it is used in the production
of bread from frozen dough. The replacement of CWF by 5% EWF
(BEW) did not promote changes in protein content, although the type
of protein found in the wheat flour is more important than its content
(Añón, Le Bail, & León, 2005). The lower protein content found in BPG
occurred because replacing part of the wheat flour by PGS caused protein
dilution in the blend, which may in turn affect the dough structure
and gas retention during proofing and baking. Regarding the ash content,
there was no significant difference between the analyzed samples.
The ether extract contentwas similar for CWF and blends (BEWand
BPG), but for EWF, it was 0.39% and significantly lower than the others,
probably because the temperature used in the extrusion process promoted
the complexation of lipids with starch and/or proteins, reducing
their extraction by the method used in this study, according to Chang,
Schmiele, and Martinez-Bustos (2009).
The amount of damaged starch in the flour (CWF) and blends
(BEW and BPG) evaluated did not differ significantly by the Tukey test
(P ≤ 0.05). Therefore, even with the introduction of EWF and PGS in
blends, these raw materials did not contribute to elevate the damaged
starch content in relation to CWF. These values found are in accordance
with the 5 to 10% range indicated by literature for bread production
(Sluimer, 2007).