## 3 Results and Discussion
### Breads' Characterization  
The physical properties of the gluten-free bread samples prepared with composite flour with and without pumpkin seed protein powder are shown in Tables 4 and 5. The breads prepared with higher amounts of water presented higher specific volumes, regardless of the flour used. The specific volume was positively correlated with C2 (R2 of 0.787 and \(p\) < 0.05). The breads prepared with the composite flours (RF + OFF and RF + OFF + PP) presented lower values of specific volumes compared to the control breads prepared with the RF. [PERSON] et al. [37] also reported specific volume decrease when using extruded flour to replace 10% of rice flour in gluten-free breads' formulation. Nonetheless, the specific volume of the breads prepared using the composite flours at a WA level of 75% was higher compared to the control bread with a lower amount of water (WA of 70%). [PERSON] et al. [38] reported the reduction in the specific volume of bread when partially substituting rice flour with pumpkin flour. They explained these results through the high fiber content derived from pumpkin flour, which weakened the dough structure, interfering with its ability to retain CO2 while baking. This observation is also supported by the study of [PERSON] [39], who compared the effect of pumpkin seed meal and pumpkin protein isolate addition on the bread-making properties of wheat flour and reported a lower reduction in the specific volume of bread in the latter case. No significant differences in terms of firmness were registered between the bread samples with a WA level of 70%, whereas at a higher WA level of 75%, RF substitution with OFF or OFF and PP had a stronger effect on crumb firmness, which increased significantly from 716.09 to 1263.38 g force (Table 4). Nonetheless, it should be noted that the firmness of the bread sample prepared with the RF + OFF + PP composite flour was better at WA 75% compared to WA 70%. The firmness of the bread prepared at 70% WA was correlated with C5 (R2 of 0.986 and \(p\) < 0.05), while the firmness of the bread with 75% WA was correlated with (C5-C4) (R2 of 0.997 and \(p\) < 0.05). [PERSON] et al. [40] tested the effect of different levels of gluten-free flour substitution with various dairy protein products on the quality of the bread and indicated a significant crumb softness reduction compared to the control. Moreover, [PERSON] et al. [20] reported the important increase in crumb hardness when supplementing wholegrain rice flour with 15% soy protein concentrate or powdered egg. [PERSON] and [PERSON] [41] reported that the addition of oat flakes to wheat flour supplemented with gluten resulted in an improvement in the specific volume and crumb firmness. Nonetheless, they reported a crumb firmness increase and a specific volume decrease for the sample with no gluten addition. The authors explained away these results by the large particle size of the oat flakes compared to that of wheat flour, with the presence of higher amounts of gluten being able to blur their effect. Additionally, [PERSON] et al. [42] investigated the bread-making potential of different oat varieties and found that the most important differences in bread quality were related to the crumb properties. Regardless of the WA level used for dough preparation, the substitution of RF with OFF and PP significantly decreased the brightness (L*) (\(p\) < 0.05) and increased the redness (a*) and yellowness (b*) (\(p\) < 0.05) of the gluten-free breads (Table 5, Figure 3). Our results are in good agreement with those of [PERSON] et al. [43], who tested the quality of high-protein breads and reported significant darkness, redness, and yellowness increases when incorporating soy and pea protein concentrates at various levels, ranging from 5 to 15%, into the wheat flour. The color difference (\(\Delta\)E) between the control breads, prepared with RF, and the breads with RF + OFF was 5.53-5.72, which is visible to the human eye [38].