## 4 Discussion  
The specific volumes of the experimental formulations are comparable to those reported in other studies, such as 1.85 cm\({}^{2}\)/g for GFB prepared with 100% rice flour [23]. However, [PERSON] et al. [27] reported lower values of specific volumes for different breads made with wheat flour in combination with SF, with values of 1.30 cm\({}^{3}\)/g for GFB prepared with 75% WS and 1.40 cm\({}^{2}\)/g for GFB prepared with 75% BS. According to [PERSON] et al. [28], the increase in SF content and consequently fiber content is a factor that is mainly responsible for the decrease in the specific volume of GFB prepared with SF. However, this effect was not observed in this study, possibly because of the water adjustment that was also conducted. Previous studies showed that when up to 70% SF is used in combination with rice, potato, cassava, or corn starches, GFB with promising physical characteristics could be produced [29; 30]. The results of the present study show that it is possible to use both 100% SF and 75% SF in combination with potato starch and obtain GFB with greater volume and softness. Regarding acceptability, [PERSON] et al. [31] reported high scores (> 7 in a 10 cm hybrid hedonic scale) for appearance, color, texture, and overall liking of GFB made with 100% WS. Our results show that it is possible to obtain scores greater than 7 for these attributes using 100% BS in the formulation of GFB. When comparing formulations made with WS or BS and conventional GFB formulations in terms of acceptability, the GFB resulting from Trials 1, 3, 5, and 6 obtained acceptability scores similar to those obtained by GFB prepared under the same experimental conditions with 100% rice flour and by GFB prepared with 50% rice flour and 50% potato starch, ranging from 7.6 to 8.5 [29]. Therefore, GFB made with 50% and 75% whole grain SF has acceptability similar to conventional GFB. To verify whether there was an increase in the nutritional composition of the GFBs made with WS or BS, they were compared with two conventional GFB formulations. [PERSON] et al. [22] prepared GFB with 100% rice flour containing 52.2% moisture, 1.2% ash, 4.1% lipid, 5.0% protein, 2.1% dietary fiber, and 35.4% available carbohydrates. [PERSON] et al. [23] made GFB with 50% rice flour and 50% potato starch containing 48.6% moisture, 1.32% ash, 4.2% lipid, 4.10% protein, 2.30% total fiber, and 39.5% available carbohydrates. Observing the composition of these conventional breads, GFB made with 75% and 100% WS/BS showed an increase in protein and fiber content. Figure 3: Dendrogram obtained by hierarchical cluster analysis for data of gluten-free bread based on (**a**) white sorghum (WS) and (**b**) bronze sorghum (BS) flours and different water (W) levels. Bread ID: WS, white sorghum; BS, bronze sorghum; W, water. The letters and numbers indicate the ingredient proportions in the flour weight basis (g/100 g). According to the criteria of Codex Alimentarius [32], these GFBs made with 50% and 75% WS/BS can be classified as a source of fiber because the fiber content is higher than 3 g per 100 g, while GFB made with 100% WS/BS can be classified as high in fiber because the content of this nutrient is higher than 6 g per 100 g.  
Compared to the bread solely made of BS flour that was developed by [PERSON] et al. [33], the GFB made from our formulations containing 100% WS or BS have a better appearance and are characterized by a crumb of uniform distribution of alveoli. This result is possibly due to the higher levels of water used in the formulations (100 to 140%) since [PERSON] et al. [33] used a concentration of 95% water fwb and, according to [PERSON] and [PERSON] [18], the increase in water content is important to ensure the appropriate conditions of the dough viscosity, starch gelatinization, and protein denaturation during the baking process. The formulations developed in this study also contained hydrocolloids (xanthan gum and carboxymethylcellulose), unlike those presented by [PERSON] et al.