## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Parameter** & **3.5P125** & **3.5P150** & **7P125** & **7P150** \\ \hline Outlet temperature (\({}^{\circ}\)C) & 74.2 (0.8) \({}^{\mathrm{d}}\) & 86.5 (0.5) \({}^{\mathrm{b}}\) & 77.8 (0.8) \({}^{\mathrm{c}}\) & 92.8 (2.1) \({}^{\mathrm{a}}\) \\ Product yield & & & & \\ (g solutes in the powder/100 g & 31.86 (0.02) \({}^{\mathrm{c}}\) & 41.5 (1.8) \({}^{\mathrm{a}}\) & 28.2 (0.7) \({}^{\mathrm{d}}\) & 36.6 (0.8) \({}^{\mathrm{b}}\) \\ solutes in the mixture) & & & & \\ Drying ratio & 8.8 (0.2) \({}^{\mathrm{a}}\) & 8.95 (0.19) \({}^{\mathrm{a}}\) & 6.48 (0.09) \({}^{\mathrm{b}}\) & 6.56 (0.09) \({}^{\mathrm{b}}\) \\ Productivity (g/h) & 67.1 (0.9) \({}^{\mathrm{b}}\) & 66.5 (0.9) \({}^{\mathrm{b}}\) & 84.1 (1.7) \({}^{\mathrm{a}}\) & 83.7 (1.4) \({}^{\mathrm{a}}\) \\ \hline \hline \end{tabular}  
* Letters indicate homogeneous groups established by the ANOVA (\(p<0.05\)) within rows: 3.5P125 or 3.5P150, powder with 3.5% of pea protein concentration spray dried at 125 or 150 \({}^{\circ}\)C, respectively; 7P125 or 7P150 powder with 7% of pea protein concentration spray dried at 125 or 150 \({}^{\circ}\)C, respectively.  
\end{table} 
Table 2: Outlet temperature, product yield, drying ratio, and productivity mean values (and standard deviation) of spray-dried powders. is related to its free-flowing behavior and stability during storage, because of its effect on the glass transition and its behavior during crystallization [24]. CP content was higher in powders with 7% P than samples with 3.5%. Nevertheless, slight differences were observed between the 125 or 150 \({}^{\circ}\)C SD, with the CP value higher for powder obtained at 150 \({}^{\circ}\)C. This is because of lower x\({}_{\rm w}\) of samples spray dried at 150 \({}^{\circ}\)C. The spray-dried samples' WAI increased significantly when higher P % was used (_p_ < 0.05). However, the powders' WSI decreased significantly when higher P % was used (_p_ < 0.05). The WAI indicates the immobilized water amount by the samples [44], whereas the WSI is related to the soluble solids amount present in the product as a function of the solubilization of starches, sugars, proteins, fibers, and maltodextrin [45]. Therefore, using a higher level of P increased the amount of water immobilized by the samples and reduce the soluble solids present in the product. The spray-dried temperature effect only was observed in WSI for samples with 7% P, showing lower values at 150 \({}^{\circ}\)C. There was a significant (_p_ < 0.05) increase of \(\varepsilon\) and decrease of \(\rho_{\rm b}\) because of high P concentration in powders and high spray-dried temperatures. Porosity plays a key role in the agglomerate strength of dried foods [46]. Furthermore, a greater porosity (and lower bulk density) corresponds to a freer-flowing powder with a greater air volume distributed among particles, as well as being more soluble [46, 47]. Other studies showed similar results as porosity increases when biopolymers were added [33, 39]. When studying each P concentration (3.5 or 7%), there was a significant effect of SD temperature on \(\rho_{\rm b}\) and \(\varepsilon\) (_p_ < 0.05). The higher spray-dried temperature caused a lower \(\rho_{\rm b}\) and higher \(\varepsilon\) of the powders; also observed but from another author in spray-dried Amaranthus [25]. Figure 1 presents the evolution of hygroscopicity of beetroot powders along 7d. Hygroscopicity is the capacity of a powder to absorb water from the environment; absorbed water influences the storage stability of products. Samples with lower hygroscopicity are easier to handle and package. Samples spray dried at 125 \({}^{\circ}\)C continuously and linearly collected water during the assay. However, the samples spray dried at 150 \({}^{\circ}\)C captured water more quickly in the first 5 days and then stabilized. At the end of the hygroscopicity study, samples are ordered from low to high hygroscopicity, as 7P150 < 7P125 < 3.5P150 < 3.5P125. According to [PERSON] et al.