## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c} \hline  & **3.5P125** & **3.5P150** & **7P125** & **7P150** \\ \hline L\({}^{*}\) & 23.1 (0.3) d & 25.91 (0.13) c & 26.8 (0.6) b & 28.5 (1.3) a \\ a\({}^{*}\) & 34.66 (0.09) c & 36.80 (0.04) a & 36.1 (0.4) b & 35.7 (0.7) b \\ b\({}^{*}\) & 2.73 (0.12) a & 1.99 (0.03) b & 1.52 (0.04) c & 0.88 (0.12) d \\ C\({}^{*}\) & 34.765 (1.04) c & 36.85 (0.04) a & 36.2 (0.4) b & 35.8 (0.7) b \\ h\({}^{*}\) & 4.5 (0.2) a & 3.10 (0.04) b & 2.40 (0.05) c & 1.4 (0.2) d \\ \(\Delta\)E\({}_{1}\) & & 3.61 (0.08) a & & 2.5 (0.6) b \\ \(\Delta\)E\({}_{2}\) & & & 4.2 (0.6) a & 3.6 (0.5) a \\ \hline \end{tabular}  
* The same letter in superscript within a row indicates homogeneous evats established by ANOVA (\(p<0.05\)), L\({}^{*}\)(lightness), a\({}^{*}\) (red/green coordinate), b\({}^{*}\) (yellow/blue coordinate), C\({}^{*}\) (chroma), and h\({}^{*}\) (tone); \(\Delta\)E\({}_{1}\) (total color difference between samples with the same P concentration and different spray-dried temperature) and \(\Delta\)E\({}_{2}\) (total color difference between samples with the same spray-dried temperature and different P concentration); 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 4: Mean values (and standard deviations) of color coordinates (L\({}^{*}\), a\({}^{*}\), b\({}^{*}\), C\({}^{*}\), and h\({}^{*}\)) and total color differences (\(\Delta\)E\({}_{1}\) and \(\Delta\)E\({}_{2}\)) of beetroot powders. Figure 1: Evolution of hygroscopicity of each powder sample along assay time: 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. powdered particles are also smaller with a higher particle density. This is likely related to more free-flowing powders, because samples with 7% P and spray dried at 150 \({}^{\circ}\)C were more porous (Table 3). Similar to [PERSON] and [PERSON] [52], increasing the solids content in the feed to be spray dried leads to a smoother particle surface. From the micrographs, the average powders particle size was between 34 to 94 \(\upmu\)m. Mean values of particle size (and standard deviation) of spray-dried samples were 94 (16), 56 (7), 48 (6), and 34 (5) \(\upmu\)m for 3.5P125, 3.5P150, 7P125, and 7P150, respectively. Therefore, the effect of increased P % and spray-dried temperature reduced the particle size. These results agree with the findings of [PERSON] et al. [53], studying maltodextrin concentration in spray-dried pitaya fruit powders (effect of solute addition) and with [PERSON] et al. [54], studying the effect of spray-dried temperature on milk protein concentrates. Figure 3: FESEM micrographs of studied samples: 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. Figure 2: Appearance of studied beetroot powder samples: 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. Mean values of total phenol, betacyanins, betaxanthins content, and AC of beetroot feed and spray-dried samples are showed in Table 5. Total phenol, betacyanins, betaxanthins content, and AC of beetroot spray-dried samples were lower than the beetroot feed for each formulation.