## 3 Results
### Relations between Variables  
The correlations between variables are presented in Table 4. Foaming capacity was positively correlated with the fat (\(r=0.52\), \(p<0.05\)) and ash contents (\(r=0.78\), \(p<0.05\)) and negatively with carbohydrates (\(r=-0.37\), \(p<0.05\)). Oil absorption capacity was correlated at \(p<0.05\) significance level with fat (\(r=0.67\)), ash (\(r=0.84\)), protein (\(r=-0.50\)) and foaming capacity (\(r=0.72\)). Moderate correlations were observed between hydration capacity and ash (\(r=-0.46\), \(p<0.05\)), fat contents (\(r=-0.48\), \(p<0.05\)) and foaming capacity (\(r=-0.50\), \(p<0.05\)). Swelling power was positively correlated with foaming capacity (\(r=0.44\)), fat  
Figure 3: Principal Component Analysis (PCA) bi-plot: CW—Control white sorghum, CR—control red sorghum, T1—dry heat treatment at 121 \({}^{\circ}\)C, T2—dry heat treatment at 140 \({}^{\circ}\)C, L/M/S—particle sizes, I—integral.  
(\(r=0.69\)), ash (\(r=0.66\)) and oil absorption capacity (\(r=0.60\)) and negatively with protein content (\(r=-0.51\)) and fibers (\(r=-0.48\)), significant at \(p<0.05\) level. Moderate correlations were obtained between solubility index and flours moisture content (\(r=0.48\), \(p<0.05\)), carbohydrates (\(r=-0.36\), \(p<0.05\)) and water retention capacity (\(r=0.45\), \(p<0.05\)). Bulk density was positively correlated with the protein content (\(r=0.45\)) and negatively with fat (\(r=-0.50\)), ash (\(r=-0.59\)) and oil absorption capacity (\(r=-0.73\)), significant at \(p<0.05\). Similar, but stronger correlations were obtained between emulsifying activity and protein content (\(r=0.64\)), fat (\(r=-0.77\)), ash (\(r=-0.80\)), oil absorption capacity (\(r=-0.84\)) and hydration capacity (\(r=0.55\)). Emulsion stability was moderately correlated with the protein content of flours (\(r=0.46\), \(p<0.05\)). Significant negative (\(p<0.05\)) correlations between carbohydrates and moisture (\(r=-0.63\)) and carbohydrates and fibers (\(r=-0.40\)) were obtained, while fat and ash contents were positively correlated (\(r=0.69\)). The hydration capacity, swelling power and emulsifying activity were moderate correlated with fiber content (\(p<0.05\)).  
Similarities and oppositions between variables were underlined by means of Principal Component Analysis (Figure 3), 58.93% of the total variance being explained. The first component (PC1) explained 37.27% of data variation, while the second one (PC2) explained 21.66% of the variance.  
Emulsifying activity, bulk density, fiber content swelling power, fat content, oil absorption capacity, ash content, and foaming capacity were associated with PC1, while moisture content, solubility index, water retention capacity, carbohydrates content, and energetic value were associated with PC2. Emulsion stability, fiber content and hydration capacity position close to the origin underlined their smaller contribution to the data variation.  
Control samples with different particle sizes were positioned in the upper part of the graphic and were associated with water retention capacity, moisture content, solubility index, and protein content, while treated sorghum flows with different particle sizes were placed on the lower side. Treated samples with L particle size were grouped and were associated with water absorption capacity, hydration capacity, and emulsifying activity. On the other hand, treated samples with M and S particle sizes were associated with energetic value, swelling power, fat and ash contents, foaming capacity, solubility index and oil absorption capacity.