## 3 Results and Discussion
### Color Measurement  
The color of spray-dried powders can be influenced by their structure, packing density, color of individual carrier components, and processing conditions, e.g., overheating during the spray drying process or long residence times in the drying chamber [27]. The color of spray-dried powders can be also affected by the type and content of coating materials [58]. Table 5 shows the main color parameters of the obtained powders. In general, the L* value corresponds to the lightness in the range from black (0) to white (100), the positive a* value refers to a red color, and a positive b* value indicates to yellow coloration of the powder. All results are average values of 5 measurements with standard deviation. The values of the L*, a*, and b* parameters of all samples, both with the addition of 20% and 30% oils, differ significantly from the control sample (\(p<0.05\)) (only for the powder with the addition of 20% pumpkin oil, there are no significant differences in the parameter a*, compared to the reference sample (\(p>0.05\)). The control sample was the brightest. Regardless of the type and concentration of oil, the powders were relatively light (L* values in a range from 76 to 89). Powders with higher oil content were observed to be lighter (L* value) in color (except for pumpkin oil) towards a shade of green (a* value) (except for nigella oil). No significant influence of the oil type and their concentration on the b* value was observed. [PERSON] et al. [59] had microencapsulated probiotic _Enterococcus_ strains using whey protein and maltodextrin as an encapsulating matrix. They obtained L* values of 70.0 \(\pm\) 0.2, 71.3 \(\pm\) 0.5, and 70.6 \(\pm\) 0.5 for different bacterial strains. All samples were characterized by a \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Type of Oil**} & \multicolumn{2}{c}{**L*} & \multicolumn{2}{c}{**a*} & \multicolumn{2}{c}{**b*} & \multicolumn{2}{c}{**\(\Delta\)E**} \\ \cline{2-7}  & 20\% ** & 30\% ** & 20\% ** & 30\% ** & 20\% ** & 30\% ** & 30\% ** \\ \hline Reference sample & 89.64 \(\pm\) 0.01 a & \multicolumn{2}{c}{0.26 \(\pm\) 0.01 a} & \multicolumn{2}{c}{13.70 \(\pm\) 0.01 a} & \multicolumn{2}{c}{20\% **} & \multicolumn{2}{c}{30\% **} \\ \hline Milk thistle & 88.35 b  & 87.36 b  & 0.85 b  & 0.54 \(\pm\) 0.01 b  & 14.56 b  & 13.70 \(\pm\) 0.01 a  & 1.20 & 1.49 \\ \hline Pumpkin & 86.82 c  & 87.26 c  & 0.24 \(\pm\) 0.01 a  & 0.07 c  & 12.08 c  & 14.03 b  & 2.07 & 1.55 \\ \hline Cedar tree & 89.31 d  & 86.62 d  & 0.79 c  & 0.63 d  & 12.02 d  & 12.92 c  & 1.31 & 2.05 \\ \hline Nigella & 87.08 e  & 86.38 e  & 0.50 \(\pm\) 0.01 d  & 0.57 e  & 13.73 e  & 13.20 \(\pm\) 0.01 d  & 1.66 & 2.14 \\ \hline Hemp & 88.96 f  & 82.63 f  & 0.82 e  & 0.13 \(\pm\) 0.01 f  & 13.02 f  & 13.36 \(\pm\) 0.01 e  & 0.95 & 4.57 \\ \hline Storage & 88.53 g  & 75.61 g  & 0.75 \(\pm\) 0.01 f  & 12.46 g  & 11.13 f  & 1.24 & 9.59 \\ \hline \hline \end{tabular}  
* The values presented are the average of three determinations \(\pm\) standard deviation. Values with different lowercase letters in the same column are significantly different at \(p<0.05\). ** oil content in relation to the dry mass of the initial dispersion. L* for the lightness from black (0) to white (100). **a* from green (–) to red (+). b* from blue (–) to yellow (+). The statistical analyses were performed using Statistic version 10 Stat56R Poland, (Krakow, Poland). \(0<\Delta\)E \(<1\) The difference is untonucleable. \(1<\Delta\)E \(<2\) The difference is only noticed by an experienced observer. \(2<\Delta\)E \(<3.5\) The difference is also noticed by an inexperienced observer. \(3.5<\Delta\)E \(<5\) The difference is clearly noticeable. \(\Delta\)E \(>5\) Gives the impression that these are two different colors.  
\end{table} 
Table 5: Effect of the type of oils and their concentrations (20 and 30% in a ratio to dry mass of starting dispersion) on color characteristics of the spray-dried powders.