# The Effect of Pharmaceutical Excipients for Applying to Spray-Dried Omega-3 Powder
## 3 Results
### Characteristics of Omega-3 Fatty Acid Powder  
The morphology of P18-1 to P18-4 was dented sphere and they had many pores. However, P18-5 had excessively many dent with an irregular shape. There is no significant difference in morphology according to inlet temperature, outlet temperature and atomization pressure (Figure 2). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Formular**} & **Moisture** & \multirow{2}{*}{**SE (nm)**} & \multirow{2}{*}{**RE (nm)**} & **Free Oil** & **Encapsulated** & **Total Oil** \\  & **(\%)** & & & **(g/100 g)** & **Oil (g/100 g)** & **(g/100 g)** \\ \hline P18-6 & 2.03 \(\pm\) 0.15 & 355.83 \(\pm\) 21.1 & 366.80 \(\pm\) 16.51 & 32.53 \(\pm\) 2.20 & 18.55 \(\pm\) 0.67 & 52.77 \(\pm\) 0.94 \\ P18-7 & 2.33 \(\pm\) 0.06 & 354.93 \(\pm\) 6.21 & 337.37 \(\pm\) 15.46 & 30.33 \(\pm\) 0.83 & 19.14 \(\pm\) 1.07 & 51.89 \(\pm\) 0.93 \\ P18-8 & 2.43 \(\pm\) 0.15 & 328.37 \(\pm\) 19.5 & 355.97 \(\pm\) 14.28 & 29.21 \(\pm\) 0.66 & 19.38 \(\pm\) 0.81 & 52.44 \(\pm\) 1.30 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: _Cont._  
Figure 2: _Cont._P18-8 was chosen as the best formulation, which had the smallest particle size before spray drying, showed the least amount of free oil and the highest amount of encapsulated oil, and showed relatively uniform morphology without dent. The morphology of omega-3 powder was shown in Figure 3. Even though unsaturated fatty acids do not solidify and exist in liquid form at low temperatures due to the structurally unstable nature [20], the morphology of omega-3 powder differed from powder containing olive oil. Comparing with formulation P18-8, only free-extractable oil content was increased significantly at P-O formulation, and there was no significant difference on the others properties, contrastively having difference in morphology. The free-extractable oil content of P-O formulation was about 33%. And the encapsulated-oil content was approximately 18%. The droplet size was about 310 nm to 320 nm. On the other hand, there are some publications about the structural characteristics of oil powders such as sardine oil and echium oil demonstrating a loss in crystallinity [21; 22]. Taken together, P18 composed of \(\gamma\)-CD and hydrogenated lecithin was chosen for a further study. As \(\gamma\)-CD was increased, content of free oil was decreased and that of encapsulated oil was increased. In case of diluted emulsion (P18-6), the free oil content was lower than that of P18-4. The free oil content was decreased as spray-drying temperature was decreased (Table 5). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Formal** & **Moisture (\%)** & **SE (nm)** & **RE (nm)** & **Free Oil** & **Encapsulated** & **Total Oil** \\  & & & **(g/100 g)** & **Oil (g/100 g)** & **(g/100 g)** \\ \hline P-O & 2.63 \(\pm\) 0.21 & 309.37 \(\pm\) 10.17 & 326.70 \(\pm\) 9.53 & 33.46 \(\pm\) 1.22 & 18.57 \(\pm\) 0.69 & 53.29 \(\pm\) 1.50 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: The effect of the optimal spray drying condition on moisture amount, particle size and oil amount (free oil, encapsulated oil and total oil) of spray-dried omega-3 powder using \(\gamma\)-CD and hydrogenated lecithin (n = 3). Figure 3: The SEM image of spray-dried omega-3 powder using \(\gamma\)-CD and hydrogenated lecithin with the optimal spray drying condition. Figure 2: The effect of various spray drying condition on the morphology of spray-dried olive oil powder. It is interesting that as atomization pressure was reduced (P18-8), the free oil content was the least and the encapsulated oil was the most. There was no significant difference between droplet size of secondary emulsion and reconstituted emulsion of spray dried omega-3 powder. This small difference between droplet size of SE and RE suggested that emulsion maintained enough stable and dried-particle was well dispersed. The concentration of EPA and DHA was reported in Table 6. Almost of DHA was remained after spray-drying, but just 80% of EPA was maintained.