## 3 Results and Discussions
### Optimization of Response  
Final polynomial equations were obtained for the effect of BS% flux and particle size (Equation (5)) and the constituent was constrained with lower and upper limits. The 3 components in real scale amounted to 100% (1% to 5% for ACM, 3% to 10% for oil, and 85% to 96% for water), respectively listed in the design. The numerical optimization of an O/W-type nanoemulsion formulation was carried out according to the desirability function using the Design-Expert (Stat-Ease Inc., Minneapolis, MN, USA, version 10.0.7) statistical software. The research objective was to evaluate how the physicochemical properties of ACM affect its efficacy as an emulsifier in sunflower O/W-type nanoemulsion using ultrasonication to optimize the emulsion formation to provide the food-grade, cosmetics, drug delivery, and personal care industry with a low cost, eco-friendly alternative emulsifier. Desirability functions were chosen to either maximize BS% flux (\(\gamma_{1}\)) and minimize Sauter mean diameter (\(\gamma_{2}\)) or maximize BS% flux (\(\gamma_{1}\)) and maximize Sauter mean diameter (\(\gamma_{2}\)). This desirability function was set to answer sub-research objective questions on whether maximizing BS% flux (\(\gamma_{1}\)) and minimizing Sauter mean diameter (\(\gamma_{2}\)) or maximizing BS% flux (\(\gamma_{1}\)) and maximizing Sauter mean diameter (\(\gamma_{2}\)) would affect the desirability options. The sub-research objective questions were also set to enable choices to be made for suitable mixture constituents' composition to fulfil emulsifier roles in the cosmetics, drug delivery, and personal care industry. Diverse nanoemulsion solutions representing different combinations of mixture constituents and independent variable levels were found by using the Design-Expert statistical software. These solutions were dependent on the degree to which the dependent variables BS flux (\(\gamma_{1}\)) and Sauter mean diameter (\(\gamma_{2}\)) were minimized and maximized. The overall desirability of the chosen formulation for option A (EOR 4.2:3) which involved maximizing BS% flux (\(\gamma_{1}\)) and minimizing Sauter mean diameter (\(\gamma_{2}\)) was 100%, which means that this formulation substantially satisfied the targeted constraints. Similarly, the overall desirability of the chosen formulation for option B (EOR 5:10) which involved maximizing BS flux (\(\gamma_{1}\)) and maximizing Sauter mean diameter (\(\gamma_{2}\)) was 95%, which means that this formulation substantially satisfied the targeted constraints. Authors have reported that O/W emulsions stabilized with octenyl succinic anhydride (OSA) starch having OSA starch concentration above 10% had drastically reduced creaming index values and stated that this  
Figure 2: Parity plot of predicted and experimental values of Sauter mean diameter of ACM O/W-type stabilized nanoemulsion. was due to network structure formation through inter-molecular bonding of OSA starch molecules [49; 50]. Hence, the structure formed increased the viscosity of the continuous phase, slowed down oil droplet movement, and reduced the rate of creaming, which means that increase in OSA starch concentration led to an increase in the physical stability of the investigated emulsions [49; 50]. The authors concluded that an increase in the concentration of oil in emulsions stabilized by OSA starch caused a significant delay of creaming [49; 50]. Furthermore, the authors also reported that as oil concentration increased from 5% to 60% the apparent viscosity of the stabilized emulsions increased [49; 50]. Similarly, the authors of [49; 50] investigated the effect of oil concentration (10-50%) on the rheological, structural, and microstructural properties of ethanol-induced whey protein stabilized soy-bean oil emulsions: the authors observed that stabilized emulsions with higher oil concentration exhibited a higher degree of shear-thinning as the apparent shear viscosity decreased with increasing shear rate.