## 3 Results and Discussion
### Effect of Molecular Distillation Parameters on Deacidification Performance  
Figure 1A demonstrates the effect of evaporator temperature on AV and deacidification efficiency, revealing that an increase of this temperature from 120 to 200 \({}^{\circ}\)C decreased the AV from 0.25 to 0.10 mg KOH/g and increased deacidification efficiency from 50.93% to 79.80%, in agreement with the results of [PERSON] et al. [17]. The rapid increase of deacidification efficiency with increasing evaporation temperature was ascribed to the concomitantly increasing efficiency of volatile fatty acid removal. In theory, molecular distillation achieves separation by utilizing differences between the average free paths of molecular motion. In turn, these free paths are proportional to the evaporator temperature [25], i.e., an increase of evaporator temperature accelerates the evaporation of materials and increases the proportion of small molecules such as free fatty acids in the light phase, while the AV of heavy-phase oil decreases.  
Figure 1B shows the effects of scraper speed, revealing that an increase of this parameter from 180 to 260 rpm increased deacidification efficiency (from 62.50% to 90.28%) and decreased AV (from 0.19 to 0.05 mg KOH/g). This behavior was explained by the fact that high scraper speeds increase the uniformity of soybean oil distribution on the evaporation surface and thus facilitate evaporation, while saturation at a certain speed results in a slow AV decrease.  
The feed flow rate influences not only heat transfer but also production capacity. As shown in Figure 1C, when the feed flow rate increased from 1 to 5 mL/min, AV increased from 0.09 to 0.15 mg KOH/g, while deacidification efficiency decreased from 80.96% to 70.50%. Low feed flow rates result in prolonged residence of materials on the evaporator surface and hence, in more efficient heat transfers and increased FFA separation efficiency [26], while the reverse is true for high flow rates. Thus, low feed flow rates are required for efficient deacidification.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline  & **AV** & **PV** & **\(p\)-Anisidine** & \multicolumn{3}{c}{**Loviband Color**} & \multicolumn{3}{c}{**Tocopherol (mg/kg)**} \\  & **(mgKOH/g)** & **(meQ\({}_{\text{3}}\)/kg)** & **value** & **Yellow** & **Red** & \(\alpha\) & \(\beta\) & \(\gamma\) & \(\delta\) & **Total** \\ \hline EAE & 0.57 \(\pm\) 0.02 \({}^{\text{a}}\) & 2.98 \(\pm\) 0.04 \({}^{\text{a}}\) & 5.20 \(\pm\) 0.1 \({}^{\text{a}}\) & 5.20 \(\pm\) 0.0 \({}^{\text{b}}\) & 0.40 \(\pm\) & 147.30 \(\pm\) & 63.50 \(\pm\) & 703.20 \(\pm\) & 316.90 \(\pm\) & 1230.90 \\  & 0.6 \(\pm\) & 0.20 \({}^{\text{b}}\) & 14.10 \(\pm\) & 1.90 \(\pm\) & 24.60 \({}^{\text{a}}\) & 19.70 \(\pm\) & 13.50 \({}^{\text{a}}\) & 13.50 \({}^{\text{a}}\) & 13.50 \({}^{\text{a}}\) \\ AD & 0.27 \(\pm\) 0.04 \({}^{\text{b}}\) & 3.13 \(\pm\) 0.11 \({}^{\text{a}}\) & 5.02 \(\pm\) 0.02 \({}^{\text{b}}\) & 0.20 \(\pm\) & 14.50 \(\pm\) & 72.92 \(\pm\) & 7.50 \(\pm\) & 189.06 \(\pm\) & 32.31 \(\pm\) & 301.79 \(\pm\) \\  & & & & & & & & & & \\ \end{tabular} Note: Different letters indicate significant differences between the same groups (\(p<0.05\)).  
\end{table}
Table 1: Properties of soybean oil prepared by enzyme-assisted aqueous extraction (EAE) and conventional alkaline deacidification (AD).  
Figure 1: \(Cont\).