本研究運用超臨界二氧化碳進行印加果精油的萃取，探討壓力、溫度對精油產率的影響。在實驗規劃中運用中央合成設計法( CDC )，對二階反應曲面( RSM )模型進行迴歸。因 CDC 必須考慮到軸點，故每組實驗條件因子具有五種水準。實驗設計的壓力條件為3600 psi、4000 psi、5000 psi、6000 psi及6400 psi；溫度條件為41 ℃、43 ℃、48 ℃、53 ℃及55 ℃。
本次實驗為二因子的中央合成設計，故有4個角點、4個軸點及5個中央點，共13組實驗。對實驗結果運用 SPSS 及 Excel 進行二階迴歸分析與變異數分析，再使用 MATLAB 將數據繪製成反應曲面圖與等高線圖。最後觀察各項因子間交互作用的顯著性以得到最佳之萃取條件。本試驗結果實驗條件於6400 psi、48 ℃，會有最大產率41.43 %，得出壓力為產率最大變因。
最後利用氣相層析火焰離子偵測器( GC-FID )分析不同實驗條件下的的超臨界流體萃取物，確認印加果精油中的不飽和脂肪酸的成分，得到的結果為 ALA 約佔所有脂肪酸含量的45 %，但未偵測到 DHA，另外，利用冷壓法對印加果精油進行分析，結果表明，冷壓法與超臨界二氧化碳所萃取之印加果精油成分類似。
In this study, supercritical carbon dioxide was used to extract the essential oil of Plukenetia Volubilis, and to investigate the influence of pressure and temperature on the yield of essential oils . The central composite design ( CDC ) method was used to regress the second-order response surface methodology ( RSM ) model in the experimental planning. Because the pivot point must be considered in the CDC , experiment condition factor for each experiment was designed as five control gruops which are 3600 psi / 41℃, 4000 psi / 43 ℃, 5000 psi / 48℃, 6000 psi / 53 ℃, and 6400 psi / 55 ℃.
In this experiment, 13 sets of experiments were designed according to the requirements of the two-factor central composite design, including 4 corner points, 4 axis points and 5 central points. The experimental results use SPSS and Excel for second-order regression analysis and variance analysis, then use MATLAB to plot the data into RSM diagram and topographic map. In the end, observing the significance of the interaction between the various factors helps get the best extraction conditions. It’s showed that the maximum yield of 41.43 % can be founded under the experimental conditions of 6400 psi and 48 °C.
Finally, gas chromatography-flame ionization detector ( GC-FID ) was used to analyze the supercritical fluid extracts under different experimental conditionsto and confirm the composition of unsaturated fatty acids in the essential oil of inca fruit. The result is that ALA is account for being cloles to 45 % in all fatty acids of the content, but DHA were not detected. In addition, the cold expression method was used to analyze the essential oil of Plukenetia Volubilis. The study show that the results of the cold expression method and supercritical carbon dioxide are similar.
