富含 DHA 藻油之氧化安定性及其衍生之油耗氣味成分之研究

DHA supplements is an important item of nutrimental and health business. However, the oxidation stability restricted its application. In this study, we measured the oxidation stability of DHA rich algae oil under different temperature. The derive function can be used to evaluate the shell life of DHA rich algae oil. Moreover, the volatile compounds during lipid oxidation which been considered as off-flavor are strongly related to the sensory quality of oils. We conducts solid-phase microextraction (SPME) on the head space of the container of oxidized DHA rich algae oil for adsorbing the volatile compounds. The volatile compounds were further analyzed by gas chromatography and mass spectrometry (GC/MS). The sensitivity of volatile compounds can be improved by agitation, temperature control (50 ℃ ) and appropriate adsorption time (30 minutes). Furthermore, the Carboxen®/Polydimethylsiloxane (CAR/PDMS) fiber shows better sensitivity. In conclusion, the method developed in this study for analyzing the volatile compounds of oxidized DHA rich algae oil may support the study of oil quality and sensory evaluation.二十二碳六烯酸(Docosahexaenoic acid, DHA)於近年來深受營養、保健業者所重視。然而其氧化安定性差 造成品質劣變，使得應用上有所限制。本研究在不同溫度下觀察富含 DHA 藻油的劣化，並以 Arrhenius 方程式評估 產品在不同狀況下的保存時間。油脂氧化所生成之揮發性成分為油耗味來源，其與風味劣變緊密相關。本研究以頂空 法配合固相微萃取技術(Solid-phase microextraction, SPME)進行吸附富含 DHA 藻油的氧化揮發物，並以氣相層析 質譜儀分析其組成。吸附過程中可藉由攪拌協助、調控溫度(50℃)，在適當的吸附時間(30 分)下，增加容器上部空間 的揮發物含量。結果顯示 Carboxen®/Polydimethylsiloxane (CAR/PDMS) 的纖維塗層對於油脂氧化揮發物有較佳 靈敏度。本研究開發的藻油氧化揮發物分析方法，有助於研究藻油品質並作為感官評價之佐證