超临界CO2流体提取薏仁米糠油及其脂肪酸成分分析

目的确定超临界CO2提取薏仁米糠油的最佳工艺条件，分析其脂肪酸组成成分。方法用超临界CO2提取技术，提取薏仁米加工副产物糠中的油溶性成分；以提取压力、温度、时间和CO2流量4个因素，进行单因素试验和正交试验，确定最佳工艺条件。GC／MS分析最佳工艺条件下薏仁米糠油脂肪酸成分。结果超临界CO2技术提取薏仁米糠油的最佳工艺条件为：压力35MPa、温度50℃、时间4．5h和CO2流量11mL／min，最佳工艺条件下薏仁米糠油得率17．29％。薏仁米糠油鉴定19种组分，其中油酸甲酯含量最高为50．70％，亚油酸甲酯及其同分异构体超过35％，总不饱和脂肪酸含量为87．40％。结论利用超临界CO2技术提取薏仁米糠油油溶性成分，实验效果良好，油溶性成分含量较高，具有很强的实用性。

Technology for Supercritical CO2 Extraction of Pearl Barley Rice Bran Oil and Its Fatty Acid Composition Analysis

Objective To determine the optimum conditions for supercritical carbon dioxide fluid extraction （SCFE） of pearl barley rice bran oil and analyze its fatty acid composition. Methods The soluble constituents of pearl barley rice bran oil were extracted by SCFE. The effects of extraction pressure, temperature, time and CO2 flow rate on the oil yield were studied and the optimum conditions were determined by orthogonal experiments. Its constituents were analyzed by GC/MS. Results The optimum conditions were as follows： extraction pressure 35 MPa, extraction temperature 50 ~C extraction time 4.5 h and CO2 flow rate 11 ml/min. At the conditions, the oil yield was 17.29 %. GC/ MS analysis revealed 19 fatty acid compositions, and the main constituent of the oil was methyl oleate amounted to 50.70%, linoleic acid methyl ester and its isomers reached over 35 %. The content of the total unsaturated fatty acid was 87.40 %. Conclusion This study showed a good result of SCFE on the pearl barley rice bran oil extraction which contains high nutrients value, and can provide some theoretical guidance for the further development.