Effects on Components and Quality of Jujube Kernel Oil Extracted by Different Extraction Methods

Jujube seed oil was extracted from jujube seed by subcritical butane extraction,soxhlet extraction and ultrasonic assisted extraction,respectively,in order to explore the effects of different extraction methods on oil yield,content of fatty acids and the main physicochemical. Using Schaal oven method to compare the oxidation properties of jujube seed oil by different extraction method. The results showed that the oil yeild of jujube seed oil by subcritical butane extraction,soxhlet extraction and ultrasonic assisted extraction were 26.73%,28.02% and 24.45%. Moreover,these oil samples had nearly identical fatty acid composition as measured by gas chromatography-mass spectrometry,and the main fatty acid were oleic acid and linoleic acid. In addition,the content of unsaturated fatty acid is subcritical butane extraction method(74.12%)>ultrasonic extraction method(71.46%)>soxhlet extraction(69.78%).The total unsaturated fatty acid content and quality in jujube seed oil by subcritical butane extraction is significantly higher than the other two methods. The content of V_E was measured in jujube seed oil by high performance liquid chromatography,found that subcritical butane(202.71 mg/kg_oil)>soxhlet extraction(139.01 mg/kg_oil)>extracted assisted ultrasound(87.04 mg/kg_oil). Since the oxidation test extracted by the three methods of jujube seed oil,the order of peroxide value was soxhlet extraction>ultrasonic extraction>subcritical butane extraction. In conclusion,each method had its own characteristics for extraction of jujube seed oil,subcritical butane extraction had advantages with more oil yield and quality in jujube seed oil and high safety than other two methods,and therefore it would be more suitable for the extraction of jujube seed oil.