连续相变萃取南瓜籽油的工艺优化及其成分分析

Extract Process Optimization and Component Analysis of Pumpkin Seed Oil by Continuous Phase Transition Extraction

为了高效萃取南瓜籽油,充分发挥其应用价值,本研究采用连续相变萃取技术(continuous phase transition extraction,CPE)提取南瓜籽油,以提取率及活性成分含量为指标,研究萃取温度、萃取时间、萃取压力、解析温度对南瓜籽油提取效果的影响,通过响应面设计确定最佳提取工艺参数,并与超临界流体萃取技术(supercritical fluid extraction,SFE)和螺旋压榨法(screw pressing,SP)对比,对南瓜籽油的提取率、活性成分含量、理化性质和脂肪酸组成进行比较分析。结果表明,CPE萃取南瓜籽油的最佳工艺参数为:萃取温度46℃、萃取时间72 min、萃取压力0.51 MPa、解析温度65℃。此工艺参数下南瓜籽油的提取率高达96.75%,比SFE和SP法分别提高14.49%和35.24%;而总酚、类胡萝卜素、甾醇、锌含量分别为1333.80 mg/kg、8.41 mg/kg、2.59 mg/g和9.61 mg/100 g,分别是SFE法的1.56、2.29、1.17、1.40倍,分别是SP法的1.54、2.56、1.89、2.46倍。CPE所得南瓜籽油为澄清透明、粘稠性的液体,风味清香,其酸价、碘值和过氧化值的理化指标均符合LS/T 3250-2017标准的要求;气相色谱-质谱法(GC-MS)分析鉴定出7种脂肪酸,其中亚油酸和油酸占总脂肪酸含量的82.32%,比SFE和SP法分别提高5.66%和8.99%。该研究表明连续相变萃取技术在兼顾南瓜籽油提取率及活性成分含量的情况下,可以有效缓解油脂氧化酸败程度、提高不饱和脂肪酸含量,为高活性南瓜籽油的工业化连续性生产提供了参考。

In order to efficiently extract pumpkin seed oil and fully realize its application value,continuous phase transition extraction(CPE)was applied to extract pumpkin seed oil in this study.The effects of extraction temperature,extraction time,extraction pressure and separation temperature on the extraction efficiency of pumpkin seed oil were studied with extraction rate and content of active ingredients as indicators.The optimum extraction process parameters were determined by response surface design.The results were compared with supercritical fluid extraction(SFE)and screw pressing(SP)methods in terms of extraction rate,active ingredient content,physicochemical properties,and fatty acid composition of pumpkin seed oil.The results showed that the optimum extraction process parameters of pumpkin seed oil by CPE were obtained as follows:Extraction temperature of 46℃,extraction time of 72 min,extraction pressure of 0.51 MPa and separation temperature of 65℃.Under these process parameters,the extraction rate of pumpkin seed oil reached 96.75%,which was 14.49%and 35.24%higher than SFE and SP,respectively.The contents of total phenols,carotenoids,sterols and zinc were 1333.80 mg/kg,8.41 mg/kg,2.59 mg/g and 9.61 mg/100 g,respectively.These values were 1.56,2.29,1.17 and 1.40 times higher than SFE,and 1.54,2.56,1.89,and 2.46 times higher than SP,respectively.The pumpkin seed oil obtained by CPE was a clarified transparent and viscous liquid,with a delicate fragrance.Its physicochemical indicators of acid value,iodine value,and peroxide value met the requirements of LS/T 3250-2017 standard.Seven kinds of fatty acids were identified by gas chromatography-mass spectrometry(GC-MS).Linoleic acid and oleic acid accounted for 82.32%of the total fatty acid content,which was 5.66%and 8.99%higher than SFE and SP,respectively.This study showed that CPE could effectively alleviate the degree of oxidative rancidity of oil and increase the content of unsaturated fatty acids while taking into account the extraction rate and active ingredient content of pumpkin seed oil,which provided a reference for the industrial continuous production of highly active pumpkin seed oil.