水酶法提取山核桃油脂工艺研究

Study on the Extraction Technology of Walnut Oil by Aqueous Enzymatic Method

为优化水酶法提取山核桃油脂工艺,以山核桃为原料,采用水酶法提取油脂,在单因素试验基础上,采用响应面法研究木瓜蛋白酶用量、酶解时间、pH值、酶解温度和料液比对山核桃油提取率的影响;采用气相色谱-质谱联用技术分析提取油脂的脂肪酸组成,并对比了压榨法、溶剂法和水酶法3种方式对油脂理化性质的影响。结果表明,水酶法提取山核桃油脂工艺的最佳条件为:木瓜蛋白酶量0.17%,酶解时间150 min,pH值6.34,酶解温度54.43℃、料液比1∶5,在此条件下山核桃中油脂提取率为81.32%。采用气相色谱-质谱联用技术对提取油脂的脂肪酸组成进行分析,共测出12种脂肪酸,棕榈酸、油酸、亚油酸、亚麻酸是4种主要脂肪酸,其中饱和脂肪酸(SFA)占7.61%,单不饱和脂肪酸(MUFA)占69.10%,多不饱和脂肪酸(PUFA)占23.29%。对比3种提油方式发现,水酶法是一种较为理想的油脂提取方法。本研究结果为水酶法提取山核桃油脂生产提供了理论依据。

In order to optimize the aqueous enzymatic extraction of walnut（ Caryacathayensis Sarg.） oil. The extraction process of walnut oil was studied by using aqueous enzymatic method. The single factor experiments and response surface were conducted for analysis of papain concentration,enzymatic time,pH value,enzymatic hydrdysis temperature and liquid-to-solid ratio on the extraction rate of walnut oil. The fatty acid compositions of the walnut oil were analyzed by GC-MS and the physicochemical properties of walnut oil extracted with pressing method,solvent extracting and aqueous enzymatic methods were determined and compared. Results showed that the optimum technological condition for walnut：enzyme concentration was 0. 17%,enzyme reaction time was 150 min,pH value 6. 34,extraction temperature was54. 43℃ and liquid-to-solid ratio was 1： 5 by analysis of response surface method. Under this condition the extraction ratio of walnut oil was 81. 32%. Twelve fatty acids were found in walnut oil by GC-MS,The palmitic acid,oleicacid,inoleic acid and linoleic acid were the four main ingredients,the content of saturated fatty acid（ SFA）,monounsaturated fatty acid（ MUFA） and polyunsaturated fatty acid（ PUFA） were 7. 61%,69. 10% and 23. 29%, respectively.Comparison of three methods for oil extraction,aqueous enzymatic method was the ideal extraction of oil. This research provided theoretical basis for oil extraction by using aqueous enzymatic method.