微波萃取核桃油工艺

用Mars5微波萃取系统,对微波萃取山核桃仁油的影响因素,包括溶剂类型、提取温度、提取时间、萃取溶剂体积进行单因素的考察。实验结果表明,正己烷是萃取核桃仁油的较佳溶剂,在单因素的试验基础上通过正交实验设计得出优化的微波萃取核桃仁油的工艺条件:提取温度为60℃,提取时间为12min,每克核桃仁用萃取溶剂7mL。将萃取方法进行了比较。结果表明,微波萃取时间明显的缩短(是磁力搅拌法的1/12、索氏提取法的1/20),萃取温度也比传统方法下降5℃,微波萃取法所用溶剂体积较磁力搅拌法低,而且提油率也比传统方法高。利用气相色谱分析核桃油中的脂肪酸的组成,微波萃取法得到的核桃仁油与传统方法相比在脂肪酸组成上有了明显的变化,其中不饱和脂肪酸的质量分数由82.94%上升到90.25%,而亚油酸的质量分数由43.49%上升到48.23%。

Process of Walnut Oil by Microwave Extraction

The conditions of microwave extracting walnut oil were discussed by using the Mars5 microwave extraction system, including solvent, microwave extraction temperature, extraction time and the volume of extraction solvent. According to the results of single fraction experiments, the optimized conditions of microwave extracting walnut oil were obtained by orthogonal experiments: extraction temperature is 60 ℃, extraction time is 12 minutes, 7 mL the liquid volume per gram walnut. Compared with Soxhlet method and magnetic stirring extraction method, the results show that the time is shorten obviously(1/12 of the time of magnetic mix round extraction, 1/20 of time of Soxhlet method), the extracting temperature is 5 ℃ lower than that of conventional method. The consumption of solvent is less than magnetic mix round extraction and the oil yield is higher than that of conventional method. Composition of fatty acid was analyzed in walnut oil by GC. There are obvious differences of composition of fatty acid between the microwave extraction oil and the conventional extraction oil. The mass fraction of the unsaturated fatty acid is increased from 82.94% to 90.25%, while the mass fraction of linoleic acid is increased from 43.49% to 48.23%.