挤压膨化后微体化预处理水酶法提取大豆油脂工艺研究

Research of extruded-ultra-micro pretreatment of aqueous enzymatic extraction of soybean oil technology

在单因素实验的基础上,选取挤压温度、螺杆转速、物料含水量、模孔孔径和膨化后物料粉碎粒度5个因素为自变量,以总油提取率为响应值,进行响应面实验设计,确定了最佳提油率下的挤压-微体化参数。结果表明,挤压最佳条件为温度96℃、螺杆转速96r/min、物料含水率14.6%、模孔孔径15mm、膨化后物料粉碎粒度120目,此时提油率为94.34%±0.74%。并且采用红外光谱分析了大豆挤压膨化前后提取的大豆分离蛋白二级结构变化,进而讨论蛋白结构变化对水酶法提取油脂过程中油脂释放的影响,结果表明,挤压膨化后蛋白质二级结构中β-折叠含量降低,无规卷曲含量升高,蛋白质由有序向无序结构的转化,可以使得酶解过程中油脂释放量增加。

Based on single-factor experiments, five factors of extrusion temperature, rotatory speed, moisture, die diameter and particle size were chosen to evaluate in the present study.The response factor was oil extraction rate. By employing RSM design programmed, the optimized parameters were generated as follows： extrusion temperature 96℃, rotatory speed 96r/min, moisture 14.6%, die diameter 15mm, particle size 120mesh, and oil extraction rate 94.34% ± 0.74%.Further analysis on the profile of secondary structure of soybean was carried out by using infrared spectroscopy method. The results illustrated that the oil extraction rate increased along with decreasing β-sheet content, increasd random coil content, and transferred unordered protein to ordered protein.