挤压膨化对豆渣可溶性膳食纤维的影响

Effect of Extrusion on Properties of Soluble Dietary Fiber from Soybean Meal

以豆渣为原料,采用挤压膨化法对豆渣可溶性膳食纤维(soluble dietary fiber,SDF)进行研究。通过预实验,确定加入质量分数为20%的淀粉膨润剂。以挤压前后豆渣SDF的增量作为评定指标,研究豆渣含水率、物料温度及螺杆转速对豆渣SDF增加率的影响。结果表明:采用挤压膨化处理后,豆渣中戊糖较己糖、糖醛酸增幅大。通过正交试验,对工艺参数进行优化,结果表明:当含水率17%、螺杆转速150r/min、温度180℃时,SDF增加率可达到199.64%。此时,豆渣膳食纤维持水力为1430%、溶胀力为16.7mL/g,分别比豆渣原料提高了94%和125%。

In order to maximize the incremental rate of soluble dietary fiber（SDF）in soybean meal after extrusion,single factor and orthogonal array design methods were employed to optimize extrusion conditions.Starch added at a level of 20%was found to be the best swelling agent.After extrusion,pentose content in soybean meal displayed a larger increase than the contents of hexose and alduronic.The optimal extrusion conditions were material moisture content of 17%,screw speed of 150 r/min and temperature of 180℃.Under such conditions,the incremental rate of SDF was 199.64%,and the water holding capacity and swelling capacity of extruded soybean meal were 1430%and 16.7 mL/g,respectively,which were 94%and 125%higher than unextruded soybean meal.