不同品种玉米挤压膨化特性研究

Extrusion Properties of Corn Varieties

以黄淮海平原玉米主产区53个玉米品种为材料,以德国布拉本德食品仪器公司DSE-25型双螺杆挤压膨化实验室工作站为膨化设备,系统研究了不同玉米品种籽粒的挤压膨化特性。结果表明,在相同挤压膨化工艺条件下(水分为17%,五区温度180℃,螺杆转速120 r.m in-1,喂料速度16 r.m in-1),不同玉米品种籽粒挤压膨化物的产品特性差异较大,而挤压膨化时的系统参数差异较小。与夏玉米品种相比,春玉米品种籽粒挤压膨化物具有较高的径向膨化率、吸水性指数和产量以及较低的水溶性指数和机械能耗。玉米品种挤压膨化物的径向膨化率平均为1.53,容积密度为0.196g.mL-1,水溶性指数为38.44%、吸水性指数为430.00%,扭矩为151.33 N.m、四区压力为26.66bar、五区压力为10.77bar,产量为2.27 kg.h-1,机械能耗为841.4 W.h.kg-1。玉米籽粒的挤压膨化特性与其理化特性有关。

53 corn varieties from the Huang Huai Hai Plain, China main producing zone, were extruded using a Brabender Twin -Screw Extruder Lab -station DSE -25 with the same condition： moisture 17% , 5th zone temperature 180℃, screw speed 120rpm, and feed speed 16rpm. Extrusion properties of the corn varieties were systematical studied. The following are the results： There are great differences in product characteristics among extrudates from the corns, but little difference in system parameters. Compared with the summer corn varieties, spring corn varieties exhibit higher radial expansion ratio, higher water absorption index （WAI） , higher output, lower water solution index （WSI） and lower specific mechanical energy （SME）. The average expansion ratio, bulk density, WSI, WAI, torque, 4th zone pressure, 5th zone pressure, output and SME of the varieties are 1.53, 0. 196 g mL^-1, 38.44%, 430.00%, 151.33 N m, 26.66 bar, 108 bar, 2.27 kg h^-1, and 841.4 W h kg^-1 respectively. So, physicalchemical properties of corn varieties are correlated to extrusion properties.