The objective of this work was to evaluate the effects of drying, grinder type, and moistening conditions on the interparticle porosity of feed material and the torque supplied to the screw during the single-screw extrusion processing of brown rice. The grains were dried at 60 °C up to moisture contents of 9 and 6% and then milled using two grinder types (disc and roller). The milled products were moistened at levels to produce extruded snacks (11 and 14%). Irrespective of drying the grains, lower particle diameters in the fine and coarse fractions, and narrower distributions were obtained by grinding brown rice in a roller mill than in a disc mill. The disc mill products presented lower interparticle porosity and generated higher torque values than the roller mill products. A reduction in grain moisture from 9 to 6% only decreased the interparticle porosity of disc mill products and increased the torque. An increase in feed moisture from 11 to 14% only increased the interparticle porosity of roller mill products and decreased the torque regardless of grain moisture. This work contributed to understanding the impact of the morphology of the particles in the torque variability during the extrusion processing of brown rice. Few published works correlate physical properties of the feed material with extrusion dependent variables. In the present study, feed materials with high interparticle porosity were produced with roller mill and when extruded they generated low variabilities in the torque.

中文翻译：

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谷物预处理对糙米挤压过程中进料颗粒间孔隙率和扭矩的影响

这项工作的目的是评估干燥，粉碎机类型和加湿条件对糙米的单螺杆挤出加工过程中进料的颗粒间孔隙率和提供给螺杆的扭矩的影响。将谷物在60°C下干燥至水分含量分别为9和6％，然后使用两种研磨机（盘式和辊式）进行研磨。将研磨后的产品润湿一定的水平，以生产膨化小吃（11％和14％）。与将谷物碾碎相比，与辊式碾碎机相比，在辊式碾碎机中碾磨糙米可获得细小和粗粒级的较低粒径，并且分布较窄。盘式粉碎机产品比辊式粉碎机产品具有更低的颗粒间孔隙率和更高的扭矩值。谷物水分从9％降至6％只会降低圆盘磨机产品的颗粒间孔隙率，并增加扭矩。进料水分从11％增加到14％只会增加辊磨产品的颗粒间孔隙率，并降低扭矩，而与谷物水分无关。这项工作有助于理解糙米在挤压过程中颗粒形态对扭矩变化的影响。很少有发表的著作将饲料原料的物理性质与挤出相关变量相关联。在本研究中，使用辊磨机生产出具有高颗粒间孔隙率的进料，并且在挤压时它们产生的扭矩变化很小。进料水分从11％增加到14％只会增加辊磨产品的颗粒间孔隙率，并降低扭矩，而与谷物水分无关。这项工作有助于理解糙米在挤压过程中颗粒形态对扭矩变化的影响。很少有发表的著作将饲料原料的物理性质与挤出相关变量相关联。在本研究中，使用辊磨机生产出具有高颗粒间孔隙率的进料，并且在挤压时它们产生的扭矩变化很小。进料水分从11％增加到14％只会增加辊磨产品的颗粒间孔隙率，并降低扭矩，而与谷物水分无关。这项工作有助于理解糙米在挤压过程中颗粒形态对扭矩变化的影响。很少有发表的著作将饲料原料的物理性质与挤出相关变量相关联。在本研究中，使用辊磨机生产出具有高颗粒间孔隙率的进料，并且在挤压时它们产生的扭矩变化很小。很少有发表的著作将饲料原料的物理性质与挤出相关变量相关联。在本研究中，使用辊磨机生产具有高颗粒间孔隙率的进料，并且在挤压时产生的扭矩变化很小。很少有发表的著作将饲料原料的物理性质与挤出相关变量相关联。在本研究中，使用辊磨机生产出具有高颗粒间孔隙率的进料，并且在挤压时它们产生的扭矩变化很小。