挤压加工对谷物早餐粉膳食纤维成分和物理性质的影响

Effect of extrusion processing on physical properties and functional ingredients of high fiber cereal breakfast powder

以粳米和赤小豆为原料，添加枣渣及红莲，用挤压法生产高膳食纤维谷物早餐粉，采用响应面分析法研究加工参数对挤压产品膳食纤维成分和物理性质的影响。结果发现，中等螺杆转速（100r／min）、中等末区温度（130～140℃）和低进料水分含量（20％），有利于产品中不溶性膳食纤维向可溶性膳食纤维转化；低进料水分含量和中等末区温度有利于膨化度的提高；升高温度有利于吸水性指数和水溶性指数的提高，提高螺杆转速会增加水溶性指数，降低吸水性指数。最适加工参数确定为：进料水分含量20％，末区温度130℃，螺杆转速100r／min，进料速率1．0r／s。

Extrusion technology was used to processing the cereal breakfast powder rich in dietary fiber from rice, red bean, red lotus seeds and jujube residue. Response surface analysis theory was used to study the influence of processing variables on the physical and functional ingredients of extruded products. The results showed that processing conditions with moderate screw speed （100 r/min） and temperature （130 - 140 ℃ ） and low feed moisture content （20 %） was benefit to the conversion of soluble dietary fiber to insoluble diet- ary fiber. And expansion ratio was higher at moderate temperature and lower feed moisture content. Rising temperature would increase water absorption index and water solubility index both. While increasing screw speed would increase water solubility index and reduced water absorption index. And the optimum processing conditions were determined： feed moisture content 20%, the end zone temperature 130 ℃, screw speed 100 r/min, feeding rate 1.0 r/s.