Abstract: In order to optimize the expansion processing parameters  of floating aquatic fodder, the evaluation indexes of fodder processing quality were calculated by expansion ratio, bulk density, water absorption and dissolution rate. The response surface analysis method was used to study the effects of screw speed, output barrel temperature and material moisture content on fodder processing quality. The microscopic morphology of the fodder was observed by scanning electron microscopy. The results showed that: moderate screw speed, output barrel temperature and low material moisture content were conducive to the formation of a higher fodder expansion degree. The higher screw speed and output barrel temperature were conducive to the formation of a lower fodder bulk density, water absorption and dissolution rate. The optimized expansion parameters for the floating aquatic fodder were 130 r·min^-1 screw speed, 150 ℃ output barrel temperature and 10% material moisture content with 1.223 expansion ratio, 0.398 g·mL^-1 bulk density, 214.803% water absorption and 4.297% dissolution rate. The microscopic surface of the optimized floating aquatic fodder was relatively smooth and round, the melting effect of the material was good, the fodder structure was dense, and the comprehensive quality of the fodder was better.

Key words: floating aquatic fodder, expansion process, expansion ratio, bulk density, water absorption, dissolution ratio

摘要： 为优化浮性水产饲料挤压膨化加工参数，以膨化度、容积密度、吸水性和溶失率作为饲料加工品质评价指标，采用响应面分析法研究了螺杆转速、出料段机筒温度和物料含水率对饲料加工品质的影响，并利用扫面电镜观测了饲料微观形貌。结果表明：适中的螺杆转速、出料段机筒温度以及低物料含水率，有利于形成较高的饲料膨化度；高螺杆转速与高出料段机筒温度有利于形成较低的饲料容积密度、吸水性以及溶失率；优化后的浮性水产饲料膨化加工参数为螺杆转速130 r·min^-1，出料段机筒温度150 ℃，物料含水率10%，其加工后的饲料膨化度、容积密度、吸水性和溶失率分别为1.223、0.398 g·mL^-1、214.803%、4.297%；优化后的浮性水产饲料微观表面相对光滑圆润，物料的熔融效果较好，结构质密，饲料膨化加工综合质量较好。

关键词: 浮性水产饲料, 膨化加工, 膨化度, 容积密度, 吸水性, 溶失率