南极磷虾等径滚轴挤压剥壳工艺优化

该文采用响应面分析法对南极磷虾滚轴挤压剥壳工艺参数进行优化,以剥壳得肉率为试验指标，以滚轴转速、滚轴间隙、旋转圈数为自变量，在单因素试验的基础上进行响应面分析。获得最佳工艺条件为：滚轴转速1.6 r/s、滚轴间隙0.5 mm、旋转圈数1.7 r，预测的得肉率为36.44%，此参数条件下的实测平均得肉率为35.17%。在最佳工艺参数下，试验放置时间与剥壳得肉率的关系，结果表明：随着放置时间的增加，剥壳得肉率逐渐降低；手工剥壳得肉率从35.29%降至29.73%，机器剥壳得肉率从34.71%降至21.08%。机器剥壳得肉率较手工剥壳相对较低，且降幅更为明显。研究结果可为南极磷虾剥壳装备的研制提供参考。

Process optimization of roller extruder with equal diameter of antarctic krill

Antarctic krill had enormous quantity in the Southern Ocean and great value of development and utilization. However pretreatment processing such as husking of Antarctic krill was more difficult than other main economic shrimps because Antarctic krill was smaller and the fishing area was far from land. The whole machining process of Antarctic krill was finished on the ocean-going ships. The research of pretreatment technology of shrimps developed later in China. Peeling method was studied in order to get integral meat of Antarctic krill. Parameters such as body length and weight of the Antarctic krill just be caught up were measured. The sample which had a body length between 40mm to 45mm was selected and be kept fresh. The krill was peeled by manual and mechanical operation respectively and the meat yield of the sample was measured. Considering the effect of shear and rub produced by differential rotation and effect of squeeze produced by relative rotation, dual rollers were designed in constant velocity and relative rotation in order to keep the meat integrally. Taking the roller diameter 50mm as the fixed parameters in the test, the impacts of roller speed, roller gap and the number of rotation on peeling were researched. The process conditions of roller extruder of Antarctic krill were optimized by Box-Behnken center-united experiment design. Taking meat yield as dependent variable, the models were obtained by using response surface analysis of the three factors of roller speed, roller gap and the number of rotations based on single factor experiments. The results indicated that interaction effect of roller speed and roller gap on the meat yield achieved very significant level. The influencing factors had a complicated relationship with each other. Among these factors roller gap had the most significant impact on the meat yield, roller speed and the number of rotations ranked in order. The optimized technology parameters were that roller speed was 1.6 rolls per second, the roller gap was 0.5 mm and the number of rotations was 1.7r, respectively. Under the optimized conditions the meat yield was 36.44%. The experiment indicated that there was a good fit between the predicted and the experimental values. The mathematical model was also very accurate. Therefore, the peeling process conditions getting from the response surface for Antarctic krill had a certain value in use and the method would probably be used on the ship. Then the relationship between the storage time of krill and the meat yield was studied. The results showed that: the meat yield of peeling continuous decrease with the increase of storage time. The meat yield by manual husking reduced from 35.29% to 29.73% and the meat yield by machine reduced from 34.71% to 21.08%. Mechanical manipulation got lower meat yield than the manual operation and the decline was more apparent. Meat of krill might easier be squished in peeling by machine and caused the reducing of the meat yield. This phenomenon was more obviously under poor quality. The result provided the reference for the development of peeling equipment of Antarctic krill.