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Antarctic krill is not only rich in biological resources, but also has high utilization value. As a new protein resource, Antarctic krill will get more and more attention as the offshore fishery resources dwindle. But Antarctic krill is very small and grows in the distant Antarctic seas. Krill is rich in active enzymes and tends to deteriorate. As a result, it needs to be processed quickly on board. Therefore, the fishing and processing of Antarctic krill require higher cost and have more difficulty. In the 1960s, the development of krill industry was started from abroad, and China has begun the research on krill processing technology in recent years. Some preliminary research results have been obtained in process and equipment. Krill is often used to produce shrimp meat or to extract shrimp oil. Peeling is another effective method for the utilization of Antarctic krill. Previous research has shown that roller extrusion is one of the effective methods for the peeling of Antarctic krill. There are many factors that influence the effect of peeling in actual production, such as rotation speed, extrusion distance, and roller clearance. It is also affected by the wind and waves of the sea. The wind and waves sway the ship and affect the safety of navigation. These include the impact on personnel and the impact on equipment. The influence of sway on the equipment is reflected in the change of stability and processing effect. A composite laminates peeling equipment is developed to explore the effect of waves on the peeling results of krill. The performance of the equipment under different swing conditions in the sea was analyzed. Ships would have varying degrees of lateral sway and vertical sway during the voyage. The yield rate and residual rate of shrimp shells were measured and recorded. The roller was divided into 4 areas according to the length. The completion rate of peeling in different regions was analyzed. The experimental results show that the swing of the ship affects the yield rate and the residual rate of the shell. But the difference is not significant. Krill shell residue ratio rises to 1.07% when the longitudinal swing reaches 7°. And it rises to 1.64% when the lateral oscillation reaches 5°. The swing of the ship also has a certain effect on the completion rate of the peeling. The completion rate of peeling in the same area shows a decreasing trend, with the increase of swing amplitude. It is found that increasing the length of the roller can effectively alleviate the problem of the decrease of the peeling completion rate caused by the swing. The completion rate is greater than 95% when the roller length is about 1200 mm. The retention time has a great effect on the peeling effect. The completion rate of peeling of the krill that is stored for 2 h decreases significantly after being caught. And peeling completion rate reduces to 94% in the regional Ⅳ. The residual rate of shrimp shells increases correspondingly. The results can provide reference for the application and industrialization of Antarctic krill peeler. [ABSTRACT FROM AUTHOR]

The Antarctic krill is a marine organism with a large number. It has great value of development and utilization. As a new protein resource, Antarctic krill will get more and more attention since the offshore fishery resources are dwindling. Although the Antarctic krill has a high value of nutrition, it is hard to process because of its high fluorine content and strong enzyme activity. The krill has to be processed within 2 h on the ship after fishing in order to maintain its quality. Shelling is one of the effective methods to improve the quality of krill product. In previous studies peeling method was researched in order to get integral meat of Antarctic krill. Parameters such as body length and body weight of Antarctic krill that was just caught up were also measured. And we know that the peeling process conditions got from the response surface for Antarctic krill had a certain value in use and the method could be used on the ship. So the shelling prototype was developed and tested on the ship. In order to verify the krill shelling equipment and improve the production process, the research focused on the impacts of feeding rate, storage time and pre-cooling on shelling yield and residual rate, which would provide the bases for the practical production. The production process was considered carefully. Feeding speed was controlled by manpower in order to put the krill into a trough evenly. Then the krill would be pumped to the shelling machine after evenly mixing with water. The shrimp was put on the gauze for 2 min to filter the water after shelling, and then residual shells in shrimp were removed by manpower. The last processes were weighing, packaging and frozen. Test equipment unit was designed as 8 groups of rollers with reciprocating rotation. Yield was one of the most important indices for the evaluation of equipment ability, and residual rate was the other. The product quality of shrimp meat needed to be judged by sensory evaluation. The sensory evaluation team was made up of 5 seafarers who had a lot of experience of krill production on board. The comprehensive point was based on the integrity of shrimp, shell residue, plumpness and cleanliness. The results showed that the yield was about 24% and the residual rate was about 5%, and the shelling equipment was reliable. The yield of shelling from fresh Antarctic krill reduced slowly with the increasing of the feeding speed. It was relatively stable when the feeding speed was under 50 kg/h. And the residual rate was on the rise with the increasing of the feeding speed. When the feeding speed was higher than 60 kg/h, the residual rate of shrimp shell increased significantly. The krill with the storage time of less than 120 min could be used for production. Freshness is the most important factor in the quality of shrimp meat. Pre-cooling is an effective way to maintain shrimp quality. Frozen shrimp is not recommended to be used because the yield of shrimp meat will become lower significantly. [ABSTRACT FROM AUTHOR]