Extraction And Separation Of Oil And Other Components In The Euphausia Superba

Euphausia superba is a kind of crustacean zooplankton which lives in the water area of Antarctica. Phospholipids and polyunsaturated fatty acids are rich in antactic krill oil grease which is accounted for about15%of krill’s dry weight. It is a hot area of research for its high biological functions. At present, all methods used in Euphausia superba oil extraction need drying to get rid of water. This process consumes a lot of energy, and may undermine the quality of oil grease at high temperature. In addition, those methods only consider of the oil grease extraction, just lose sight of other bioactive substances in Euphausia superba, resulting in a great deal of waste. Considering of the comprehensive utilization of Euphausia superba, the oil grease extraction and the salting-out extraction of the biologically active substances from Euphausia superba were well combined in this research.On the one hand, frozen shrimp of Euphausia superba was taken for example to investigate the effect of the mixed solvent of hexane and ethanol on the extraction of oil grease at low temperatures. The results showed that, under the conditions of the mass ratio of hexane and ethanol of10:1, the solid-liquid ratio of shrimp and solvent of1:5, stirring speed of150rpm, strring time of120min, the best effect of extraction was achieved. And the yield of the Antarctic oil grease was2.78%. In this crude Antarctic oil grease, the phospholipid content was29.13%, the acid value28.35mg KOH/g, the iodine value103.9g/100g, the saponification value165.05mg KOH/g oil, and the moisture and volatile matter content0.56%. Fatty acids composition analysis showed that the content of unsaturated fatty acids was high.On the other hand, the residues of oil grease extraction were taken for example to investigate the effect of the three-liquid-phase system of hexane/ethanol/sodium carbonate on the extraction of the Euphausia superba bioactive substances. The results showed that, at the conditions of hexane30%(w/w)/ethanol21%(w/w)/sodium carbonate16%(w/w), and the temperature of37℃,90.15%content of oil grease and38.6%content of astaxanthin were distributed in the top phase,42.9%content of astaxanthin was distributed in the middle phase, most of the shrimp flesh and shrimp shell allocated in the solid phase between the middle and the bottom phase, the bottom phase was salt solution that can be recycled.The total yield of of the Antarctic oil grease was97.8%.