Extraction Technology And Analysis On Lipids And Astaxanthin Of Euphausia Pacifica Hansen

Euphausia Pacifica Hansen belongs to Arthropoda，Crustacea, which is one ofthe dominant crustaceans species in North Pacific subarctic region and is widelydistributed in the Far East waters, Yellow Sea and the Taiwan Strait. EuphausiaPacifica Hansen as a kind of large zooplankton is important pelagic fish baits in themarine ecosystem. In recent years, the quantity of Euphausia Pacifica Hansenresources being in the end of the food chain is increasing largely and large due to theoverfishing of pelagic fishery resources. The present research on Euphausia PacificaHansen at home and abroad is mainly concentrated on its distribution, morphologyand ecology, while its nutrition, comprehensive processing and high-valued utilizationare less reported. It is estimated that the total amount of the resources can be tenmillion tons or so offshore china. In fact, like Euphausia superba, Euphausia PacificaHansen is rich in high quality protein, lipid and other active substances. So it’s ofgreat economic value and social significance to comprehensive process and utilizesuch large amount of low value marine aquatic resources as quickly as possible. Inthis thesis, we firstly analyzed and evaluated the basic nutritional compositionts ofEuphausia Pacifica Hansen, and then the deep and comprehensive research onprocessing and utilization of the lipids which are rich in polyunsaturated fatty acid andthe astaxanthin were carried out. We hope that our research will lay a foundation forfurther studies on the Euphausia Pacifica Hansen.The contents and results of this study are mainly described as follows:1. Conventional methods were used to comprehensively detect and evaluate thenutritional value of Euphausia Pacifica Hansen in proteins, lipids, ash, minerals andtrace elements and other nutrients. The content of protein in the whole shrimp was65.80±2.6%. The content of total fat extracted by Folch method was15.16±0.8%. Thecontent of ash was12.40±0.9%. The content of nitrogen free extract was12.83±0.4%.In proteins,56.5%of which was total amino acids, including26.01%eight kinds ofessential amino acids. In lipids, unsaturated fatty acid content accounted for55.54%in total fat,23.36%of which was EPA and DHA. Euphausia Pacifica Hansen also hadrich and complete content of minerals and trace elements. By comparing withEuphausia superba and Fenneropenaeus Chinensiss, Euphausia Pacifica Hansen wasof very high nutritional and exploitable value. 2. Using the entire Euphausia Pacifica Hansen powder as the raw material,neutral lipids were extracted by n-Hexane. Results of single factor experiment andorthogonal experiment showed the optimal conditions of the extraction process wereextraction temperature being60℃, the liquid-solid ratio6:1and extraction time2h.Under these conditions, the maximum neutral lipids yield was10.47±1.12%, but thecholesterol content was3.39%. In order to obtain higher quality neutral lipids withlow content of cholesterol, β-cyclodextrin was used to remove the cholesterol. Whenthe β-cyclodextrin addition content is0.4gram per gram of lipids, bathingtemperature was60℃，mixing time was30min, the cholesterol reduction rate was74%and the cholesterol content in neutral lipids was reduced from3.39%to0.88%.The EPA and DHA content was20.9%measured by GC-MS.3. After n-hexane extraction, krill powder was used to extract polar lipids usingethanol. Results of single factor experiment and orthogonal experiment showed theoptimal extraction conditions were extraction temperature being50℃, the liquid-solidratio8:1, the extraction time4h, under which the maximum crude polar lipids yieldwas13.21±1.15%. The phospholipids content obtained was82.41%measured bysilica gel column chromatography detection. The polar lipids’ EPA+DHA contentwere up to29.3%measured by GC-MS detection.4. Spectrophotometric detection and HPLC were used to measure totalcarotenoid content and compositions of Euphausia Pacifica Hansen, then a new greenextraction technique subcritical fluid R134a was used to the extraction of astaxanthinin the Euphausia Pacifica Hansen powder. Results showed that the content of totalcarotenoid was138.82±3.22μg/g of dry powder, the astaxanthin esters accounted for57.97%, the free astaxanthin accounted for7.34%, so the total astaxanthin was65.31%. Optimum conditions were obtained by single factor experiment and responsesurface optimization at11.18MPa,29.89℃and43.81min. Under these conditions,crude pigment oil yield was7.31%and astaxanthin recovery was up to76.94%Combining n-Hexane extracting process and elimination of cholesterol usingβ-cyclodextrin technique, neutral lipids were obtained with a good fluidity and lowcholesterol content. After n-hexane extraction, the rest krill powder was used toextract polar lipids which were rich of phospholipids using ethanol. Therefore,subcritical fluid R134a was used and optimized to extract astaxanthin in theEuphausia Pacifica Hansen powder. In conclusion, extraction technology on lipidsand astaxanthin from Euphausia Pacifica Hansen was rarely reported at home and abroad, this study could provide basic information and reference to high-value andcomprehensive utilization on Euphausia Pacifica Hansen.