Extrusion of Antarctic krill (Euphausia superba) meal and its effect on oil extraction

Abstract

Summary Antarctic krill meal as well as mixed krill meal and starches were extruded through a twin‐screw extruder. The extrudates were hard and porous agglomerates. The pellets still showed intact structure without obvious disintegration in response to hexane extraction. The oil recovery rates for raw krill meal and the extrudate of single krill meal were 55.08% and 59.08%, respectively. For extrudates, oil recovery rate increased along with the increasing additive amount of starches, with a maximum of 83.13%. Oil extracted from raw krill meal contained 49.30% of triglycerides (TG), 44.16% of phospholipids (PL), 1.45% of free fatty acids (FFA) and 4.69% of cholesterols (CHO). Meanwhile, polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA) and saturated fatty acids (SFA) account for 20.89%, 37.84% and 41.27% of the total fatty acids, respectively. By contrast, oils extracted from extrudates contained more TG but less PL and more SFA but less PUFA.

Antarctic Krill (Euphausia superba) Oil: A Comprehensive Review of Chemical Composition, Extraction Technologies, Health Benefits, and Current Applications

“…The contents of the different lipid classes in krill oil are influenced by many factors, such as seasonal variation, interannual environmental changes, capture stations, and sexual maturity of krill samples (Fricke, Gercken, Schreiber, & Oehlenschläger, 1984;Kołakowska, 1991;Phleger et al, 2002). In addition, the storage conditions, transportation process, and pretreatment method of raw material also have influences on the lipid composition of krill oil extracted (Sun et al, 2017a;Tilseth & Høstmark, 2015;Yin et al, 2015). For example, dehydration of krill with hot air would result in a higher FFA content compared to freeze-drying due to the lipid hydrolysis at high temperature (Sun et al, 2017a).…”

“…A similarly high lipid yield can be obtained by a one-step strategy with a mixture of acetone and ethanol (1:1, v/v) (Gigliotti et al, 2011), and the procedure is simpler than that of the two-step extraction. In addition, solvent extraction combined with the extrusion pretreatment of krill meal can improve the lipid extraction efficiency (Yin et al, 2015). The defatted krill material or krill meal still can be used as a good resource of also recovering proteins using isoelectric solubilization/precipitation (Chen, Tou, & Jaczynski, 2009), or producing peptides or target amino acids by enzymatic hydrolysis (Wang et al, 2016;Zhao, Yin, Liu, & Cao, 2013) or fermentation technology (Sun & Mao, 2016) for human consumption.…”

Influence of Storage Conditions on the Stability of Phospholipids-Rich Krill (Euphausia superba) Oil

“…Lipid class composition was determined by using the Iatroscan MK-6S thin layer chromatography-flame ionization detection (TLC-FID) Analyzer (Iatron Inc., Tokyo, Japan), according to the procedure described in our previous study (Yin et al 2015). Briefly, 1 lL of lipid sample (10-20 mg/mL in chloroform) was spotted onto silica-coated quartz rods (SIII Chromarods, Iatron Inc., Tokyo, Japan), and the elution was performed with n-heptane/diethyl ether/formic acid (v/v/v, 42:28:0.3).…”

“…Fatty acid composition was analyzed according to a procedure described in our previous study (Yin et al 2015). Briefly, 100 mg of lipid sample was transferred into a Teflonlined screw-capped vial containing 2.5 mL of 500 g/L KOH and 5 mL of 95% ethanol.…”

Food research from China: a special issue for IJFST

“…few years. Many of these recent publications have been heavily cited such as work on fish utilisation Ge et al, 2015), new functional food ingredients Wang et al, 2015;Wu et al, 2015), wine science Jiang et al, 2015;Lu et al, 2015), cereal technology (Ding et al, 2015;Zhao et al, 2015) and novel food processing techniques (Ban et al, 2015;Huang et al, 2015;Liu et al, 2015;Yin et al, 2015;Zhang et al, 2015). Research has also focussed on the role of food materials in human health such as tea consumption , dairy products (Bi et al, 2015;Tian et al, 2015) and antioxidants from a wide range of sources Dong et al, 2015;He et al, 2015).…”