Purification of Alaskan Walleye Pollock (Gadus chalcogrammus) and New Zealand Hoki (Macruronus novaezelandiae) Liver Oil Using Short Path Distillation

Abstract

The beneficial health effects of a diet rich in n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) have been extensively researched in recent years. Marine oils are an important dietary source of n-3 LC-PUFA, being especially rich in two of the most important fatty acids of this class, EPA (eicosapentaenoic acid; 20:5n-3) and DHA (docosahexaenoic acid; 22:6n-3). Oils rich in n-3 LC-PUFA are prone to oxidation that leads to loss of product quality. Alaskan pollock (Gadus chalcogrammus Pallas, 1814) and New Zealand’s hoki (Macruronus novaezelandiae Hector, 1871) are the highest volume fisheries of their respective countries. Both produce large quantities of fishery byproducts, in particular crude or unrefined n-3 LC-PUFA containing oils. Presently these oils are used as ingredients for animal feed, and only limited quantities are used as human nutritional products. The aim of this research was to investigate the applicability of short path distillation for the purification of pollock and hoki oil to produce purified human-grade fish oil to meet quality specifications. Pollock and hoki oils were subjected to short path distillation and a significant decrease in free fatty acids and lipid oxidation (peroxide and para-anisidine values) products was observed. Purified oils met the Global Organization for EPA and DHA Omega-3 (GOED) standard for edible fish oils.

Analysis of the Changes in Volatile Compound and Fatty Acid Profiles of Fish Oil in Chemical Refining Process

“…Typically, volatile components, mainly including aldehydes and ketons in fish oils may be mainly originated from the microbial spoilage and autoxidation of proteins, amino acid, and lipids. In most cases, these substances are not desirable for human consumption . Furthermore, n‐3 FAs in fish oils are exceptionally susceptible to oxidation, and the breakdown of n‐3 chain during oxidation process causes nutritional loss and detrimental sensory, with an unacceptable rancidity and fishy odor .…”

Production and concentration of monoacylglycerols rich in omega-3 polyunsaturated fatty acids by enzymatic glycerolysis and molecular distillation

“…Fregolente, Pinto, Wolf-Maciel, & Filho, 2010) or camellia oil (Zheng, Xu, Wang, Qin, Ning, Wang, et al, 2014) have been also reported. Processing of marine oils by SPD to remove pollutants and oxidation products has been reported (Oliveira & Miller, 2014;Oterhals & Berntssen, 2010), however, the studies focused on PUFA purification mainly obtained the PUFA concentrate in FFA or EE form (Breivik, Haraldsson, & Kristinsson, 1997;Kahveci & Xu, 2011;Rossi, Grosso, Pramparo, & Nepote, 2012;Zhang, Liu, & Liu, 2013). Other studies have used SPD to remove ethyl esters subsequently to ethanolysis in order to obtain an acylglycerol product (mainly DAG) rich in DHA and EPA (Lyberg & Adlercreutz, 2008;Martín Valverde, González Moreno, Rodríguez Quevedo, Hita Peña, Jiménez Callejón, Esteban Cerdán, et al, 2012;Valverde, Moreno, Callejón, Cerdán, & Medina, 2013).…”

The effect of industrial processing of salmon oil on its ability to reduce serum concentrations of oxidized low-density lipoprotein- β2-glycoprotein-I complex in a mouse model

“…Mice in Group G6 were given the same EVSO as in G4 containing 120mg/g EPA+DHA but treated with heat at 190C for 5 minutes to simulate vacuum molecular distillation. [ 28 ] Mice in Group G7 were given EVSO as in G4 but the EVSO was hydrolyzed with base and re-esterified with glycerol/acid as done in the standard fractional distillation step [ 29 ] often carried out for producing EPA/DHA concentrated fish oils. Finally, the mice in Group G8 were given EVSO as in G4 but the EVSO had been oxidized (by air bubbling) to reach a totox of 24 which is at the upper limit of the GOED standard.…”