Lipid Extraction with Electrolyzed Cathode Water from Marine Products

Abstract

Edible (muscle with skin) and non-edible (viscera, head and bone) parts of fish were homogenized with chloroform/methanol (2:1, v/v) according to the method of Bligh & Dyer to extract lipids. These fish products were also homogenized with distilled water (DW), NaCl solution and electrolyzed cathode water (EW(-)). The aqueous homogenate was centrifuged and filtered, and then the lipids in the aqueous filtrate were recovered by hexane extraction. The content of lipid obtained by the Bligh & Dyer method from edible and non-edible parts of saury was higher than those by extractions with DW and NaCl solution. On the other hand, EW(-) extraction showed higher lipid content than the Bligh & Dyer method in this case. Nevertheless, the lipid extraction ability of EW(-) was decreased when exposed to air for 7 days, showing that high pH and/or high dissolved hydrogen may be responsible for the effect of EW(-). The present study also showed the ability of EW(-) in effective lipid extraction from other kinds of fish products such as edible and non-edible parts of mackerel, sardines, tuna orbital and trout eggs.