Canned cod liver as a source of n-3 polyunsaturated fatty acids, with a reference to contamination.
Lipid composition (HPLC), fatty acid composition (GC/MS), lipid oxidation (peroxide value, anisidine value), UV-VIS and fluorescence spectra (Ex 365 nm), and susceptibility of lipids to oxidation (photooxidation test) as well as heavy metal, PCB, and DDT contents were determined in canned, raw, and thermally treated cod liver (separately in the released oil and in the solids). Canned products of three manufacturers were examined. Mean contents of n-3 polyunsaturated fatty acids (n-3 PUFAs) in the oil and solids were 31.91 +/- 1.83 and 16.59 +/- 7.48 g/100 g, respectively, the respective contents of docosahexaenoic acid (DHA) being 17.88 +/- 1.69 and 8.79 +/- 3.67 g/100 g. Lipid resistance to oxidation was found to decrease after thermal treatment of livers. However, the lipid oxidation level in canned liver stored for 3-8 months was not high and averaged, for the entire can content, 0.47 +/- 0.4 Meq O, the oil being more susceptible to oxidation that the solids. It is concluded that canned cod liver is a very good source of n-3 PUFA, particularly with respect to DHA. Heavy metal, DDT, and PCB contamination and the presence of lipid oxidation products in the canned products tested remain at a level producing no perceivable health hazard and could in no way interfere with consumption of recommended amounts of n-3 PUFAs.
Kołakowska
A
A
University of Agriculture in Szczecin, Faculty of Food Sciences and Fisheries, Department of Food Quality, Papieza Pawla VI St. 3, PL-71-459 Szczecin, Poland. akolakowska@tz.ar.szczecin.pl
Stypko
K
K
Domiszewski
Z
Z
Bienkiewicz
G
G
Perkowska
A
A
Witczak
A
A
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003060:Cod Liver Oil / Q000032:analysis* / Q000528:radiation effects; D003116:Color; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005506:Food Contamination; D005511:Food Handling; D005519:Food Preservation; D005525:Food-Processing Industry; D008401:Gas Chromatography-Mass Spectrometry; D006358:Hot Temperature; D008099:Liver / Q000737:chemistry* / Q000378:metabolism; D019216:Metals, Heavy / Q000032:analysis*; D010084:Oxidation-Reduction; D017747:Seafood / Q000032:analysis; D013649:Taste
D015525:Fatty Acids, Omega-3; D019216:Metals, Heavy; D003060:Cod Liver Oil