title: The effect of natural antioxidants on haemoglobin-mediated lipid oxidation during enzymatic hydrolysis of cod protein.
abstract: Heating and changes in pH often practised during fish protein hydrolysis can cause lipid oxidation. The effect of natural antioxidants towards haemoglobin-mediated lipid oxidation during enzymatic hydrolysis of cod proteins was investigated. Different variants of a washed cod model system, containing different combinations of haemoglobin and natural antioxidants (l-ascorbic acid and Fuscus vesiculosus extract), were hydrolysed using Protease P "Amano" 6 at pH 8 and 36°C to achieve 20% degree of hydrolysis. Lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS) were analysed periodically during the hydrolysis process. The in vitro antioxidant activity of the final products was investigated. Results indicate that oxidation can develop rapidly during hydrolysis and antioxidant strategies are preferable to produce good quality products. Oxidation products did not have an impact on the in vitro antioxidant activity of the hydrolysates. The natural antioxidants inhibited oxidation during hydrolysis and contributed to the antioxidant activity of the final product.
authors.affiliation: Matis, Vinlandsleid 12, 113 Reykjavík, Iceland. sigrun.m.halldorsdottir@matis.is
authors.forename: Sigrun M
authors.initials: SM
authors.lastname: Halldorsdottir
authors.forename: Hordur G
authors.initials: HG
authors.lastname: Kristinsson
authors.forename: Holmfridur
authors.initials: H
authors.lastname: Sveinsdottir
authors.forename: Gudjon
authors.initials: G
authors.lastname: Thorkelsson
authors.forename: Patricia Y
authors.initials: PY
authors.lastname: Hamaguchi
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D005396:Fish Products / Q000032:analysis*; D029941:Fish Proteins / Q000737:chemistry*; D005511:Food Handling; D044645:Fucus / Q000737:chemistry*; D048389:Gadus morhua; D006454:Hemoglobins / Q000737:chemistry*; D006868:Hydrolysis / Q000187:drug effects; D008055:Lipids / Q000737:chemistry*; D008460:Meat / Q000032:analysis; D018482:Muscle, Skeletal / Q000737:chemistry; D010084:Oxidation-Reduction / Q000187:drug effects; D010447:Peptide Hydrolases / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D029941:Fish Proteins; D006454:Hemoglobins; D008055:Lipids; D010447:Peptide Hydrolases; D001205:Ascorbic Acid