Differential lipid damage in various muscle zones of frozen hake ( Merluccius merluccius )

Abstract

SUMMARYA comparison of the lipid damage produced in different hake zones was carried out during the frozen storage at -11°C and -18°C. Three light muscle zones and the dark muscle were considered. Lipid oxidation (conjugated dienes; thiobarbituric acid index, TBA-i; fluorescence formation) and hydrolysis (free fatty acids, FFA) were determined.The most predominant lipid damage in all zones was hydrolysis, reaching at the end of the storage values round 40% (for the light muscle zones) and 12% (for the dark muscle) of total lipids at -11°C. Significant (p<0.05) correlation values (r = 0.67-0.85) relationships between the frozen storage time and the FFA content were obtained for the four muscle zones at both temperatures. A comparison of regression lines slopes in the different zones showed that a lower (p<0.05) lipolitic activity was produced in the dark muscle compared to the three light zones at both temperatures. A low lipid oxidation development was produced in the three light muscle parts so that no significant differences between themselves could be assessed. However, the dark muscle showed a higher oxidation development (TBA-i and fluorescence formation) as a result of a higher lipid content and the presence of prooxidant constituents.

Effect of slurry ice on chemical changes related to quality loss during European Hake ( Merluccius merluccius ) chilled storage

“…Both results agreed to previous hake studies [20,29]. Differences in both constituents may be explained as a result of fish-tofish variations and not derived from chilling conditions and storage time.…”

“…Formation of fluorescent compounds were determined with a Perkin Elmer LS 3B fluorimeter by measurements at 393/463 nm and 327/415 nm, as previously described [19,20]. The relative fluorescence (RF) was calculated as follows: RF = F/F st , where F is the fluorescence measured at each excitation/emission maximum, and F st is the fluorescence intensity of a quinine sulphate solution (1 µg/mL in 0.05 M H 2 SO 4 ) at the corresponding wavelength.…”

Lipid damage during frozen storage of Gadiform species captured in different seasons

“…In the case of frozen gadiform species, quality loss has been mainly associated with formaldehyde formation and its implications in quality loss [6,7]. However, lipid hydrolysis and oxidation have been shown to occur and have become important factors of gadiform fish acceptance during the frozen storage as they influence the sensory quality [8], protein denaturation, texture changes, functionality loss [9][10][11] and formation of complexes with proteins [12,13].…”

Active Packaging Film Based in Natural Antioxidant from Barley Husks and Effect over Lipid Damage of Frozen Swordfish (Xiphias gladius)

“…Enzymatic hydrolysis of lipids occurs even during storage of frozen fish. Formation of FFA does not entail loss of nutritional value but its accumulation has been associated with a decrease in acceptability of food by the consumer (Aubourg et al, 1999). The decrease in consumer acceptance of frozen fish has been related to accumulation of FFA, because these compounds have deleterious effects on ATPase activity, protein solubility, and cause disagreeable flavors, discoloration, viscosityrelated deterioration of the texture (due to interactions between proteins), and oxidize more rapidly to form higher molecular weight lipids (triglycerides and phospholipids), thus providing greater accessibility (lower steric effect) to d.a.…”