Stability of Golden redfish (Sebastes marinus) during frozen storage as affected by raw material freshness and season of capture

SNPS within the SLC27A6 gene are highly associated with Hu sheep fatty acid content

Fatty acids (FA) are an important factor affecting meat quality and human health, and the important role of the solute carrier family 27 member 6 (SLC27A6) in FA metabolism has been demonstrated in several species. However, the expression profile of the SLC27A6 in different tissues and the effect of its polymorphism on FA in sheep are currently unknown. This study aimed to explore the differences in FAs in the longissimus dorsi (LD) of 1,085 Hu sheep, the expression profile of SLC27A6, and confirm the effect of single nucleotide polymorphisms (SNPs) on FA phenotypes. We found that many FA phenotypes differ significantly across different seasons, and winter promoted the deposition of polyunsaturated fatty acids (PUFA). The mRNA expression level of SLC27A6 in the lung was significantly higher than that in the heart, testis, and LD. A total of 16 SNPs were detected in the SLC27A6, and 14 SNPs were successfully genotyped by improved multiplex ligase detection reaction (iMLDR) technology. Correlation analysis showed that 7 SNPs significantly affected at least one FA phenotype. Among them, SNP14 contributes to the selection of lamb with low saturated fatty acid content and high PUFA content. Combined genotypes also significantly affected a variety of beneficial FAs such as C18:3n3, C20:4n6, C22:6n3, and monounsaturated fatty acids. This study suggests that SLC27A6 plays an important role in FA metabolism and SNPs that are significantly associated with FA phenotype could be used as potential molecular markers for later targeted regulation of FA profiles in sheep.

Comparative Analysis of Lipids and Fatty Acids in Beaked Redfish Sebastes mentella Travin, 1951 Collected in Wild and in Commercial Products

The lipid and fatty acid profile of muscles in beaked redfish, caught and fixed in the wild versus specimens from food supermarkets (“commercial”), were evaluated, as well as the health implications of this popular food for its consumers based on the calculation of nutritional quality indexes. The contents of the total lipids (TLs), total phospholipids (PLs), monoacylglycerols (MAGs), diacylglycerols (DAGs), triacylglycerols (TAGs), cholesterol (Chol), Chol esters, non-esterified fatty acids (NEFAs), and wax esters were determined by HPTLC; the phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC), and lysophosphatidylcholine (LysoPC) were determined by HPLC; and fatty acids of total lipids were determined using GC. The TL content was higher in commercial products due to DA and NEFAs, among PL fractions the content of LysoPC was also higher. The results indicated multidirectional processes of slight degradation of lipids in commercial products in comparison to wild. The flesh lipid quality index was lower due to EPA and DHA in commercial specimens while the index of thrombogenicity was significantly higher. The differences in the quantities of lipid classes between muscle biopsy regions in fish apparently corroborate the morphology and physiology of deep-water fish.

Current freezing and thawing scenarios employed by North Atlantic fisheries: their potential role in Newfoundland and Labrador's northern cod (Gadus morhua) fishery

Seafood is very perishable and can quickly spoil due to three mechanisms: autolysis, microbial degradation, and oxidation. Primary commercial sectors within the North Atlantic fisheries include demersal, pelagic, and shellfish fisheries. The preservation techniques employed across each sector can be relatively consistent; however, some key differences exist across species and regions to maintain product freshness. Freezing has long been employed as a preservation technique to maintain product quality for extended periods. Freezing allows seafood to be held until demand improves and shipped long distances using lower-cost ground transportation while maintaining organoleptic properties and product quality. Thawing is the opposite of freezing and can be applied before additional processing or the final sale point. However, all preservation techniques have limitations, and a properly frozen and thawed fish will still suffer from drip loss. This review summarizes the general introduction of spoilage and seafood spoilage mechanisms and the latest preservation techniques in the seafood industry, focusing on freezing and thawing processes and technologies. This review also considers the concept of global value chains (GVC) and the points to freeze and thaw seafood along the GVC to improve its quality with the intention of helping Newfoundland and Labrador’s emerging Northern cod (Gadus morhua) fisheries enhance product quality, meet market demands and increase stakeholder value.

Determination and Comparison of Physical Meat Quality Parameters of PERCIDAE and Salmonidae in Aquaculture

Although aquaculture has been the fastest growing food sector for decades, there are no standardized parameters for most of the fish species regarding physical meat quality. Therefore, this study provides for the first time an overview of the physical meat characteristics of the most important fish species of the German Baltic Sea coast. Traditional farmed salmonids (rainbow trout (Oncorhynchus mykiss) and maraena whitefish (Coregonus maraena) as well as two percids (European perch, Perca fluviatilis and pikeperch, Sander lucioperca) were utilized for this comparison. The results demonstrate that the meat of the salmonids is very analogous. However, the post mortem degradation process starts faster in trout meat. In contrast, the meat quality characteristics of the percids are relatively different. The meat of pikeperch has comparatively low shear strength with a high water-holding capacity resulting in high meat tenderness. The opposite situation is present in European perch. The results indicate that it is not possible to establish the overall quality characteristics for fish or production form, as there is a high range of variability. Consequently, it is particularly important that meat quality characteristics are developed for important aquaculture species for further improvement through changes in husbandry conditions when necessary.