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.

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Influence of climatic changes on the parasites of Atlantic cod Gadus morhua off coastal Labrador, Canada

Journal of Helminthology ◽

10.1079/joh2006352 ◽

2006 ◽

Vol 80 (2) ◽

pp. 193-197 ◽

Cited By ~ 8

Author(s):

R.A. Khan ◽

C.V. Chandra

Keyword(s):

North Atlantic ◽

Gadus Morhua ◽

Atlantic Cod ◽

Age Groups ◽

Climatic Conditions ◽

Otter Trawl ◽

Commercial Fishery ◽

Metazoan Parasites ◽

Mean Values ◽

The North

AbstractA study was conducted in 2000 and 2003, following the collapse of the commercial fishery in 1990, to compare metazoan parasites of Atlantic cod Gadus morhua, captured off coastal Labrador, with samples taken in 1980 and 1986. Fish were captured by otter trawl offshore in the North Atlantic Fish Organisation subarea 2J. Parasites were removed from the digestive tract, stained, identified and compared between the different groups. Both the prevalence and mean abundance of trematodes, larval nematodes and E. gadi were significantly lower in fish taken in 2000 and 2003 than in 1980. While mean values of trematodes and nematodes declined in 1986, those of Echinorhynchus gadi remained unchanged in 1986 and 1990. Four-year-old cod sampled in 1990 harboured significantly fewer E. gadi than older age groups. The most commonly occurring trematodes included Podocotylereflexa, Lepidapedon elongatum, Derogenes varicus and Hemiurus levinseni while the larval nematode, Anisakis sp. was predominant. Comparison of offshore samples taken in 2000 and 2003 with others taken in previous years suggests an overall decline of parasites coincident with a change in climatic conditions, the absence of a major food source, namely capelin Mallotus villosus, of cod and ultimately the decline of the Labrador population.

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Comparison of the response of Atlantic cod (Gadus morhua) in the high-latitude regions of the North Atlantic during the warm periods of the 1920s–1960s and the 1990s–2000s

Deep Sea Research Part II Topical Studies in Oceanography ◽

10.1016/j.dsr2.2008.12.001 ◽

2009 ◽

Vol 56 (21-22) ◽

pp. 2087-2096 ◽

Cited By ~ 37

Author(s):

Ken Drinkwater

Keyword(s):

North Atlantic ◽

High Latitude ◽

Gadus Morhua ◽

Atlantic Cod ◽

The North ◽

The North Atlantic

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Artificial light in baited pots substantially increases the catch of cod (Gadus morhua) by attracting active bait, krill (Thysanoessa inermis)

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy099 ◽

2018 ◽

Vol 75 (6) ◽

pp. 2257-2264 ◽

Cited By ~ 8

Author(s):

Odd-Børre Humborstad ◽

Anne Christine Utne-Palm ◽

Michael Breen ◽

Svein Løkkeborg

Keyword(s):

Light Source ◽

North Atlantic ◽

Coastal Waters ◽

Gadus Morhua ◽

Catch Rate ◽

Light Sources ◽

The North ◽

Important Prey ◽

Large Numbers ◽

Per Se

Abstract The use of pots in the north Atlantic finfish fisheries is negligible because this fishing method typically has a low capture efficiency. Large numbers of individuals encounter baited pots, but the proportions of fish that enter the pot and become caught are low. Krill, which constitutes an important prey for cod (Gadus morhua), is attracted by light. The catching efficiency of baited cod pots with three light sources with different colours and intensities (white: 9744 mW m−2, white: 23 mW m−2, green: 8 mW m−2) were tested in coastal waters in northern Norway. Pots with the light source of highest intensity gave a 17 times higher catch rate of cod than that of control pots (with bait only). The light source of medium intensity gave about a five times higher catch rate, whereas the weakest light did not influence the catch. Cod caught in pots with light had more krill and arrowworms in their stomach and were observed feeding on these preys inside the pot. We concluded that light sources of increasing intensity attract more krill, and that cod were attracted into the pot by the dense swarms of prey and not the light per se.

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Greenland halibut (Reinhardtius hippoglossoides) in the North Atlantic are genetically homogeneous

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-088 ◽

1997 ◽

Vol 54 (8) ◽

pp. 1813-1821 ◽

Cited By ~ 28

Author(s):

M L Vis ◽

S M Carr ◽

W R Bowering ◽

W S Davidson

Keyword(s):

North Atlantic ◽

Gadus Morhua ◽

Genetic Distances ◽

Greenland Halibut ◽

Western Atlantic ◽

Grand Banks ◽

The North ◽

Greenland Halibut Reinhardtius Hippoglossoides ◽

The North Atlantic ◽

Reinhardtius Hippoglossoides

Greenland halibut (Reinhardtius hippoglossoides) have become of great importance to the Canadian fishery since the moratorium on northern cod (Gadus morhua), and an understanding of stock relationships among populations at the northern and southern extremes of their commercial range is crucial for proper management. We compared mitochondrial DNA sequence variation among fish taken from thoughout the Northwest Atlantic (Flemish Pass, the Grand Banks, Davis Strait, and Northwest Greenland) with samples from the Gulf of St. Lawrence, Iceland, and Norway. Within a 401 base pair portion of the cytochrome b gene, 22 genotypes were identified. Three of these occur at frequencies >10% and in the same relative abundances in all samples (except the Gulf of St.Lawrence). Genotype proportions do not differ significantly among samples, and genetic subdivision among samples (measured by the coancestry coefficient theta ) is nil. Genetic distances among samples are not related to geographic distribution: pairwise differences between the Gulf sample and other western Atlantic samples exceed those for trans-Atlantic comparisons. These data suggest that there is sufficient mixing of Greenland halibut, not only within the NAFO regulatory area, but among sites in the North Atlantic generally, to prevent the development or maintenance of genetically independent stocks.

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Temperature and the recruitment of Atlantic cod (Gadus morhua)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-114 ◽

1999 ◽

Vol 56 (11) ◽

pp. 2069-2077 ◽

Cited By ~ 177

Author(s):

B Planque ◽

T Frédou

Keyword(s):

North Atlantic ◽

Gadus Morhua ◽

Cold Water ◽

Atlantic Cod ◽

The Other ◽

Warm Water ◽

The North ◽

The North Atlantic ◽

Interannual Fluctuations ◽

The Relationship

Variability in the recruitment of fish has been attributed to either changes in the environment or variations in the size of reproductive stocks. Disentangling the effects of environment and stock has proven to be problematic and has resulted in recurrent controversy between studies supporting either hypothesis. In the present study, we examine the relationship between interannual changes in temperature and variation in recruitment for nine Atlantic cod (Gadus morhua) stocks in the North Atlantic. We show that for individual stocks, the relationship often appears weak and statistically not significant. On the other hand, by combining in a single metaanalysis the results from individual stocks, we demonstrate that recruitment of Atlantic cod is linked to interannual fluctuations in temperature in such a way that for stocks located in warm water the relationship is negative, for stocks located in cold water the relationship is positive, and there is no relationship for stocks located in the middle of the temperature range.

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