Effect of Bleeding/Gutting Procedures on the Sensory Quality of Fresh Raw Atlantic Cod (Gadus morhua)

AbstractTrawl-caught Atlantic cod (Gadus morhua) often yield highly variable fillet quality that may be related to capture stress. To investigate mechanisms involved in causing variable quality, commercial-sized (3.5±0.9 kg) Atlantic cod were swum to exhaustion in a large swim tunnel and subsequently exposed to extreme crowding (736±50 kg m-3) for 0, 1 or 3 hours in an experimental cod-end. The fish were then recuperated for 0, 3 or 6 hours in a net pen prior to slaughter to assess the possibility to reverse the reduced fillet quality. We found that exhaustive swimming and crowding were associated with increased metabolic stress, as indicated by increased plasma cortisol, blood lactate and blood haematocrit levels, accompanied by reduced quality of the fillets due to increased visual redness and lower initial muscle pH. The observed negative effects of exhaustive swimming and crowding were only to a small degree reversed within 6 hours of recuperation. The results from this study suggest that exhaustive swimming followed by extreme crowding can reduce fillet quality and contribute to the variable fillet quality seen in trawl-caught Atlantic cod. Recuperation for more than six hours may be required to reverse these effects.

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Effect of Antarctic krillmeal on quality of farmed Atlantic cod (Gadus morhua L.)

Aquaculture Research ◽

10.1111/j.1365-2109.2006.01615.x ◽

2006 ◽

Vol 37 (16) ◽

pp. 1676-1684 ◽

Cited By ~ 13

Author(s):

Ørjan Karlsen ◽

Jorma Suontama ◽

Rolf Erik Olsen

Keyword(s):

Gadus Morhua ◽

Atlantic Cod

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Quality of Nephrops as food for Atlantic cod (Gadus morhua L.) with possible implications for fisheries management

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2004.06.017 ◽

2004 ◽

Vol 61 (6) ◽

pp. 983-991 ◽

Cited By ~ 5

Author(s):

Björn Björnsson ◽

Maria Álvaro Dongala Dombaxe

Keyword(s):

Growth Rate ◽

Gadus Morhua ◽

Specific Growth ◽

Condition Factor ◽

Atlantic Cod ◽

Gonadosomatic Index ◽

Conversion Ratio ◽

Food Conversion ◽

The Mean

Abstract Nephrops was found to be of low quality as food for cod. In a laboratory experiment the mean specific growth rate of 1 kg cod was 0.184 and 0.415% d−1 when fed to satiation on Nephrops and capelin, respectively. This large difference in growth rate resulted not only from less intake of Nephrops (1.19 kg cod−1) than capelin (1.55 kg cod−1) but also because more Nephrops (4.6 kg) than capelin (2.2 kg) were required to produce each kilogramme of cod. Higher food conversion ratio was consistent with lower fat content of Nephrops (1.3%) than capelin (9.2%) but the exoskeleton also reduced the digestion rate of Nephrops. In the groups where Nephrops and capelin of equal mean weight were offered simultaneously, 40% of the diet consisted of Nephrops during the first week and 10% during the final seven weeks of the experiment. At the end of the experiment, condition factor, liver index, and gonadosomatic index were significantly lower for cod fed on Nephrops (0.967, 5.7, 7.1, respectively) than for those fed on capelin (1.086, 15.8, 11.2, respectively). These results suggests that predation by cod on Nephrops might be reduced by regular release of capelin or other similar food in the distributional areas of Nephrops.

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Impact of dietary oil source on product quality of farmed Atlantic cod, Gadus morhua

Aquaculture ◽

10.1016/j.aquaculture.2007.01.033 ◽

2007 ◽

Vol 267 (1-4) ◽

pp. 236-247 ◽

Cited By ~ 39

Author(s):

Turid Mørkøre ◽

Charlotte Netteberg ◽

Lars Johnsson ◽

Jana Pickova

Keyword(s):

Product Quality ◽

Gadus Morhua ◽

Atlantic Cod ◽

Oil Source ◽

Dietary Oil

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Taste Panel Assessment of Cod Fillets After Single and Double Freezing

Journal of the Fisheries Research Board of Canada ◽

10.1139/f66-097 ◽

1966 ◽

Vol 23 (7) ◽

pp. 1063-1081 ◽

Cited By ~ 6

Author(s):

W. A. MacCallum ◽

E. J. Laishley ◽

W. J. Dyer ◽

D. R. Idler

Keyword(s):

Gadus Morhua ◽

Cold Water ◽

Atlantic Cod ◽

Tap Water ◽

Poor Quality ◽

Taste Panel ◽

Rigor Mortis ◽

Trap Fishery ◽

And Storage

Taste panel assessment is reported for Atlantic cod (Gadus morhua) frozen once and twice, and stored at −23 C. The fish were bled, gutted, and iced immediately after capture, and frozen as fillets or dressed fish before, during, and after rigor mortis. Dressed fish were thawed later in recirculated tap water, then processed, refrozen, and stored as fillets. The procedure was conducted three times (June 27, July 19, July 30) during the inshore trap fishery and twice (March and October) during the offshore Grand Bank fishery.For trap-caught landings, the quality of the stored fillets frozen once depended upon the season of catch; for Grand Bank cod, upon the time and place of catching. Trap fish, feeding lightly, caught in cold water in June, were of best quality, grades equalling 70 and over after 20 weeks storage. Those caught on July 30 while feeding heavily in warm water were second; the July 19 fish, obtained under nearly similar conditions, were not significantly poorer than those taken on July 30 and were still acceptable. March landings of Grand Bank fish, once frozen, scored over 70 after 20 weeks storage; October landings only 40 (borderline quality) after 30 weeks. Physiochemical and chemical assessment confirmed the poor quality of the latter.Thawing, refreezing, and storage of June trap fish longer than a few weeks resulted in poor but still acceptable samples. The stored product was soon similar in quality to samples prepared from July landings. In contrast, twice-frozen samples prepared from the March landings from the Grand Bank continued to score high, 70 after 28 weeks storage. Refrozen October samples from the Grand Bank yielded much lower scores, similar to those given the once-frozen samples of the same catch. Thus, in general, an acceptable or better twice-frozen product was obtained by starting with material well handled and quickly chilled, from either the inshore or offshore fishery.

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