Effect of Season on Salt-Extractable Protein in Muscle from Trawler-Caught Cod and on its Stability During Frozen Storage

1973 ◽  
Vol 30 (2) ◽  
pp. 157-160 ◽  
Author(s):  
C. H. Castell ◽  
Doris M. Bishop
Keyword(s):  
Lipid Content ◽  
Frozen Storage ◽  
Storage Quality ◽  
Seasonal Differences ◽  
Spawning Period ◽  
Extractable Protein

Periodical tests made on 272 fillets from fresh, postrigor, trawler-caught cod have shown that there is a slight decrease in salt-extractable proteins during the spring spawning period (March, April, and May). This was accompanied by a similar slight decrease in the lipid content of the muscle.When other fillets from these same lots of cod were frozen and stored at − 3.3 C and − 12 C, those from the fish caught during the spring spawning period tended to deteriorate faster, as indicated by the rate at which the EPN values decreased during storage. When the fish were stored at − 26 C for up to 2 years, the EPN changes during storage were so retarded that seasonal differences in storage quality could not be observed.

scholarly journals Effects of frozen storage on the proximate composition and formaldehyde content in some selected fish from three different sources of southern Bangladesh

2021 ◽  
Vol 32 (2) ◽  
pp. 303-312
Author(s):  
MD. BOKTHIER RAHMAN ◽  
MD. SAZEDUL HOQUE ◽  
SUPRAKASH CHAKMA ◽  
SHAIDA AKTER ◽  
S.M. OASIQUL AZAD ◽  
...  
Keyword(s):  
Marine Fish ◽  
Lipid Content ◽  
Proximate Composition ◽  
Frozen Storage ◽  
Ash Content ◽  
Health Concern ◽  
Formaldehyde Content ◽  
Fish Samples ◽  
Fresh Frozen ◽  
Different Sources

The study was conducted in aims to investigate the effects of frozen storage and cooking conditionson proximate compositions and formaldehyde content (FA) in some selected fish from three different sourcesin Bangladesh. Proximate composition in fresh and final frozen samples was determined by standard AOACmethod and FA content in fresh, frozen stored, and cooked samples was determined by spectrophotometricmethod. Among the studied fishes, marine fish contained higher protein (except Rita), lipid, and ash followedby estuarine and culture fish samples. Protein, moisture and ash content decreased and lipid content increasedsignificantly (p<0.05) during frozen storage for all samples and sources. The FA was lower in cultured fishsamples compared to that of the river and marine fish samples, both at fresh and end of frozen storage. Atfresh condition, FA content in all samples ranged from 0.41 to 0.71µg/g, 0.51 to 0.89µg/g, and 0.73 to1.69µg/g which increased to 0.95 to 2.11µg/g, 1.74 to 1.95µg/g, and 3.22 to 5.20µg/g at end of the storageperiod, respectively (p<0.05). Further, FA content significantly decreased after cooking in all the fishsamples (p<0.05). However, irrespective of fish species and sources, the FA content was higher than WHOrecommended value (0.2 µg/g). The study findings revealed that longer frozen storage of fish could be apublic health concern to the consumers.

Seasonal Changes in the Lipid Composition of Herring (Clupea Harengus) in Relation to Gonad Maturation

1989 ◽  
Vol 69 (2) ◽  
pp. 323-334 ◽  
Author(s):  
R.J. Henderson ◽  
S.M. Almatar
Keyword(s):  
Lipid Content ◽  
Lipid Composition ◽  
Seasonal Changes ◽  
Seasonal Cycle ◽  
Clupea Harengus ◽  
Gonad Maturation ◽  
British Isles ◽  
Spawning Period ◽  
Active Feeding

It is well established that the lipid content of the herring Clupea harengus from the waters around the British Isles and Ireland undergoes a marked seasonal cycle, being highest during the summer months of active feeding and lowest after a winter fast (Wood, 1958; lies & Wood, 1965; Lovern & Wood, 1937; Molloy & Cullen, 1981; Wallace, 1986). In the case of spring-spawning herring, the minimum lipid content coincides with the spawning period and the depletion of lipid over winter corresponds with the development of gonads (Lovern & Wood, 1937).

Effect of Stage of Rigor and of Freezing–Thawing Processes On Storage Quality of Refrozen Cod

1968 ◽  
Vol 25 (2) ◽  
pp. 299-320 ◽  
Author(s):  
J. A. Peters ◽  
J. W. Slavin ◽  
J. P. Lane ◽  
W. A. MacCallum ◽  
E. J. Laishley ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Frozen Storage ◽  
Taste Panel ◽  
Rigor Mortis ◽  
Protein Nitrogen ◽  
Circulating Water ◽  
Before And After ◽  
Extractable Protein

Trawler-caught cod were frozen before and after rigor mortis in brine (23% NaCI) and between refrigerated plates, thawed in circulating water at 7 C or in a conveyorized microwave oven, then processed into fillets which were packaged, plate-frozen, and stored at −18 C.All samples thawed satisfactorily in circulating water. Some overheating was encountered during thawing in microwaves. But the equipment was not developed sufficiently to permit assessment of the commercial potential of microwave thawing.Examinations of the fillets from the thawed fish for appearance, odor, and texture showed that freezing pre-rigor is preferable to freezing post-rigor and that thawing by means of microwaves is preferable to thawing by means of water. Freezing or thawing methods did not affect the pH of the thawed fillets.Results of organoleptic and chemical tests to determine the changes in quality of the refrozen fillets packaged and stored at −18 C for 12 months indicated that neither the average taste panel scores nor the chemical tests for moisture, total lipid, free fatty acids, and extractable protein nitrogen showed any difference attributable to state of rigor, freezing method, or thawing method. The taste panel slightly preferred the texture of fillets from fish frozen pre-rigor and from fish frozen in brine. Free fatty acids increased sharply as a result of thawing and refreezing, and the rapid increase continued during the first 2 months of frozen storage. Taste panel scores correlated significantly with free fatty acids (1% level) and with extractable protein (5% level).

Nucleotide Degradation in Frozen Swordfish Muscle

1969 ◽  
Vol 26 (6) ◽  
pp. 1597-1603 ◽  
Author(s):  
W. J. Dyer ◽  
Doris I. Hiltz
Keyword(s):  
Fish Species ◽  
Arrhenius Plot ◽  
Frozen Storage ◽  
Storage Period ◽  
Taste Panel ◽  
Storage Quality ◽  
Inosine Monophosphate ◽  
Red Muscle ◽  
Nucleotide Degradation ◽  
Storage Temperatures

In frozen swordfish steaks, inosine monophosphate (IMP) dephosphorylation was active at − 8 C and less so at − 18 C. A loss of IMP at − 26 C became apparent during a 2-year storage period. Rates of loss were about 0.24 and 0.029 μmoles per g per week at − 8 and − 18 C, the Arrhenius plot being linear over the temperature range 0 to − 26 C. Inosine ribohydrolase was less active; nevertheless, about 2.5 μmoles per g of hypoxanthine accumulated in 2 years at − 8 C. Taste panel tests indicated a storage life of 3 months at − 8 C, 9 months at − 18 C, and several years at − 26 C. The loss of IMP was slightly slower than the associated taste panel score decrease and thus may have potential as an indicator of frozen storage quality in some fish species, though it did not prove useful for swordfish. Hypoxanthine formation at low storage temperatures is sufficiently slow to allow use of hypoxanthine as an index of prefreezing quality; however, red muscle must not be included in the sample because of its high initial hypoxanthine content, about 1.9 μmoles per g.

Deteriorative Changes During Frozen Storage in Fillets and Minced Flesh of Silver Hake (Merluccius bilinearis) Processed from Round Fish Held in Ice and Refrigerated Sea Water

1976 ◽  
Vol 33 (11) ◽  
pp. 2560-2567 ◽  
Author(s):  
Doris Fraser Hiltz ◽  
Barbara Smith Lall ◽  
D. W. Lemon ◽  
W. J. Dyer
Keyword(s):  
Lipid Oxidation ◽  
Sea Water ◽  
Frozen Storage ◽  
Fat Content ◽  
Storage Life ◽  
High Fat ◽  
Lipid Hydrolysis ◽  
Extractable Protein ◽  
Silver Hake ◽  
Merluccius Bilinearis

During frozen storage at −10 C, deterioration in muscle of silver hake (Merluccius bilinearis) was marked by rapid and extensive production of dimethylamine, concomitant decrease in extractable protein, and by lipid hydrolysis. Evidence of lipid oxidation in this gadoid species of relatively high fat content (2–4%) was also obtained. In minced flesh the rates of deterioration were about twice as fast as in fillets. Holding round fish for up to 6 days in refrigerated sea water (RSW) at 0–1 C before processing extended the frozen storage life of fillets at −10 C by 2–3 wk and of minced flesh by 1 wk over that for comparable materials prepared from round fish held in ice. Materials prepared from winter (March) and summer (August) fish showed little or no difference in rates of deterioration. The susceptibility of silver hake to deterioration at −10 C is similar to cusk; deterioration is faster than in cod or haddock, but not as fast as in red hake (Urophycis chuss). In all silver hake materials negligible deterioration occurred during frozen storage at −26 C for up to 6 mo.During preprocessing storage of round silver hake in RSW, a firm texture and acceptable appearance were retained for several days longer than in round fish held in ice, where objectionable softening of the flesh occurred, particularly in summer-caught fish. Saturation of the sea water with CO2 retarded the onset of bacterial spoilage in RSW-held fish, which otherwise developed more rapidly than in iced fish.

Effects of Formaldehyde on Salt Extractable Proteins of Gadoid Muscle

1973 ◽  
Vol 30 (8) ◽  
pp. 1205-1213 ◽  
Author(s):  
C. H. Castell ◽  
B. Smith ◽  
W. J. Dyer
Keyword(s):  
Gadus Morhua ◽  
Atlantic Cod ◽  
Frozen Storage ◽  
Active Protein ◽  
Muscle Enzyme ◽  
Trimethylamine Oxide ◽  
Extractable Protein ◽  
Silver Hake ◽  
Merluccius Bilinearis ◽  
Fish Proteins

Addition of formaldehyde to fresh cod muscle, to give concentrations of 10 to 200 ppm, brought about marked decreases in the extractable protein content during holding periods of 24 hr or less at 0 C. Similar levels of formaldehyde, produced during frozen storage of gadoid (Atlantic cod, Gadus morhua, pollock, Pollachius virens, cusk, Brosme brosme, and silver hake, Merluccius bilinearis), fillets at −5 C, brought about similar reductions in the extractable proteins. Comparative tests showed that, in the concentrations normally encountered in deteriorating frozen gadoid fillets, formaldehyde was a much more active protein-insolubilizing agent than free fatty acid. It is evident that in these protein changes more than one mechanism is involved. Observed species-differences in the extent to which fish proteins became insolubilized during storage appeared to be related to presence or absence of these different mechanisms. The more rapid and more extensive denaturation of most gadoid fillets in frozen storage than of fillets of nongadoid species appears to be directly related to the presence of muscle enzyme of the former group that is capable of producing formaldehyde from trimethylamine oxide, which is absent in the muscle of the nongadoid species so far tested.

Seasonal variations in diet of arrow squid (Nototodarus gouldi): stomach content and signature fatty acid analysis

2011 ◽  
Vol 92 (1) ◽  
pp. 187-196 ◽  
Author(s):  
H. Pethybridge ◽  
P. Virtue ◽  
R. Casper ◽  
T. Yoshida ◽  
C.P. Green ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Stomach Content ◽  
Lipid Content ◽  
Total Lipid Content ◽  
Monounsaturated Fatty Acids ◽  
Stomach Content Analysis ◽  
Fatty Acid Analysis ◽  
Mesopelagic Fish ◽  
Seasonal Differences ◽  
Life History Stages

This study details the feeding ecology of arrow squid,Nototodarus gouldi, collected opportunistically from trawlers in waters south-east off Australia in 2007 and 2008. Combined stomach content and fatty acid (FA) signature analyses provided clear evidence of seasonal dietary shifts in prey composition. Teleost fish remains (mainly otoliths) were found in 67% of stomachs with the two mesopelagic planktivorous fish,Lampanyctodes hectorisandMaurolicus muelleridominating. Cephalopods and crustaceans were supplementary dietary components, with an increased representation in the diet over winter. Digestive gland lipid content was moderate (16.4 ± 8.4% wet weight) and was rich in triacylglycerol and monounsaturated fatty acids. Multivariate analysis of FA profiles grouped arrow squid with profiles of mesopelagic fish and cephalopods, thus supporting the findings of stomach content analysis. Seasonal differences in total lipid content were likely related to summer upwelling events and local changes in productivity, while intraspecific differences in lipid class and FA composition were related to seasonal differences of prey consumption. FA analyses also demonstrated dietary differences associated with gender, size and female maturation. Such relationships demonstrate that the diet ofN. gouldiis closely linked to prey size, abundance and availability and possibly also, to key life-history stages.

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