Condition of Newfoundland Trap-Caught Cod and Its Influence on Quality After Single and Double Freezing

1968 ◽  
Vol 25 (4) ◽  
pp. 733-755 ◽  
Author(s):  
W. A. MacCallum ◽  
June I. Jaffray ◽  
D. N. Churchill ◽  
D. R. Idler
Keyword(s):  
Gadus Morhua ◽  
Ph Measurements ◽  
Protein Nitrogen ◽  
Overall Acceptability ◽  
Low Temperature Storage ◽  
Before And After ◽  
Extractable Protein ◽  
Frozen Fish ◽  
Quality Assessments ◽  
Better Than

Quality assessments, based on organoleptic evaluations and chemical tests, were conducted before and after cold storage, on trap-caught cod (Gadus morhua) which was unfrozen, once-frozen, or twice-frozen. The cod was processed both before and during rigor, after icing or after handling without ice, at various times during the catching season.Lactate determinations and pH measurements on whole fish at killing showed a seasonal variation. There was a correlation between lactate determinations and pH measurements in freshly killed and freshly frozen fillets that had been frozen both before and during rigor. Icing immediately after killing slowed the rate of lactate accumulation.Differences in the state of pre- and in-rigor chilled fish at freezing, as assessed by muscle glycogen, lactate, and reserves of ATP, resulted in differences in texture, thaw-drip, and pH. Patterns in texture may be predicted by the amounts of thaw-drip and the pH measured in the cold-stored pack.Intensity of mealiness and short-grained features in freshly frozen (once) fish was correlated with the level of ATP immediately before cooking. Fillets frozen before rigor toughened very slowly in storage at −23 C and the mealy condition eventually disappeared. Hence, fish downgraded for mealiness at freezing improved or maintained initial overall texture scores during 6 months in storage. Although the panel showed a clear preference for fish frozen pre-rigor, it would be impossible for industry to freeze more than a portion of the landings pre-rigor. To obtain the next best once-frozen product, chilled in-rigor fish should be processed.Double freezing gave the next best product from chilled, prerigor fish. Fish frozen pre-rigor in the "dressed" condition and stored at −23 C, then thawed, processed, and refrozen at 16 weeks, was equal in quality to once-frozen controls. The texture in the twice-frozen material prepared from iced, prerigor frozen fish dropped after a further 10 weeks storage, making it little better than the twice-frozen product of commercial-like handling. A very satisfactory twice-frozen product was obtained also by holding unfilleted blocks of non-iced, gutted fish at −46 C before thawing and refreezing, followed by remaining storage at −23 C. However, such low temperature storage is not within the scope of present commercial operations.With pre- and in-rigor frozen material a correlation was found between thaw-drip and pH, thaw-drip and overall texture (in-rigor freezing only), pH and overall texture values, and between pH and toughness. There was also a correlation between extractable protein nitrogen (EPN) values and overall texture scores of fish frozen in various stages of rigor (encountered during unfrozen storage of upwards of 24 hr before processing) but not between EPN and overall acceptability. With twice-frozen fillets prepared from material also handled unfrozen as above, there was significant correlation between EPN values at tasting and overall texture scores and between EPN and overall acceptability scores.Free fatty acid (FFA) values of the trap fish were high and showed no increase as the result of thawing and refreezing or further storage at −23 C or with pre- and in-rigor freezing. Storage at −46 C resulted in less FFA development. There was significant correlation between EPN and FFA values for June-caught once-frozen fish and between FFA values and strictly taste scores for June and July fish but no correlation between FFA and overall texture scores, or in the case of twice-frozen fish of any particular pre-freezing treatment, between FFA and taste, overall texture, or overall acceptability.

Comparison of Changes in Trimethylamine, Dimethylamine, and Extractable Protein in Iced and Frozen Gadoid Fillets

1973 ◽  
Vol 30 (8) ◽  
pp. 1246-1248 ◽  
Author(s):  
C. H. Castell ◽  
W. E. Neal ◽  
J. Dale
Keyword(s):  
Gadus Morhua ◽  
Atlantic Cod ◽  
The Other ◽  
Protein Nitrogen ◽  
Extractable Protein ◽  
Frozen Fish ◽  
Silver Hake ◽  
Merluccius Bilinearis

When fillets of Atlantic cod (Gadus morhua), pollock (Pollachius virens), cusk (Brosme brosme), and silver hake (Merluccius bilinearis) were iced and the opposite fillets frozen, large amounts of trimethylamine were rapidly produced in the iced fish but none was formed in the frozen fish within 60 days. Hake produced large, similar amounts of dimethylamine (DMA) in iced and frozen fillets. The other three species produced more DMA in the frozen than in the iced fillets, but always much less than in the hake. In both frozen and iced fish the production of DMA was accompanied by a corresponding decrease in extractable protein nitrogen.

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).

Polyphosphate Treatment of Frozen Cod. 2. Effect on Drip, Yield, Lipid Hydrolysis and Protein Extractability in Twice-Frozen Newfoundland Summer Trap and Fall Cod

1964 ◽  
Vol 21 (3) ◽  
pp. 539-548 ◽  
Author(s):  
W. A. MacCallum ◽  
H. S. Shieh ◽  
Dorothy A. Chalker ◽  
W. J. Dyer ◽  
D. R. Idler
Keyword(s):  
Gadus Morhua ◽  
Protein Denaturation ◽  
Sodium Tripolyphosphate ◽  
Fatty Acid Production ◽  
Lipid Hydrolysis ◽  
Fish Samples ◽  
Frozen Fish ◽  
Free Fatty Acid Production ◽  
Protein Extractability ◽  
Better Than

Thaw-drip from once-frozen fall-caught Newfoundland cod (Gadus morhua L.), thawed after storage at −23 °C for up to [Formula: see text] weeks, was equal to total drip from twice-frozen fish treated with sodium tripolyphosphate between freezings. Treatment of twice-frozen cod before the first freezing only had no effect on reducing total thaw-drip below that from twice-frozen untreated samples and the yield, although higher in the former than in the latter, was no better than that from once-frozen untreated fillets. Yields from twice-frozen fish were improved greatly by dipping prior to the second freezing and by dipping before each freezing. Treatment between freezings gave yields close to 100% of initial fillet weight whereas losses with the untreated once- and twice-frozen product appear close to 7 and 15%, respectively.With summer-caught trap fish, characterized by higher thaw-drip values which were not affected by treatment, yields of twice-frozen cod were improved; however, losses were still about 12% in fish treated between freezings.Treatment of twice-frozen cod from the two sources did not appreciably affect lipid hydrolysis or protein denaturation. However, lipid content and free fatty acid production were significantly higher in the trap fish samples as compared to the fall-caught cod.

Kepuasan Masyarakat Terhadap Pelayanan Kelurahan Setelah Pemekaran Di Tangerang Selatan

Liquidity ◽  
2018 ◽  
Vol 2 (2) ◽  
pp. 151-159
Author(s):  
Pitri Yandri
Keyword(s):  
Public Perception ◽  
Service Personnel ◽  
Urban Services ◽  
Hospitality Workers ◽  
Care Workers ◽  
Before And After ◽  
Cartesian Diagram ◽  
Better Than

The purpose of this study is (1) to analyze public perception on urban services before and after the expansion of the region, (2) analyze the level of people's satisfaction with urban services, and (3) analyze the determinants of the variables that determine what level of people's satisfaction urban services. This study concluded that first, after the expansion, the quality of urban services in South Tangerang City is better than before. Secondly, however, public satisfaction with the services only reached 48.53% (poor scale). Third, by using a Cartesian Diagram, the second priority that must be addressed are: (1) clarity of service personnel, (2) the discipline of service personnel, (3) responsibility for care workers; (4) the speed of service, (5) the ability of officers services, (6) obtain justice services, and (7) the courtesy and hospitality workers.

scholarly journals Network robustness improvement via long-range links

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Vincenza Carchiolo ◽  
Marco Grassia ◽  
Alessandro Longheu ◽  
Michele Malgeri ◽  
Giuseppe Mangioni
Keyword(s):  
Complex Networks ◽  
Long Range ◽  
Real World ◽  
Network Robustness ◽  
Scale Free ◽  
Area Of Interest ◽  
Before And After ◽  
Significant Area ◽  
Better Than

AbstractMany systems are today modelled as complex networks, since this representation has been proven being an effective approach for understanding and controlling many real-world phenomena. A significant area of interest and research is that of networks robustness, which aims to explore to what extent a network keeps working when failures occur in its structure and how disruptions can be avoided. In this paper, we introduce the idea of exploiting long-range links to improve the robustness of Scale-Free (SF) networks. Several experiments are carried out by attacking the networks before and after the addition of links between the farthest nodes, and the results show that this approach effectively improves the SF network correct functionalities better than other commonly used strategies.

scholarly journals Six ultraviolet minutes for cleaner operating theatres

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
R Bosco ◽  
S Gambelli ◽  
V Urbano ◽  
G Cevenini ◽  
G Messina
Keyword(s):  
Cross Sectional Study ◽  
Cross Sectional ◽  
Before And After ◽  
Operating Theatres ◽  
Cleaning Procedures ◽  
The Difference ◽  
Contamination Levels ◽  
Different Levels ◽  
Better Than ◽  
Final Cleaning

Abstract Background Sanitizing the operating theatres (OT) is important to minimize risk of post-operative infections. Disinfection procedures between one operation and another is less aggressive than final cleaning procedures, at the end of the day. Aim was assessing the difference of contamination: i) between different levels of disinfection; ii) before and after the use of a UVC Device (UVC-D). Methods Between December 2019/February 2020 a cross sectional study was conducted in OT in a real clinical context. 94 Petri dishes (PD) were used in 3 OT. Three different sanitation levels (SL1-3) were compared pre- and post-use of UVC-D: i) No cleaning after surgery (SL1); ii) after in-between cleaning (SL2); iii) after terminal cleaning (SL3). UVC-D was employed for 6 minutes, 3 minutes per bed side. PD were incubated at 36 °C and colony forming unit (CFU) counted at 48h. Descriptive statistic, Wilcoxon and Mann-Whitney tests were performed to assess the contamination levels in total, pre/post use of UVC-D, and between different sanitation levels, respectively. Results In total we had a mean of 3.39 CFU/PD (C.I. 2.05 - 4.74) and a median of 1 CFU/PD (Min. 0 - Max. 39), after UVC-D use we had a mean of 2.20 CFU/PD (C.I. 0.69 - 5.09) and a median of 0 CFU/PD (Min. 0 - Max. 133). The UVC-D led to a significant reduction of CFU (p < 0.001). Without UVC-D we had a significant CFU drop (p < 0.05) between SL1 and SL3. Using UVC-D, we observed significant reductions of contamination (p < 0.05) between SL3 and SL1. Comparing SL1 (median 0) post UVC-D use vs SL2 pre UVC-D use (median 0.5), and SL2 post UVC-D use (median 0) vs SL3 pre UVC-D use (median 1) we had a significant reduction of contamination (p < 0.05). Conclusions UVC-D improved environmental contamination in any of the three sanitation levels. Furthermore, the use of UVC-D alone was better than in-between and terminal cleaning. Although these encouraging results, the cleaning procedures executed by dedicated staff has to be considered. Key messages UVC are efficient to decrease contamination in operating theatres regardless of sanitation levels. The additional use of UVC technology to standard cleaning procedures significantly improves sanitation levels.

Relation of blood-free to blood-inclusive postmortem lung water measurements in sheep

1985 ◽  
Vol 59 (2) ◽  
pp. 592-596 ◽  
Author(s):  
J. C. Collins ◽  
J. H. Newman ◽  
N. E. Wickersham ◽  
W. K. Vaughn ◽  
J. R. Snapper ◽  
...  
Keyword(s):  
Extravascular Lung Water ◽  
Weight Ratio ◽  
Lung Homogenate ◽  
Lung Water ◽  
Before And After ◽  
The Mean ◽  
Space Expansion ◽  
Highly Correlated ◽  
Linear Regressions ◽  
Better Than

Our purpose was to see if the postmortem weight ratio of extravascular lung water to blood-free dry lung (blood-free ratio) was related to similar ratios in blood-inclusive lung and in blood. We developed linear regressions of blood-free ratio on ratios for blood-inclusive lung and blood together and for blood-inclusive lung alone for 73 sheep studied under 11 different protocols and for two subgroups of sheep, one with plasma space expansion and the other without expansion. The relation of ratios of blood-free to blood-inclusive lungs was different between the two subgroups. Although all regressions were highly correlated, the fits of the blood-free ratio on ratios for blood-inclusive lung and blood together were better than for blood-inclusive lung alone. The mean error of prediction of extravascular lung water for all sheep was significantly less for the regression of blood-free ratio on ratios for blood and blood-inclusive lung together (11 g) than for blood-inclusive lung alone (18 g). This study shows that weights of lung homogenate and blood samples before and after simple oven drying can be used to provide accurate inexpensive estimates of postmortem extravascular lung water.

Effect of Double Freezing and Subsequent Long-Term Refrozen Storage at −23 °C on the Quality of Inshore Male Capelin (Mallotus villosus)

1978 ◽  
Vol 35 (4) ◽  
pp. 452-456 ◽  
Author(s):  
J. R. Botta ◽  
D. H. Shaw
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Peroxide Value ◽  
Storage Time ◽  
Mallotus Villosus ◽  
Protein Nitrogen ◽  
Capelin Mallotus Villosus ◽  
Extractable Protein

Whole inshore male capelin (Mallotus villosus) were stored at −23 °C for 2 mo (C2), or 6 mo (C6) prior to thawing, beheading and eviscerating, and refreezing. Though the quality of the twice-frozen product was in both cases inferior to a once-frozen sample, it was still quite acceptable after 2 yr of refrozen storage. As expected, quality was superior in the C2 samples, but in both sets of samples taste deteriorated to a greater extent than texture. Chemical measurement of peroxide value indicated a possible development of rancidity that could not be detected by sensory analysis. Considerable lipid hydrolysis occurred, with the free fatty acids (FFA) at least doubling during storage; increases were greater in C6. In both experiments FFA production correlated with texture, taste, and with extractable protein nitrogen (EPN). Dimethylamine (DMA), trimethylamine (TMA), hypoxanthine, and EPN appeared to be good indicators of storage time and sensory quality. Key words: capelin, dimethylamine (DMA), extractable protein nitrogen (EPN), free fatty acids (FFA), hypoxanthine, peroxide value, refrozen storage, taste, texture, trimethylamine

scholarly journals The effectiveness of integrating existing digital learning resources into classroom teaching – an evaluation of the learning achievement

2012 ◽  
Vol 8 (2) ◽  
pp. 150-161
Author(s):  
Svava Pétursdóttir
Keyword(s):  
Secondary Science ◽  
Learning Resources ◽  
Teacher Competence ◽  
Digital Learning ◽  
Science Classrooms ◽  
Before And After ◽  
Quasi Experimental ◽  
Digital Learning Resources ◽  
Selection Of ◽  
Better Than

This paper presents the results of an intervention study exploring the effectiveness of an implementation of a selection of digital learning resources (DLR) in lower secondary science classrooms. Eight teachers participated in a quasi-experimental intervention, teaching three different subjects with and without DLRs. The data presented are from pupil tests before and after the teaching combined with observation of lessons and interviews with both pupils and teachers. In two of the three subjects the groups using DLRs did slightly better than the comparison group. The results indicate that successful ICT based learning is just as dependent on teacher competence as the quality and features of the resources.

scholarly journals Surveys of larval sealworm (Pseudoterranova decipiens) infection in various fish species sampled from Nova Scotian waters between 1988 and 1996, with an assessment of examination procedures

2001 ◽  
Vol 3 ◽  
pp. 57 ◽  
Author(s):  
G McClelland ◽  
DJ Martell
Keyword(s):  
Gadus Morhua ◽  
Gulf Of Maine ◽  
New Host ◽  
Pseudoterranova Decipiens ◽  
Infection Parameters ◽  
Routine Inspection ◽  
Frozen Fish ◽  
Nova Scotian ◽  
New Host Records ◽  
Benthic Consumers

Between November 1988 and October 1996, >10,000 fish from the Breton Shelf, Sable Island Bank and the northeastern Gulf of Maine were examined for larval anisakines. Larval sealworm, Pseudoterranova decipiens, occurred in 30 of 39 species surveyed, including 8 new host records, Enchelyopus cimbrius, Lycodes reticulatus, Eumesogrammus praecisus, Lumpenus lumpretaeformis, Lumpenus maculatus, Cryptacanthodes maculatus, Artediellus atlanticus and Triglops murrayi. The parasite was most prevalent and abundant in mature demersal piscivores and benthic consumers. Sealworm densities (nr kg-1 host wt.), however, were greatest in small benthophagous fish including mature E. cimbrius, A. atlanticus, T. murrayi and Aspidophoroides monopterygius, and juvenile Hippoglossoides platessoides. ANOVA revealed that geographical disparities in sealworm prevalence and abundance were highly significant in 14 of 20 species tested, although significant disparities between samples from each of the three areas were evident only in H. platessoides. Almost invariably, infection parameters were greatest in fish from Sable Island Bank. ANOVA also indicated that sealworm prevalence and/or abundance increased significantly in Sable Island Bank populations of Gadus morhua, H. platessoides, and seven other species between 1985-1986 and 1989-1990. Routine examinations, in which host flesh was sliced and candled, proved as efficacious as digestion in warm (35° C) pepsin-HCl for detection of larval sealworm in the flesh of large frozen fish. Procedures employing fresh (iced) samples, digestion at ambient temperature and microscopy are recommended, however, for surveys of small benthic consumers. Many of the sealworm infecting the latter hosts are tiny (2 to 10 mm in length) nematodes, which escape detection by routine inspection, and may not survive in warm pepsin-HCl solution.

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