A study was carried out to evaluate temperature variation and quality deterioration of packaged cod fillets as influenced by the box type used and their position on pallets under dynamic temperature storage. Storage life of thermally abused fillets was compared to that of fillets stored at steady temperature. Thermal performance of fish boxes, made of corrugated plastic on one hand and expanded polystyrene on the other hand, was also compared. Fillet temperature at multiple positions on the pallets along with environmental temperature and humidity were monitored during storage. Differences in product temperature of up to 10.5 ° C were recorded on the thermally abused pallets stored for 6.4 h at mean ambient temperature of 18.5 ° C. A reduction in storage life of 1.5–3 days was observed depending on the box position on the abused pallets compared to steady temperature storage.
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A mathematical model for heat transfer from surrounding environment to a single food package is developed. A simplified analytical solution for three-dimensional (3D) unsteady temperature distribution in the food package with rectangular geometry taking into account the ambient temperature is obtained. The model is developed to be used as an efficient tool for estimating the effects of temperature abuse on the food product inside a single packaging unit. The food product is considered to be a homogenous solid body. The packaging material and air inside the package are modeled using an effective heat transfer coefficient. The developed model is validated by a comparison with experimental results obtained for fresh haddock fillets in expanded polystyrene (EPS) boxes exposed to temperature abuse and by comparison with numerical results obtained by the commercial software FLUENT. A satisfactory agreement was obtained between the experimental and numerical results.
Temperature variations in cod fillets packaged in four levels of EPS boxes stored on pallets under thermal load were studied numerically and experimentally. In the experiment the fillet temperature along with environmental temperature were monitored at 39 positions on the pallets during 9-h dynamic temperature storage between 7 and 23 ° C. A three-dimensional time-dependent heat transfer model was developed using the ANSYS FLUENT Computational Fluid Dynamics (CFD) software. The overall mean absolute error of the model was 0.3 ° C and the maximum error obtained at a single position over the whole period was 2.4 ° C. The model was further developed in order to simulate temperature evolution inside a fully loaded, 12-level pallet under the same dynamic temperature conditions as a four-level pallet studied before. The mean temperature after 9-h thermal load was 1.0 ° C lower in the 12-level pallet but the maximum temperature evolution was similar in both pallets. Finally, the model was used to investigate the temperature-maintaining effect of superchilling fish before the thermal load.
Fourteen new microsatellite loci were developed and tested on Atlantic herring Clupea harengus with 39 individuals from Iceland and 49 individuals from Norway. The microsatellites, which contain di, tri and tetranucleotide repeats, are polymorphic (7–30 alleles), with observed heterozygosity ranging between 0 · 69 and 1 · 00 and expected heterozygosity between 0 · 55 and 0 · 97.
Background / objectives: Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium.
Design: The subjects were 96 randomly selected girls, aged 16-20, who answered a validated food frequency questionnaire (FFQ) for dietary assessment. Selenium intake from each food group was calculated in mg / day. Blood samples were collected for measurement of whole blood selenium.
Results: Mean dietary selenium was 51 ± 25 mg / day. Milk / dairy products, including cheese, contributed 36 ± 14% of total dietary selenium; fish 18 ± 12%; and bread / cereal products 13 ± 6%. Mean whole blood selenium was 117 ± 12 μg / l (range 90-208); nearly 90% of subjects were above the optimal level of 100 µg / l. Fish and bread / cereal products were the only foods significantly correlated with selenium in blood (r = 0.32; P = 0.002 and r = 0.22; P = 0.04, respectively) while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake.
Conclusion: In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.
The North Atlantic fin whale (Balaenoptera physalus) undertakes long-distance annual migration between high-latitude summer feeding locations and low-latitude winter mating locations, like most of the baleen whales. By statistically comparing genotype profiles of mother-fetus pairs (n = 23) to that of the potential alleged father (n = 139) captured at the same feeding location in Iceland, we found a matching pairing of a mother-fetus captured in 2009 and a father captured in 2010. To our knowledge, the present study is the first one to detect a mother-fetus pair matching with an alleged father, caught at exactly the same feeding area one year later.
Temperature history from three air and three sea freights of fresh cod loins and haddock fillets in expanded polystyrene boxes from Iceland to the UK and France were analyzed to find out the effect of different factors on the temperature profile and predicted remaining shelf life (RSL) of the product. It was also aimed at pinpoint hazardous steps in the supply chains. Significant difference (P <0.001) was found in: the temperature at different locations inside a certain box; mean product temperature between boxes of a certain shipment; and the boxes' surface temperature at different positions on a pallet for the whole logistics period. The predicted RSL depends on the time and temperature history of the product, shortest for sea transportation and longest for an air shipment with precooled product. Several critical steps were found in air freighting: the flight itself, loading / unloading operations and holding storage at unchilled conditions.
Purpose
The evening meal is an important, regular event in the lives of many people and its daily practices lead consumers to develop habits that determine their food choices. The objective of the present work is to further investigate how consumers make choices by determining the stages as well as the content of the family's daily food (ie seafood and meat ‐ related) decision ‐ making process.
Design / methodology / approach
Twenty ‐ four families in Denmark, Norway and Iceland were asked to fill in a one ‐ to ‐ two ‐ week semi ‐ structured diary regarding any thoughts they had about the decision ‐ making sequence regarding their evening meals. Data were analyzed by means of content analysis so as to gain insight into the main themes and distinctive patterns with respect to the four stages of the decision ‐ making sequence by identifying a number of codes and sub ‐ codes of high and lower abstraction level.
Findings
The main results were similar across the three countries. Planning was the most important phase of the evening meal decision ‐ making sequence, where Nordic respondents considered practical issues, and engaged in a more rational type of thinking, allowing cognitive aspects to prevail at this particular stage. The presence of rational thoughts was repeated in the successive stages of purchasing, whereas affective thoughts were elicited mainly during the later stages of preparation and consumption. Furthermore, the comparison of seafood and meat as choices that complied with respondents' demands and expectations revealed that the two food types were perceived as substitutes for each other; however, meat was considered a choice that respondents felt more confident with in terms of pre ‐ and post ‐ purchasing experience.
Originality / value
This paper offers substantial insights into the factors that influence the decision making process, as well as the importance that consumers assign to those factors across most stages of the decision making process. This valuable, in ‐ depth information can only be collected by using qualitative methods such as the present diaries. Gaining insights into the factors that influence various stages of the evening meal decision ‐ making process enables researchers to identify the importance that consumers assign to cognitive and affective factors across the food provisioning stages for a variety of food products (including seafood).
Lipid oxidation and fishy odor development in protein hydrolyzate from fresh and ice-stored Nile tilapia (Oreochromis niloticus) were investigated. During iced storage of 18 days, heme iron content decreased with a concomitant increase in non-heme iron content (P <0.05). Peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) values increased. Phospholipid content decreased with a corresponding increase in free fatty acid content. The results suggested that lipid hydrolysis and oxidation took place during storage. When protein hydrolysates were produced from fresh and 18 days ice-stored Nile tilapia muscle, higher lipid oxidation and fishy odor / flavor along with higher amount volatile compounds were obtained in hydrolysate for unfresh sample (P <0.05). However, the addition of mixed antioxidants during hydrolysis process markedly lowered lipid oxidation, b∗, ΔC∗, ΔE∗ values, fishy odor / flavor as well as the formation of volatile compounds in the resulting hydrolysates prepared from both fresh and unfresh samples. Therefore, hydrolyzate from Nile tilapia muscle with reduced fishy odor and lighter color could be prepared by using fresh fish and incorporation of mixed antioxidants during hydrolysis.
Testosterone enanthate (TE) administration attenuates bone loss in orchiectomized (ORX) rats. However, testosterone administration may increase risk for prostate / lower urinary tract related adverse events and polycythemia in humans. Trenbolone enanthate (TREN) is a synthetic testosterone analogue that preserves bone mineral density (BMD) and results in less prostate enlargement than testosterone in young ORX rodents. The purpose of this experiment was to determine if intramuscular TREN administration attenuates bone loss and maintains bone strength, without increasing prostate mass or hemoglobin concentrations in skeletally mature ORX rodents. Forty, 10 month old male F344 / Brown Norway rats were randomized into SHAM, ORX, ORX + TE (7.0 mg / week), and ORX + TREN (1.0 mg / week) groups. Following surgery, animals recovered for 1 week and then received weekly: vehicle, TE, or TREN intramuscularly for 5 weeks. ORX reduced total and trabecular (t) BMD at the distal femoral metaphysis compared with SHAMs, while both TREN and TE completely prevented these reductions. TREN treatment also increased femoral neck strength by 28% compared with ORX animals (p <0.05), while TE did not alter femoral neck strength. In addition, TE nearly doubled prostate mass, compared with SHAMs (p <0.05). Conversely, TREN induced a non-significant 20% reduction in prostate mass compared with SHAMs, ultimately producing a prostate mass that was 64% below that found in ORX + TE animals (p <0.01). Hemoglobin concentrations and levator ani / bulbocavernosus (LABC) muscle mass were elevated in ORX + TE and ORX + TREN animals to a similar degree above both SHAM and ORX conditions (p <0.01). In skeletally mature rodents, both high-dose TE and low-dose TREN completely prevented the ORX-induced loss of tBMD at the distal femoral metaphysis and increased LABC mass. TREN also augmented femoral neck strength and maintained prostate mass at SHAM levels. These findings indicate that TREN may be an advantageous agent for future clinical trials evaluating agents capable of preventing bone loss resulting from androgen deficiency.