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Evaluation of ptarmigan management with a population reconstruction model

The rock ptarmigan (Lagopus muta) is a popular game bird in Iceland, but the population has endured a long-term decline. A hunting ban was enforced in 2003, but 2 years later hunting was allowed again with added restrictions. The aim of this study was to investigate the effects of a change in hunting regulations on the ptarmigan population in northeast Iceland, 1998–2013, using a population reconstruction model and to estimate the abundance of juveniles and adults, natural survival, and harvest mortality. The estimated abundance at the beginning of the hunting season ranged from 42,000 (95% CI = 36,000–49,000) birds in 2002 to 158,000 (95% CI = 105,000–250,000) in 1998. The natural survival of adult rock ptarmigan was density dependent and ranged from 36% to 65% (95% CI = 30–75%). Survival for juveniles was constant and was estimated to be 19% (95% CI = 18–20%). We included a change point in the model to account for a change in the harvest mortality that could have occurred with the changes in the hunting regulations. The results indicated that the change in hunting regulations did reduce ptarmigan harvest mortality and changed the harvest strategies of hunters. Inclusion of a change point in models is useful for managers to test if a change in regulations had an effect on the target population. © 2018 The Wildlife Society.

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Characterization of carotenoids in Rhodothermus marinus

Rhodothermus marinus, a marine aerobic thermophile, was first isolated from an intertidal hot spring in Iceland. In recent years, the R. marinus strain PRI 493 has been genetically modified, which opens up possibilities for targeted metabolic engineering of the species, such as of the carotenoid biosynthetic pathway. In this study, the carotenoids of the R. marinus type-strain DSM 4252T, strain DSM 4253, and strain PRI 493 were characterized. Bioreactor cultivations were used for pressurized liquid extraction and analyzed by ultra-high performance supercritical fluid chromatography with diode array and quadropole time-of-flight mass spectrometry detection (UHPSFC-DAD-QTOF/MS). Salinixanthin, a carotenoid originally found in Salinibacter ruber and previously detected in strain DSM 4253, was identified in all three R. marinus strains, both in the hydroxylated and nonhydroxylated form. Furthermore, an additional and structurally distinct carotenoid was detected in the three strains. MS/MS fragmentation implied that the mass difference between salinixanthin and the novel carotenoid structure corresponded to the absence of a 4-keto group on the ß-ionone ring. The study confirmed the lack of carotenoids for the strain SB-71 (ΔtrpBΔpurAcrtBI’::trpB) in which genes encoding two enzymes of the proposed pathway are partially deleted. Moreover, antioxidant capacity was detected in extracts of all the examined R. marinus strains and found to be 2–4 times lower for the knock-out strain SB-71. A gene cluster with 11 genes in two operons in the R. marinusDSM 4252T genome was identified and analyzed, in which several genes were matched with carotenoid biosynthetic pathway genes in other organisms.

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Effects of controlled thawing media temperatures on quality and safety of pre-rigor frozen Atlantic cod (Gadus morhua)

Novel strategies for thawing of pre-rigor frozen Atlantic cod (Gadus morhua) in water with air circulation, applying different and controlled temperatures are presented. After thawing (day 0) and after six days of storage at 2.9 ± 0.6 °C (day 6), quality parameters (thawing- and drip loss, cooking yield, sensory evaluation, and textural properties), chemical (pH, water content, total volatile basic nitrogen (TVB-N)) and microbiological analyses (total viable counts (TVC-IA), H2S-producing bacteria (H2S-IA), coliforms, thermo-tolerant coliforms and presumptive E. coli, and Listeria monocytogenes) were performed. The results obtained were compared statistically. Both thawing strategies, thawing at 10 °C and −0.5 °C or at constant 10 °C, preserved good quality fish. The hygienic conditions during the thawing processes were satisfactory and there were no indications of impaired food safety during any of the thawing strategies. No pathogens were detected in any of the cod samples, nor in the thawing media. The results showed that water thawing at −0.5 to 10 °C is suitable for frozen cod, without compromising quality and safety, and that no significant difference were seen between the selected thawing temperature regimes.

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A comparative study of quality and safety of Atlantic cod (Gadus morhua) fillets during cold storage, as affected by different thawing methods of pre-rigor frozen headed and gutted fish

Background: The catch of marine whitefish is typically seasonal, whereas the land based processing industry has a need for all-year stable supply of raw materials. This challenge can be met by applying fish frozen at sea. When using frozen fish the methods employed for thawing may influence the safety and quality of the final product. This study aimed to investigate the applicability of novel thawing strategies in order to provide an all-year supply of high-quality and safe cod products. Results: Comparative investigations of quality and safety factors after thawing in water, with and without air circulation, and contact thawing were performed. The parameters included water-holding capacity, thawing loss, drip loss, cooking yield, sensory evaluation and microbiological analysis (including TVB-N). Water thawing with air circulation provided faster thawing compared to water thawing without air circulation and contact thawing. For all three methods, the quality of the thawed fish was acceptable and the shelf life of the fillets during chilled storage was between 10 and 14 days post-filleting. Conclusion: The results shows that controlled freezing of cod, followed by appropriate thawing may provide the processing industry with an all-year delivery of raw materials, without compromising quality and safety of the final product.

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Quality management framework for Total Diet Study Centres in Europe

A Quality Management Framework to improve quality and harmonization of Total Diet Study practices in Europe was developed within the TDS-Exposure Project. Seventeen processes were identified and hazards, Critical Control Points and associated preventive and corrective measures described. The Total Diet Study process was summarized in a flowchart divided into planning and practical (sample collection, preparation and analysis; risk assessment analysis and publication) phases. Standard Operating Procedures were developed and implemented in pilot studies in five organizations. The flowchart was used to develop a quality framework for Total Diet Studies that could be included in formal quality management systems. Pilot studies operated by four project partners were visited by project assessors who reviewed implementation of the proposed framework and identified areas that could be improved. The quality framework developed can be the starting point for any Total Diet Study centre and can be used within existing formal quality management approaches.

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DNA barcoding revealing mislabeling of seafood in European mass caterings

Seafood is amongst the most internationally traded food commodities worldwide and it is one of the food groups most likely to be subject to fraud. A number of studies have been conducted where samples from retail-, restaurant- and food service outlets have been tested for species substitution. These studies have mostly focused on specific species, particular types of outlets or confined to some geographical location. The study presented in this paper is the first large-scale attempt to study the rate of fish mislabeling in mass caterer (HoReCa) sector across Europe. A total of 283 samples were collected in 180 mass caterer outlets in 23 European countries. DNA barcoding revealed that 26% of the samples were mislabeled and that 31% of the outlets sold mislabeled seafood. The highest mislabeling rate was observed in Spain, Iceland, Finland and Germany, where close to 50% of the outlets sampled offered mislabeled seafood. Conversely, there was no mislabeling detected in Sweden, Switzerland and Slovakia. The species with the highest mislabeling rates were dusky grouper, butterfish, pike perch, sole, bluefin tuna and yellowfin tuna. In the case of other important fish species in Europe such as hake, cod, haddock and swordfish, mislabeling rates ranged between 14 and 33%. The results of the study show that the majority of the mislabelings are with cheaper fish, such as the presence of Pangasius commonly substituting other species, being labeled as more expensive ones, suggesting economic motivation for mislabelling.

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The myth of the poor fisher: Evidence from the Nordic countries

Fishers are often perceived to be poor, and low income levels are used to justify subsidies and other types of direct and indirect income support to maintain coastal communities. In this study fishers’ income levels are investigated in four Nordic countries; Denmark, Iceland, Norway and Sweden for different types of fishers and vessels and in comparison to alternative occupations. The most important result is that fishers in these countries are doing relatively well, and only in Sweden is the fishers’ average income level below the average national income. Within the fleets, there are substantial differences. Owners of coastal vessels tend to have the lowest income, and also lower than crews. Owners as well as crews on larger vessels tend to do much better and in the largest fishing nations, Iceland and Norway, they do especially well.

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A framework for results‐based management in fisheries

We present a framework for results-based management (RBM) of commercial fisheries. The core idea of RBM is to reduce micromanagement by delegating management responsibility to resource users. The RBM framework represents an industrial organization approach to co-management and comprises three defining processes, conducted by three independent “agents”: (i) an “authority” defines specific and measurable and achievable objectives (outcome targets, OTs) for the utilization of fisheries resources, (ii) resource user organizations (termed “operators”) take responsibility for achieving these OTs and provide documentation that (iii) allows independent “auditors” to evaluate the achievement of OTs. Using incentive mechanisms, notably deregulation, RBM grants operators the flexibility to develop and implement innovative and cost-effective ways to achieve OTs. The feasibility of implementing RBM in five European fisheries was investigated in cooperation with relevant stakeholders through artificial planning processes and computer simulations. The operators involved were enthusiastic, and new management plans were drafted based on the framework. These included socioeconomic OTs in addition to traditional stock objectives, encompassing an ecosystem approach. Several issues are in need of further research to consolidate the approach and prepare the ground for practical implementation, including: the specification of the legal and regulatory framework required to underpin RBM, details of transitional arrangements when shifting towards RBM (including cost-sharing) and the development of necessary organizational capacity for operators. Initially, we therefore envisage the framework being applied to high-value single-species fisheries, with a limited number of participants, which are adequately represented by a competent organization.

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Food, Nutrition, and Health in Iceland in Nutritional and Health Aspects of Food in Nordic Countries

Nutritional and Health Aspects of Food in Nordic Countries provides an analysis of traditional and ethnic foods from the Nordic countries, including Norway (and Svalbard), Sweden, Finland, Iceland, and Denmark (including Greenland and the Faroe Islands). The book addresses the history of use, origin, composition and preparation, ingredient origin, nutritional aspects, and the effects on health for various foods and food products in each of these countries. In addition, readers will find local and international regulations and suggestions on how to harmonize regulations to promote global availability of these foods.

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Food in the bioeconomy

Ensuring food security and food safety in a future facing the foreseen grand global challenges will be challenging, where they at the same time open up a wealth of opportunities. Further advancing the bioeconomy is a key tool to tackle these very complex challenges and at the same time lead to sustainable economic growth. Significant changes and different approaches are needed to meet the needs and demands of our future consumers. The next big wave of technological disruptions will be in the new bioeconomy, most notably the food industry. The development of new technologies cannot compromise food security and safety but, on the contrary, should be aimed at increasing both. To succeed in this changing environment and tackle all the grand global challenges, we need to be unafraid to think in very different ways than we have before. We need to understand the market and the consumers and where they are heading, find new innovative solutions and work across sectors with partners we never imagined working with before.

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