Category: Branches

The distribution and characteristics of water in the muscle of various commercially available Icelandic heavily salted Atlantic cod products were analyzed with proton magnetic resonance methods. The products varied in choice of catching method, in pre- or post-rigor processing, flattening or filleting cut, and pre-salting technique (brine injection with salt with / without polyphosphates, brining and pickling) and choice of brine-injection instruments.

All products had heterogeneous water distributions, but the level of heterogeneity was dependent on the handling during processing. Brine injection led to salt-induced swelling, which effect remained after the kench dry salting step. Double brine injection induced needle traces in the muscle, even after kench salting. Relaxation time analysis indicated that pickle salted products had the highest degree of protein denaturation in the muscle amongst the analyzed pre-salting methods. The multi-parametric analysis indicated how powerful the MR methods are for process and product characterization and optimization.

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Fast and non-destructive prediction of the quality characteristics of food products during frozen storage are of great value both for the food industry and the consumers. The current study investigated the potential of using low field Nuclear Magnetic Resonance (NMR) along with multivariate chemometric methods to predict various important physicochemical quality parameters in Atlantic mackerel during frozen storage, as affected by season of catch, freezing method and temperature, as well as frozen storage duration. The obtained results clearly showed that transverse relaxation data obtained by low field NMR can be effectively used to simultaneously predict multiple quality characteristics of the mackerel fillets through storage, including water and lipid content, water holding capacity, lipid oxidation (peroxide value (PV), and thiobartituric reactive substances (TBARS)) and lipid hydrolysis (free fatty acids (FFA)) content within the muscle. The NMR data could furthermore be used to predict variations in the muscle due to season of catch, the frozen storage duration of the mackerel samples when all samples were used, and whether the fish had been headed and gutted or stored whole, which freezing equipment had been used, and the frozen storage temperature for mackerel samples caught at the end of July. Simplified monitoring and optimization of these quality parameters in frozen mackerel with a fast and non-destructive analytical technique like low field NMR is thus of great value for the fishing industry

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Marine Synechococcus cyanobacteria are major contributors to global oceanic primary production and exhibit a unique diversity of photosynthetic pigments, allowing them to exploit a wide range of light niches. However, the relationship between pigment content and niche partitioning has remained largely undetermined due to the lack of a single-genetic marker resolving all pigment types (PTs). Here, we developed and employed a robust method based on three distinct marker genes (cpcBA, mpeBA, and mpeW) to estimate the relative abundance of all known Synechococcus PTs from metagenomes. Analysis of the Tara Oceans dataset allowed us to reveal the global distribution of Synechococcus PTs and to define their environmental niches. Green-light specialists (PT 3a) dominated in warm, green equatorial waters, whereas blue-light specialists (PT 3c) were particularly abundant in oligotrophic areas. Type IV chromatic acclimaters (CA4-A / B), which are able to dynamically modify their light absorption properties to maximally absorb green or blue light, were unexpectedly the most abundant PT in our dataset and predominated at depth and high latitudes. We also identified populations in which CA4 might be nonfunctional due to the lack of specific CA4 genes, notably in warm high-nutrient low-chlorophyll areas. Major ecotypes within clades I – IV and CRD1 were preferentially associated with a particular PT, while others exhibited a wide range of PTs. Altogether, this study provides important insights into the ecology of Synechococcus and highlights the complex interactions between vertical phylogeny, pigmentation, and environmental parameters that shape Synechococcus community structure and evolution.

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Atlantic salmon (Salmo salar L.) populations from different river origins mix in the North Atlantic during the marine life stage. To facilitate marine stock identification, we developed a genetic baseline covering the European component of the species' range excluding the Baltic Sea, from the Russian River Megra in the north-east, the Icelandic Ellidaar in the west, and the Spanish Ulla in the south , spanning 3737 km North to South and 2717 km East to West. The baseline encompasses data for 14 microsatellites for 26,822 individual fish from 13 countries, 282 rivers, and 467 sampling sites. A hierarchy of regional genetic assignment units was defined using a combination of distance-based and Bayesian clustering. At the top level, three assignment units were identified comprising northern, southern, and Icelandic regions. A second assignment level was also defined, comprising eighteen and twenty-nine regional units for accurate individual assignment and mixed stock estimates respectively. The baseline provides the most comprehensive geographical coverage for an Atlantic salmon genetic data-set, and a unique resource for the conservation and management of the species in Europe. It is freely available to researchers to facilitate identification of the natal origin of European salmon.

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Food safety is embedded in food-related problems, and in proposed solutions. Despite continuous investment, the WHO estimates 23 million cases of foodborne illness and 5000 deaths in Europe every year and Europeans are not confident in the food system. Now, the circular economy aims to improve global food security through sustainable production, thus new ingredients, methods and food safety challenges. Food is unequivocally linked to non-communicable diseases, and changes are needed for nutritional food safety. Emerging and re-emerging foodborne pathogens are changing the epidemiology of foodborne diseases. Additionally, some chemicals are of concern, and food is a major source of human exposure. Finally, risk communication is required for management of consumer-based foodborne hazards, yet this foodborne illness is common. We ignore food safety challenges at our peril as potential consequences of a lapse are huge; keeping the food supply safe is a never-ending task.

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Background

The continuous high expectations on the world's fisheries to provide products for human consumption is leading to increased overexploitation of fishing stocks. This unsustainable exploitation desperately calls for other suitable resources that can relieve the pressure on the fisheries. The utilization of Calanus finmarchicus has been proposed as a suitable alternative. There is, however, still a question of both ecological and economic sustainability of such exploitation.

Scope and approach

This review describes currently utilized marine resources, and compares the suitability of C. finmarchicus as a useful alternative for those resources. Additionally, the review describes the life history and chemical composition of C. finmarchicus. Current utilization of C. finmarchicus is also described, along with industrial methods used to derive various products from Calanus, as well as a discussion of other potential products from the resource.

Key findings and conclusions

C. finmarchicus can potentially be considered an alternative marine resource as it has a unique lipid composition, is rich in antioxidants, and contains various enzymes. However, the question of sustainable catching remains unanswered and must be addressed before C. finmarchicus can be considered for utilization.

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SeaBioTech is a 48-month project designed and driven by SMEs to create innovative marine biodiscovery pipelines as a means to convert the potential of marine biotechnology into novel industrial products for the pharmaceutical (human and aquaculture), cosmetic, functional food and industrial chemistry sectors. SeaBioTech will reduce barriers to successful industrial exploitation of marine biodiversity for companies more accustomed to 'terrestrial' biotechnology. SeaBioTech directly addresses five key challenges to remove bottlenecks in the marine biodiscovery pipeline, leading to (1) improvements in the quality of marine resources available for biotechnological exploitation, (2) improvement in technical aspects of the biodiscovery pipeline to shorten time to market, and (3) developing sustainable modes of supply of raw materials for industry. The two last challenges center on enabling activities to enhance the marine biodiscovery process: first, clarification of legal aspects to facilitate access to marine resources, their sustainable use, and their secure exploitation; second, to create an improved framework for access to marine biotechnology data and research materials. To achieve its goals, SeaBioTech brings together complementary and world-leading experts, integrating biology, genomics, natural product chemistry, bioactivity testing, industrial bioprocessing, legal aspects, market analysis and knowledge exchange. The expertise assembled within the consortium reflects the industry-defined needs, from the SME partners' initial definition of market and product opportunities to their ultimate proof-of-concept demonstration activities. SeaBioTech will have significant impact on research and technology, on innovation, on European competitiveness and on economic growth. It will provide a model to accelerate the development of European biotechnology into a world leading position.

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Fishmeal replacement with a mixture of plant protein (PP) raw materials (soy, wheat gluten meal, corn gluten meal and rapeseed meal) in diets for 300-950 g turbot was tested. Eight different diets with fishmeal protein stepwise varying from 53.7% of crude protein (CP) to 93% of CP of the total protein in the diet were tested. The fish was weighed at monthly intervals for following weight development and calculation of specific growth rates, daily feed intake and feed conversion ratio. At the end of the experiment, fish was sampled for sensory evaluation. Average final weight was 950 g and did not vary between the experimental groups. There were no effects of dietary treatment on specific growth rates, daily feed intake, feed conversion ratio or sensory attributes measured. The least-cost diet (with 53.7% fishmeal protein) is about 12% lower in raw material cost (based on material price of diet components) than the all fishmeal diet. The results therefore indicate that the raw material cost in feed for on-growing turbot can be reduced considerably without any negative effect on growth and feed utilization.

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An interlaboratory study of five laboratories testing real-time polymerase chain reaction (PCR) with TaqMan probe detection of black seabream (Spondyliosoma cantharus) fish is presented in this work. The method is oriented to the intron of the nuclear gene encoding the main protein of the musculature of the fish, parvalbumin. This feature distinguishes the employed approach from those based on mitochondrial genes. Here, the intron is flanked by exon stretches highly conserved among species. This provides a unique advantage when a new fish species emerges as a commodity on the market: Species-versatile degenerate primers can be easily designed on these conserved exon stretches. Therefore, the initial uncertainty of the species-specific sequence of the intron can, in such case, be bypassed during the adoption of the method to this particular new species, because the amplicon obtained at this pilot stage provides the sequence of the intron itself. DNA isolates from eight specimens of S. cantharus and from nineteen other fish species, the latter being used as negative controls, were tested in this study by participating laboratories. The readouts in qualitative assessment were 100% accurate. The quantitative results provided an average value and variation among samples representing particular examples of S. cantharus

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