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Sigurjon Arason - One of the best experts on this subject based on the ideXlab platform.

  • Effect of thermal treatment and frozen storage on lipid decomposition of light and dark muscles of saithe (Pollachius virens).
    Food chemistry, 2014
    Co-Authors: Magnea G. Karlsdóttir, Kolbrun Sveinsdottir, Hordur G. Kristinsson, Dominique Villot, Brian D. Craft, Sigurjon Arason
    Abstract:

    Abstract Lipid decomposition of saithe ( Pollachius virens ) light and dark muscles was monitored during frozen storage at − 25 °C of raw (up to 18 months) and cooked products. Samples were cooked after 0, 6 and 12 months raw storage then refrozen and stored at −25 °C for 12 months to determine the stability of cooked-then-stored samples. Fatty acid profiles, formation of hydroperoxides (PV), thiobarbituric acid reactive substances (TBARS), fluorescence compounds (OFR) and free fatty acids (FFA) were evaluated throughout the storage for all samples. In general, results indicated that enzymatic lipolysis was the driving factor influencing the quality of saithe over raw storage and it mostly affected polyunsaturated lipids in the light muscle. Cooking, however, inhibited FFA formation and induced formation of PV and TBARS. This behavior was more evident in samples cooked after long raw storage periods. The initial quality of the raw material before cooking is therefore critical with regard to oxidative stability of cooked fish products.

  • Effects of temperature during frozen storage on lipid deterioration of saithe (Pollachius virens) and hoki (Macruronus novaezelandiae) muscles
    Food chemistry, 2014
    Co-Authors: Magnea G. Karlsdóttir, Kolbrun Sveinsdottir, Hordur G. Kristinsson, Dominique Villot, Brian D. Craft, Sigurjon Arason
    Abstract:

    Abstract Lipid deterioration of two lean fish species, saithe ( Pollachius virens ) and hoki ( Macruronus novaezelandiae ), during frozen storage at −20 and −30 °C (up to 18 months) was studied. Lipid composition, lipid oxidation and hydrolysis, and sensory attributes were evaluated on both light and dark muscles of the fish species. Results showed significant lipid deterioration with extended storage time, but lower storage temperature showed significantly more preservative effects. A marked difference was observed between the composition of dark muscle of hoki and saithe. Polyunsaturated fatty acids were the predominant lipids in dark muscle of saithe, while monounsaturated fatty acids were predominant in dark muscle of hoki. Further, the hydrolytic activity differed greatly between dark muscle of hoki and saithe, with significantly lower activity observed in hoki. Present results indicate that both tertiary lipid oxidation and hydrolysis products are appropriate for assessing lipid deterioration of saithe and hoki light muscle during frozen storage.

  • Injection of fish protein solutions of fresh saithe (Pollachius virens) fillets studied by low field Nuclear Magnetic Resonance and physicochemical measurements
    Journal of Food Science and Technology, 2013
    Co-Authors: María Gudjónsdóttir, Sigurjon Arason, Magnea Gudrún Karlsdóttir, Turid Rustad
    Abstract:

    Low field Nuclear Magnetic Resonance was used in comparison to yield and physicochemical measurements to assess the effects of salt and protein injection on the properties of saithe ( Pollachius virens ) fillets during chilled and frozen storage. Saithe fillets injected with various combinations of salt, homogenized fish proteins, gelatine and fish protein hydrolyzate, were compared to the properties of untreated fillets. Addition of salt or fish protein hydrolyzate resulted in increased yield after cooking and water holding capacity compared to other treatments. Transversal relaxation data fitting resulted in three water populations with relaxation times of 27–45 ms, 60–99 ms and 187–341 ms. Relaxation times and respective populations showed significant correlation to various physicochemical properties, that muscle water behaviour was changed by salt and protein injection and indicated protein denaturation during frozen storage. Fish protein hydrolyzate injected fillets were most stable through storage, while gelatine injected fillets were most denatured during frozen storage.

  • characteristics of freeze dried fish protein isolated from saithe Pollachius virens
    Journal of Food Science and Technology-mysore, 2012
    Co-Authors: Gholam Reza Shaviklo, Sigurjon Arason, Gudjon Thorkelsson, Kolbrun Sveinsdottir
    Abstract:

    Fish proteins isolated from by-products or low commercial/underutilized species using pH-shift process is a new source of proteins that may be used as wet or dried ingredients to develop value-added convenience foods. This paper reports the effects of freeze-drying on characteristics of fish protein isolates (FPI) from saithe (Pollachius virens) with or without lyoprotectants. Freeze-dried saithe mince from the same lot and without additives was used as a control. The resulting fish protein powders contained 71-93% protein, 1.5-3% moisture, 0-21% carbohydrate and 0.5-2% fat. Lipid oxidation (assessed by TBARS) of FPI powder groups was higher than that of fish mince powder. The results revealed that oxidation started during the pH-shift process and was increased by freeze-drying. Functional properties and sensory attributes were influenced by the advanced oxidation. However, the mince powder was less oxidized and had higher functional properties such as water binding capacity, gel forming ability, emulsification, foaming properties and colour and lower sensory scores for rancid odour and flavour than the FPI powders. Further studies on how to prevent oxidation of fish flesh during pH-shift and drying processes are recommended.

  • The influence of additives and drying methods on quality attributes of fish protein powder made from saithe (Pollachius virens)
    Journal of the science of food and agriculture, 2010
    Co-Authors: Gholam Reza Shaviklo, Sigurjon Arason, Gudjon Thorkelsson, Hordur G. Kristinsson, Kolbrun Sveinsdottir
    Abstract:

    BACKGROUND: Fish protein powder (FPP) is used in the food industry for developing formulated food products. This study investigates the feasibility of increasing the value of saithe (Pollachius virens) by producing a functional FPP. Quality attributes of spray and freeze-dried saithe surimi containing lyoprotectants were studied. A freeze-dried saithe surimi without lyoprotectants was also prepared as a control sample. RESULTS: The amount of protein, moisture, fat and carbohydrate in the FPPs were 745–928, 39–58, 21–32 and 10–151 g kg−1. Quality attributes of FPPs were influenced by the two drying methods and lyoprotectants. The highest level of lipid oxidation was found in the control and the second highest in the spray-dried FPP. The spray-dried fish protein had the lowest viscosity among all FPPs. Gel-forming ability of samples with lyoprotectants was higher than that of the control. Water-binding capacity, emulsion properties and solubility of the freeze-dried fish protein containing lyoprotectants were significantly higher than spray-dried and control samples. However, functional properties of spray-dried FPP were higher than the control sample. CONCLUSION: It is feasible to develop value-added FPP from saithe surimi using spray- and freeze-drying processes, but freeze-dried FPP containing lyoprotectant had superior functional properties and stability compared with spray-dried sample. Both products might be used as functional protein ingredients in various food systems. Copyright © 2010 Society of Chemical Industry

Ingebrit Uglem - One of the best experts on this subject based on the ideXlab platform.

  • A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations
    Journal of agricultural and food chemistry, 2015
    Co-Authors: Frutos Carlos Marhuenda Egea, Kilian Toledo-guedes, Pablo Sanchez-jerez, Ingebrit Uglem, Ricardo Ibanco-cañete, Bjørn-steinar Saether
    Abstract:

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites.

  • Assessing the Influence of Salmon Farming through Total Lipids, Fatty Acids, and Trace Elements in the Liver and Muscle of Wild Saithe Pollachius virens
    Marine and Coastal Fisheries, 2015
    Co-Authors: Pablo Arechavala-lopez, Pablo Sanchez-jerez, Bjørn-steinar Saether, Frutos C. Marhuenda-egea, Ingebrit Uglem
    Abstract:

    Saithe Pollachius virens are attracted to uneaten salmon feed underneath cages at open-cage salmon farms in Norway. The aggregated Saithe have modified their feeding habits as they have switched from wild prey to uneaten food pellets, which could lead to physiological and biochemical changes in the Saithe. Variations in profiles of total lipids, fatty acids, and trace elements in Saithe liver and muscle were measured to evaluate the influence of fish feed from salmon farms on wild Saithe populations. Farm-aggregated Saithe had higher fat content in liver tissues than did individuals captured more than 25 km away from farms, but no clear differences were found in muscle tissues. High proportions of fatty acids of terrestrial origin, such as oleic, linoleic, and linolenic acids, in liver and muscle tissues of farm-aggregated Saithe reflected the presence of wild Saithe at farms. Accordingly, low proportions of arachidonic, eicosapentaenoic, and docosahexaenoic acids in Saithe tissues mirrored the feeding activity at farms. Variations in specific trace element signatures among fish groups also revealed the farming influence on wild Saithe. High levels of Fe, As, Se, Zn, and B in liver, but also As, B, Li, Hg, and Sr in muscle of Saithe captured away from farms indicated the absence of feeding at farms.

  • A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations
    2015
    Co-Authors: Frutos Maruhenda C. Egea, Kilian Toledo-guedes, Pablo Sanchez-jerez, Ricardo Ibanco-cañete, Ingebrit Uglem, Bjørn-steinar Saether
    Abstract:

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites

Bjørn-steinar Saether - One of the best experts on this subject based on the ideXlab platform.

  • A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations
    Journal of agricultural and food chemistry, 2015
    Co-Authors: Frutos Carlos Marhuenda Egea, Kilian Toledo-guedes, Pablo Sanchez-jerez, Ingebrit Uglem, Ricardo Ibanco-cañete, Bjørn-steinar Saether
    Abstract:

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites.

  • Assessing the Influence of Salmon Farming through Total Lipids, Fatty Acids, and Trace Elements in the Liver and Muscle of Wild Saithe Pollachius virens
    Marine and Coastal Fisheries, 2015
    Co-Authors: Pablo Arechavala-lopez, Pablo Sanchez-jerez, Bjørn-steinar Saether, Frutos C. Marhuenda-egea, Ingebrit Uglem
    Abstract:

    Saithe Pollachius virens are attracted to uneaten salmon feed underneath cages at open-cage salmon farms in Norway. The aggregated Saithe have modified their feeding habits as they have switched from wild prey to uneaten food pellets, which could lead to physiological and biochemical changes in the Saithe. Variations in profiles of total lipids, fatty acids, and trace elements in Saithe liver and muscle were measured to evaluate the influence of fish feed from salmon farms on wild Saithe populations. Farm-aggregated Saithe had higher fat content in liver tissues than did individuals captured more than 25 km away from farms, but no clear differences were found in muscle tissues. High proportions of fatty acids of terrestrial origin, such as oleic, linoleic, and linolenic acids, in liver and muscle tissues of farm-aggregated Saithe reflected the presence of wild Saithe at farms. Accordingly, low proportions of arachidonic, eicosapentaenoic, and docosahexaenoic acids in Saithe tissues mirrored the feeding activity at farms. Variations in specific trace element signatures among fish groups also revealed the farming influence on wild Saithe. High levels of Fe, As, Se, Zn, and B in liver, but also As, B, Li, Hg, and Sr in muscle of Saithe captured away from farms indicated the absence of feeding at farms.

  • A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations
    2015
    Co-Authors: Frutos Maruhenda C. Egea, Kilian Toledo-guedes, Pablo Sanchez-jerez, Ricardo Ibanco-cañete, Ingebrit Uglem, Bjørn-steinar Saether
    Abstract:

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites

Fabienne Guérard - One of the best experts on this subject based on the ideXlab platform.

Uglem Ingebrigt - One of the best experts on this subject based on the ideXlab platform.

  • Does waste feed from salmon farming affect the quality of saithe (Pollachius virens L.) attracted to fish farms?
    John Wiley & Sons, 2020
    Co-Authors: Uglem Ingebrigt, Toledo-guedes Kilian, Sanchez-jerez Pablo, Ulvan, Eva M., Evensen Tor, Saether Bjørn-steinar
    Abstract:

    Salmon farms attract large amounts of wild fish, which prey on uneaten feed pellets. The modified diet of the wild fish aggregating at salmon farms may reduce the flesh quality of the fish, influencing the local fisheries. We compared the quality of saithe (Pollachius virens) captured near (farm associated—FA) or more than 5 km away (un‐associated—UA) from salmon farms in Norway. The fish were captured during summer, autumn and spring using two commercial fishing methods (jigging and bottom nets). Overall, the fillet quality of FA saithe was good, although it was clearly reduced for almost 10% of the catch. Moreover, the quality of the FA saithe was significantly reduced compared with UA saithe, but the differences were small. Our results also showed that fish caught with jigging had better quality than fish caught with nets, and that fish that died in the nets were of lower quality than fish that were alive after hauling. There was no clear variation among seasons in fillet quality. Although no major and overall differences in quality were found between FA and UA saithe, reduced quality for even a modest proportion of the fish may influence the value of the total catch.The study was funded by the Norwegian Seafood Research Fund through the ProCoEx project (Project number: 900772) and the Norwegian Research Council through the project ‘ECOCOAST’. Kilian Toledo‐Guedes was supported by a grant from Iceland, Liechtenstein and Norway through the EEA Financial Mechanism (ES07‐EEA Grants, 013‐ABEL‐IM‐2013), operated by Universidad Complutense de Madrid, and Juan de la Cierva Program FJCI‐2014‐20100 and IJCI‐2017‐34174 from Ministerio de Ciencia, Innovación y Universidades

  • Does a diet including pellets from salmon cage farms affect the taste of wild saithe (Pollachius virens Linnaeus, 1758)?
    'Wiley', 2017
    Co-Authors: Uglem Ingebrigt, Toledo-guedes Kilian, Ulvan, Eva M., Hegstad Erlend, Blakstad Steffen, Buserud Bjørnar, Saether Bjørn-steinar
    Abstract:

    The attraction of wild fish to net cage fish farms due to uneaten fish feed pellets that have fallen through the cages as waste feed, is a global phenomenon (Uglem, Karlsen, Sanchez-Jerez, & Sæther, 2014). The amount of feed not eaten by the farmed fish can reach up to 5% of the total amount in Norwegian salmon farming (Otterå, Karlsen, Slinde, & Olsen, 2009; Svåsand et al., 2015). This suggests that thousands of tonnes of waste feed are available to wild fish aggregating around these salmon farms. Farm-associated (FA) wild fish that have eaten a diet consisting partially of salmon feed are significantly fatter, with higher concentrations of terrestrial-derived fatty acids and lower concentrations of DHA in the muscle and liver than in unassociated (UA) fish (Dempster et al., 2011; Fernandez-Jover et al., 2011). Fish nutrition can influence the taste of the fish, either by variation in the biochemical composition of the tissues or by reducing the shelf life (Lie, 2001). Fishermen, fishmongers and consumers in Norway during the last couple of decades have reported that the taste of FA saithe (Pollachius virens) is inferior compared to UA fish (Uglem et al., 2014). The purpose of this study was to make taste comparisons of dishes made of either FA or UA saithe caught and processed using standardized means, by carrying out two simple consumer tests.This study was funded by the Norwegian Seafood Research Fund through the ProCoEx project (Project number: 900772) and the Norwegian Research Council through the project “ECOCOAST”. Kilian Toledo-Guedes was supported by a grant from Iceland, Liechtenstein and Norway through the EEA Financial Mechanism, operated by Universidad Complutense de Madrid

  • Commercial gillnetting is more stressful for saithe (Pollachius virens L.) than jigging: but is fillet quality affected?
    'EDP Sciences', 2016
    Co-Authors: Uglem Ingebrigt, Toledo-guedes Kilian, Ulvan, Eva Marita
    Abstract:

    Various fish capture methods, which involve different levels of pre-slaughter stress/welfare, could influence the final quality of marketed fish. In this study, living saithe (Pollachius virens L.), caught during realistic commercial fishing by gillnetting (n = 37) and automatic jigging (n = 50), were analysed for stress indicators in blood parameters. An assessment of the fillet quality of the same fish, after four days storage on ice, was carried out using an Industrial Test (IT) and a Quality Index Method (QIM). Stress indicators in gillnetted fish, such as lactate (7.5 ± 0.6 mmol/L), haematocrit (33.9 ± 1.2%) and glucose (6.7 ± 0.7 mmol/L) were significantly higher when compared to jigged fish (2.6 ± 0.2 mmol/L, 23.7 ± 0.7% and 3.3 ± 0.1 mmol/L, respectively), indicating higher stress levels for fish caught with gillnets. No differences due to fishing gear were detected in the quality indexes, which seemed to be influenced by a potential bias introduced when only fish hauled on board alive were analysed, and the limitations of the QIM and IT to detect small differences in quality. Condition factor (K) was positively correlated with IT for gillnetted fish, but not for jigged fish. This could also mask potential effects of capture methods on fillet quality. These results will be valuable given emerging concerns on fish welfare in commercial fisheries and the need to deliver fish products with high quality standards

  • A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations
    American Chemical Society, 2015
    Co-Authors: Marhuenda Egea, Frutos Carlos, Toledo-guedes Kilian, Sanchez-jerez Pablo, Ibanco-cañete Ricardo, Uglem Ingebrigt, Saether Bjørn-steinar
    Abstract:

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites.This research was funded by the Norwegian Seafood Research Fund through the project “Evaluation of actions to promote sustainable coexistence between salmon culture and coastal fisheries, ProCoEx” (Project 900772). K.T.-G. was supported by a grant from Iceland, Liechtenstein, and Norway through the EEA Financial Mechanism

  • Assessing the Influence of Salmon Farming through Total Lipids, Fatty Acids, and Trace Elements in the Liver and Muscle of Wild Saithe Pollachius virens
    Taylor & Francis, 2015
    Co-Authors: Arechavala-lopez Pablo, Marhuenda Egea, Frutos Carlos, Sanchez-jerez Pablo, Saether Bjørn-steinar, Uglem Ingebrigt
    Abstract:

    Saithe Pollachius virens are attracted to uneaten salmon feed underneath cages at open-cage salmon farms in Norway. The aggregated Saithe have modified their feeding habits as they have switched from wild prey to uneaten food pellets, which could lead to physiological and biochemical changes in the Saithe. Variations in profiles of total lipids, fatty acids, and trace elements in Saithe liver and muscle were measured to evaluate the influence of fish feed from salmon farms on wild Saithe populations. Farm-aggregated Saithe had higher fat content in liver tissues than did individuals captured more than 25 km away from farms, but no clear differences were found in muscle tissues. High proportions of fatty acids of terrestrial origin, such as oleic, linoleic, and linolenic acids, in liver and muscle tissues of farm-aggregated Saithe reflected the presence of wild Saithe at farms. Accordingly, low proportions of arachidonic, eicosapentaenoic, and docosahexaenoic acids in Saithe tissues mirrored the feeding activity at farms. Variations in specific trace element signatures among fish groups also revealed the farming influence on wild Saithe. High levels of Fe, As, Se, Zn, and B in liver, but also As, B, Li, Hg, and Sr in muscle of Saithe captured away from farms indicated the absence of feeding at farms.This study was part of the project “Evaluation of actions to promote sustainable coexistence between salmon culture and coastal fisheries – ProCoEx” funded by The Norwegian Seafood Research Fund (FHF). The study was also supported by the Norwegian Research Council through the EcoCoast project