6 research outputs found

    Fast-fase NMR-spektroskopi og MRI-studier av fettsyreprofiler direkte på fiskekjøtt. En sammenligning av oppdrettslaks og villaks

    Get PDF
    Postponed access: the file will be accessible after 2020-06-01The purpose of this project has been to determine the fat content, fat distribution and fatty acid composition in wild and farmed salmon using solid-state Nuclear Magnetic Resonance (NMR) spectroscopy and Magnetic Resonance Imaging (MRI). Rapid growth in the aquaculture industry over the past decades has, due to lack of enough marine resources, resulted in limited access to marine ingredients in the salmon feed. This has led to an increased use of alternative vegetable ingredients causing important long-chain marine ω-3-fatty acids like EPA and DHA to be replaced by shorter acyl chain fatty acids from vegetable oils like ALA. The composition of fatty acids in the salmon diet has shown to be reflected in the fatty acid composition of the filet, as well as affecting the fat profile in other parts of the fish. There is a lot of ongoing research on the use of alternative ingredients in the feed. For this purpose, effective and accurate analytical tools for control of salmon filet quality are required. The development of the feed composition causes a continuous change in quality and fatty acid composition in farmed salmon. Therefore, fast and direct techniques for analyzing salmon is of national and international interest. To quantify the fatty acids in salmon, it is important to have a precise analytical and quantitative method. In this project, solid-state 13^C NMR is used to verify a method that has recently been prepared to quantify the fatty acid composition in salmon. Further, solid-state 31^P NMR, both static and magic angle spinning, is used to investigate the phosphorous compounds in phospholipids in the salmon meat. MRI is used to investigate the fat distribution in the fillet and heart. Results showed that farmed salmon had a total fat content of 10%, twice the amount as in the wild salmon. Furthermore, the content of EPA and DHA is found to be 9.0% and 14.5% in the wild salmon, compared to 3.3% and 4.7% in farmed salmon, respectively. In addition, the farmed salmon contained 9,1% ALA. The phosphorus spectra showed differences in the phosphorous profiles of the salmons. The results from MRI showed differences in fat content and fat distribution in the fillets. In addition, MRI of the hearts of the salmons showed that the farmed salmon stored fat around the heart. The conclusion of this research is that there are significant differences in fat content, fat distribution and fat composition in farmed and wild salmon, and that solid-state NMR spectroscopy and MRI are reliable alternatives to current established methods.Formålet med dette arbeidet har vært å bestemme fettinnhold, fettfordeling og fettsammensetning i villaks og oppdrettslaks ved hjelp av fast-fase kjernemagnetisk resonans (NMR) spektroskopi og magnetisk resonans avbildning (MRI). Hurtig vekst i oppdrettsnæringen de siste tiårene har resultert i at tilgangen til de marine råvarene i fôret er blitt begrenset på grunn av knapphet av de marine råvarene. Dette har ført til økt bruk av alternative vegetabilske råvarer. Den økende andelen av vegetabilske ingredienser gjør at viktige langkjedete marine ω-3-fettsyrer som EPA og DHA er byttet ut med kortere-kjedede fettsyrer fra vegetabilske planteoljer som alfalinolensyre (ALA). Sammensetningen av fettsyrer i dietten til laksen har vist seg å gjenspeiles i fettsyresammensetningen i fileten, samt påvirke fettprofilen i andre deler av fisken. Det pågår mye forskning på bruk av alternative råvarer i fôret. For dette formålet er det nødvendig med effektive og presise analytiske verktøy for å kontrollere laksekvaliteten. Utviklingen av fôrsammensetningen forårsaker en kontinuerlig endring i kvaliteten og fettsyresammensetningen i oppdrettslaks. Derfor er hurtige og direkte teknikker for analyse av laks av stor nasjonal og internasjonal interesse. For å kvantifisere fettsyrene i laks er det viktig med en presis analytisk metode som er kvantitativ. I dette arbeidet brukes fast-fase 1^H NMR for å bestemme fettinnholdet i laks på en rask måte. Fast-fase 13^C NMR brukes for å verifisere en metode som nylig er utarbeid for å kvantifisere fettsyresammensetningen i laksen. Videre brukes fast-fase 31^P-NMR, både statisk og spinnende for å undersøke fosforforbindelser i fosfolipider i fiskekjøttet. MRI brukes for å undersøke fettfordeling i filet og hjerte. Resultatene viste at oppdrettslaksen hadde et totalt fettinnhold på 10%, noe som var dobbelt så høyt som i villaksen. Videre ble innholdet av EPA og DHA funnet til å være henholdsvis 9,0% og 14,5% i villaksen, sammenlignet med 3,3% og 4,7% i oppdrettslaksen. I tillegg inneholdt sistnevnte 9,1% ALA. Fosforspektrene viste ulikheter i fosforprofilene i laksene. Resultatene fra MRI viste forskjeller i fettinnhold og fordeling av fett i filetene. I tillegg viste MRI av hjertet til laksene at oppdrettslaksen lagret fett rundt hjertet. Konklusjonen i dette arbeidet er at det er forskjeller i fettinnhold, fettfordeling og fettsammensetning i oppdrettslaks og villaks, og at fast-fase NMR-spektroskopi og MRI er pålitelige alternativer til nåværende etablerte metoder.Masteroppgave i kjemiMAMN-KJEMKJEM39

    Fast-fase NMR-spektroskopi og MRI-studier av fettsyreprofiler direkte på fiskekjøtt. En sammenligning av oppdrettslaks og villaks

    No full text
    The purpose of this project has been to determine the fat content, fat distribution and fatty acid composition in wild and farmed salmon using solid-state Nuclear Magnetic Resonance (NMR) spectroscopy and Magnetic Resonance Imaging (MRI). Rapid growth in the aquaculture industry over the past decades has, due to lack of enough marine resources, resulted in limited access to marine ingredients in the salmon feed. This has led to an increased use of alternative vegetable ingredients causing important long-chain marine ω-3-fatty acids like EPA and DHA to be replaced by shorter acyl chain fatty acids from vegetable oils like ALA. The composition of fatty acids in the salmon diet has shown to be reflected in the fatty acid composition of the filet, as well as affecting the fat profile in other parts of the fish. There is a lot of ongoing research on the use of alternative ingredients in the feed. For this purpose, effective and accurate analytical tools for control of salmon filet quality are required. The development of the feed composition causes a continuous change in quality and fatty acid composition in farmed salmon. Therefore, fast and direct techniques for analyzing salmon is of national and international interest. To quantify the fatty acids in salmon, it is important to have a precise analytical and quantitative method. In this project, solid-state 13^C NMR is used to verify a method that has recently been prepared to quantify the fatty acid composition in salmon. Further, solid-state 31^P NMR, both static and magic angle spinning, is used to investigate the phosphorous compounds in phospholipids in the salmon meat. MRI is used to investigate the fat distribution in the fillet and heart. Results showed that farmed salmon had a total fat content of 10%, twice the amount as in the wild salmon. Furthermore, the content of EPA and DHA is found to be 9.0% and 14.5% in the wild salmon, compared to 3.3% and 4.7% in farmed salmon, respectively. In addition, the farmed salmon contained 9,1% ALA. The phosphorus spectra showed differences in the phosphorous profiles of the salmons. The results from MRI showed differences in fat content and fat distribution in the fillets. In addition, MRI of the hearts of the salmons showed that the farmed salmon stored fat around the heart. The conclusion of this research is that there are significant differences in fat content, fat distribution and fat composition in farmed and wild salmon, and that solid-state NMR spectroscopy and MRI are reliable alternatives to current established methods

    31P solid-state NMR on skeletal muscle of wild and farmed Atlantic salmon

    No full text
    Over the past 50 years, 31P NMR has proven a powerful tool for obtaining information on cellular biochemistry. Here we use this technique for the first time to study intracellular phosphorous metabolites in skeletal muscle tissue of wild and farmed salmon, to investigate possible effects due to differences in diet and way of life. The wild salmon sample shows a significantly more diverse composition of metabolites compared to the farmed salmon sample. The differences are evident in the entire spectrum, including regions displaying resonances from phosphomonoesters and sugar phosphates, as well as other molecules important for phospholipid metabolism. It is demonstrated that 31P MAS NMR can be used to study a broad range of phosphorus metabolites ex vivo, which can give useful information, both on its own or as a supplement to other extraction-based analyses. Further 31P MAS NMR investigations on farmed salmon raised under different controlled conditions may give important insights into the broad array of health issues seen in farmed salmon

    31P solid-state NMR on skeletal muscle of wild and farmed Atlantic salmon

    Get PDF
    Over the past 50 years, 31P NMR has proven a powerful tool for obtaining information on cellular biochemistry. Here we use this technique for the first time to study intracellular phosphorous metabolites in skeletal muscle tissue of wild and farmed salmon, to investigate possible effects due to differences in diet and way of life. The wild salmon sample shows a significantly more diverse composition of metabolites compared to the farmed salmon sample. The differences are evident in the entire spectrum, including regions displaying resonances from phosphomonoesters and sugar phosphates, as well as other molecules important for phospholipid metabolism. It is demonstrated that 31P MAS NMR can be used to study a broad range of phosphorus metabolites ex vivo, which can give useful information, both on its own or as a supplement to other extraction-based analyses. Further 31P MAS NMR investigations on farmed salmon raised under different controlled conditions may give important insights into the broad array of health issues seen in farmed salmon
    corecore