The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) ... more The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). These omega-3 fatty acids are highly susceptible to oxidation. Peptides exhibiting antioxidative capacity (AOC) are encrypted in seafood muscle proteins. Such components may protect the fatty acids during digestion and uptake, as well as exhibit antioxidative effects in general. The oxygen radical absorbance capacity (ORAC) assay and the ferric reducing antioxidant power (FRAP) assay were used to study the changes in AOC of fish and shrimp muscle and their aqueous fractions, referred to as press juice (PJ), during a simulated in vitro gastrointestinal (GI) digestion. Blueberry (Vaccinium myrtillus), well-known for its AOC, was included for comparison. During digestion the AOC increased in all samples. After digestion the AOC of muscle of both autumn saithe and shrimp were higher (130-165 micromol/g), and winter saithe comparable (110 micromol/g) to digested blueberry when measured by ORAC. The AOC of PJ was low in general (5-20 micromol/g). When measured by FRAP, blueberry exhibited ten times the AOC of seafood muscle. Antioxidative compounds in seafood increased significantly during digestion, and may offer protection of other beneficial food components such as EPA and DHA.
ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable ... more ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable oils in the feed for farmed fish, such as Atlantic salmon. The aim of this study was to evaluate how this has affected the fatty acid (FA) composition of farmed Atlantic salmon and to compare the FA composition of 20 farmed Atlantic salmon with that of 20 wild Atlantic salmon caught in the sea. Fillet fat of farmed salmon was about 12%, which is twice that found in wild salmon. The FA composition of the farmed salmon confirmed a substantial inclusion of vegetable oils in the feed, but the total amount of long chain n-3 FA present in the fillets of farmed salmon was higher than in the wild fish. A standard portion of farmed Atlantic salmon fillet (200 g) provides approximately 2 g of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which is four times higher than the minimum daily intakes recommended by the UK’s Scientific Advisory Committee on Nutrition and the World Health Organisation.
ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 p... more ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 polyunsaturated fatty acids (n-3 PUFAs). Other nutrients, such as taurine (a component that is abundant in seafood) have been found to contribute to beneficial effects. In this chapter, the dietary need for taurine is discussed, the taurine content of marine and other foods is presented, and the link between taurine, seafood, and health-promoting effects is outlined.
The aim of this study was to investigate the effect of dietary supplementation with an oil extrac... more The aim of this study was to investigate the effect of dietary supplementation with an oil extracted from the zooplankton copepod Calanus finmarchicus [calanus oil (CO)] on atherosclerosis in apoE-deficient (apoE(-/-)) mice. Thirty 6-wk-old female apoE(-/-) mice (n = 10/group) were fed: 1) a Western-type, high-fat diet (HFD); 2) HFD supplemented with 1% (wt:wt) CO; or 3) HFD supplemented with 0.88% (wt:wt) corn oil + 0.12% (wt:wt) EPA+DHA ethyl esters (EPA+DHA) for 13 wk. Dietary CO supplementation lowered total aorta atherogenesis by 36.5% compared to the HFD (P < 0.01), whereas the reduction in the lesion prone aortic arch was 34.8% (P < 0.01). The degree of aortic atherogenesis was intermediate in mice fed EPA+DHA compared to those fed HFD and CO. The effect on atherogenesis was paralleled by reduced expression of hepatic genes for the proinflammatory cytokines, Ccl2, Icam1, Il1b, and Nfkb1, in mice fed CO compared to those fed HFD. For mice fed EPA+DHA, gene expression did not differ compared to those fed CO or HFD. Plasma concentrations of total cholesterol, TG, and cytokines did not differ between the groups at the end of the study. However, mice fed CO gained more weight compared to those fed HFD but not compared to those fed EPA+DHA. In conclusion, dietary CO supplementation attenuated atherosclerotic lesion formation in female apoE(-/-) mice and may be an effective and safe dietary intervention to reduce the development of atherosclerosis. However, further studies are warranted to elucidate the underlying physiological and molecular mechanisms.
ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. ... more ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. In recent years, increased attention has been directed towards the potential health benefits of peptides of marine origin. Some peptides have been found to exhibit antioxidative and antihypertensive properties. This chapter reviews the properties of marine-derived peptides and evaluates their health benefits. Whereas antioxidative peptides may provide a beneficial effect in the gut, preventing unwanted food oxidation, angiotensin-converting enzyme (ACE) inhibitory peptides need to be absorbed in the intestine in order to enter the bloodstream and exert a physiological effect at the target site. According to theoretical knowledge, the antioxidants can prevent oxidative stress linked to several diseases, such as cardiovascular diseases (CVD), diabetes, neurodegenerative disorders and cancer, as well as ageing. Evaluation of the antihypertensive effects of ACE inhibitors from marine sources covers in vitro studies, animal studies and human clinical trials.
ABSTRACT Bioaccessibility of plant proteins has been shown to be inferior to that of proteins of ... more ABSTRACT Bioaccessibility of plant proteins has been shown to be inferior to that of proteins of animal origin. Heat treatment has been shown to positively affect this in some plants. The aim of this study was to investigate the effect of heat treatment on bioaccessibility of seaweed proteins. An in vitro gastrointestinal digestion model was used for evaluation of potential effects on the brown seaweed Alaria esculenta and the red seaweed Palmaria palmata proteins. In P. palmata, the content of accessible amino acids increased by 86-109 % after heat treatment. Following a simulated in vitro gastrointestinal digestion, the amount of liberated amino acids was 64-96 % higher in heat-treated samples compared to their raw counterparts. The increase was largest in samples boiled for 15 and 30 min. No deterioration of single amino acids was seen, and hence, the amount of available essential amino acids was increased accordingly. In A. esculenta, no equivalent changes were observed. In conclusion, a short heat treatment may be a simple way of increasing the utilization potential of seaweed proteins in food and feed. However, there are species differences, and the effects observed in the in vitro digestion model need to be confirmed in clinical studies.
ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. ... more ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. In recent years, increased attention has been directed towards the potential health benefits of peptides of marine origin. Some peptides have been found to exhibit antioxidative and antihypertensive properties. This chapter reviews the properties of marine-derived peptides and evaluates their health benefits. Whereas antioxidative peptides may provide a beneficial effect in the gut, preventing unwanted food oxidation, angiotensin-converting enzyme (ACE) inhibitory peptides need to be absorbed in the intestine in order to enter the bloodstream and exert a physiological effect at the target site. According to theoretical knowledge, the antioxidants can prevent oxidative stress linked to several diseases, such as cardiovascular diseases (CVD), diabetes, neurodegenerative disorders and cancer, as well as ageing. Evaluation of the antihypertensive effects of ACE inhibitors from marine sources covers in vitro studies, animal studies and human clinical trials.
ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable ... more ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable oils in the feed for farmed fish, such as Atlantic salmon. The aim of this study was to evaluate how this has affected the fatty acid (FA) composition of farmed Atlantic salmon and to compare the FA composition of 20 farmed Atlantic salmon with that of 20 wild Atlantic salmon caught in the sea. Fillet fat of farmed salmon was about 12%, which is twice that found in wild salmon. The FA composition of the farmed salmon confirmed a substantial inclusion of vegetable oils in the feed, but the total amount of long chain n-3 FA present in the fillets of farmed salmon was higher than in the wild fish. A standard portion of farmed Atlantic salmon fillet (200 g) provides approximately 2 g of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which is four times higher than the minimum daily intakes recommended by the UK’s Scientific Advisory Committee on Nutrition and the World Health Organisation.
International Journal of Food Sciences and Nutrition, 2009
Processing of foods can lead to losses of water-soluble components, and some of these may have be... more Processing of foods can lead to losses of water-soluble components, and some of these may have beneficial health effects. Taurine has lately attracted attention due to its suggested strong contribution to the health-promoting effects of seafood. The lack of systematic information on the content of conditionally essential nutrients, such as taurine, has led to this study. The taurine concentrations in a variety of common marine dinners and spreads, and their corresponding raw materials, have been determined. Losses of taurine in processed products ranged up to 100% when compared with the taurine content of freshly caught specimens. Products soaked in brines or products subjected to rough processing conditions such as mincing and washing had greater loss compared with products with more intact muscle. Levels of taurine in processed seafood vary according to product type and brand, showing a potential for the industry to take measures in preventing losses of taurine and other water-soluble components.
Norwegian reindeer of Finnmark county live under harsh conditions on extensive feed sources. Thus... more Norwegian reindeer of Finnmark county live under harsh conditions on extensive feed sources. Thus the meat may have special qualities. M. longissimus lumborum from 30 animals was investigated with respect to carcass and meat quality and compositional/nutritional characteristics. Meat from calves had a higher myofibrillar fragmentation index and tenderness, and had lighter, redder and more yellow colour than meat from adult reindeer. Regarding nutritional compounds the meat from calves had lower antioxidant capacity, and higher taurine levels than adults, while the levels of iron, carnosine, anserine, and vitamin E were similar. Carcass weights of the adult reindeer were lower than the weights reported for Swedish reindeer and New Zealand farmed red deer. Reindeer muscles had higher antioxidant capacity, shorter sarcomeres, smaller muscle fibre diameters, higher n-6/n-3 ratios of fatty acids in the intramuscular fat and higher muscle taurine levels relative to values for the same muscle of New Zealand farmed red deer.
ABSTRACT The objective of this study was to examine the biochemical composition of intensively re... more ABSTRACT The objective of this study was to examine the biochemical composition of intensively reared rotifers after enrichment with three commonly used enrichment media, Multigain, Ori-Green and DHA-enriched freshwater algae Chlorella, using standard enrichment protocols at a local cod larvae producer and compare it with that of natural zooplankton from Lofilab AS, a cod larvae producer using semi-intensive rearing techniques. Unenriched rotifers were analysed to examine whether the enrichment procedures were successful in increasing the content of essential nutrients to level requirements for marine fish larvae. Neither total lipids nor proteins were affected by enrichment. Unenriched rotifers were significantly lower in highly unsaturated fatty acids (HUFAs) and significantly higher in linoleic acid (LA, C18:2, n-6), than were zooplankton. Enrichment with Chlorella and Multigain increased the HUFAs significantly, while they were slightly reduced after enrichment with Ori-Green. Total amino acids and mineral content were unaffected by enrichment. Zooplankton was rich in taurine and selenium, whereas rotifers were devoid of it, both prior to and after enrichment. Using zooplankton as a reference for the nutritional requirements of marine fish larvae, results from this study demonstrate that enrichment media currently in use are not effective for enhancing the nutritional quality of rotifers.
Industrial processing and heat treatment of fish muscle generally lead to losses of water-soluble... more Industrial processing and heat treatment of fish muscle generally lead to losses of water-soluble components, some of which may have beneficial health effects. The aim of this work was to determine the retention of taurine, selenium and n-3 polyunsaturated fatty acids when preparing African catfish by three traditional household techniques: boiling in pouches, deep-frying and baking. Cooking did not significantly reduce the content of selenium, having retention between 91and 104%. Deepfrying resulted in a taurine loss of 40%, which was significantly higher than in baking where losses were 25% The fatty acid profiles were similar for baked and boiled fillets, but were significantly different from deep-fried fillets, due to absorption of vegetable frying oil. Baking was the best preparation technique with regard to retention of 20:5n-3 (eicosapentaenoic acid; EPA) and 22:6n-3 (docosahexaenoic acid, DHA), retaining above 80% for both fatty acids, whereas boiling and deep-frying were able to retain only approximately 54 and 65% of each, respectively.
ω-3 fatty acids (n-3 FA) have, since the 1970s, been associated with beneficial health effects. T... more ω-3 fatty acids (n-3 FA) have, since the 1970s, been associated with beneficial health effects. They are, however, prone to lipid peroxidation due to their many double bonds. Lipid peroxidation is a process that may lead to increased oxidative stress, a condition associated with adverse health effects. Recently, conflicting evidence regarding the health benefits of intake of n-3 from seafood or n-3 supplements has emerged. The aim of this review was thus to examine recent literature regarding health aspects of n-3 FA intake from fish or n-3 supplements, and to discuss possible reasons for the conflicting findings. There is a broad consensus that fish and seafood are the optimal sources of n-3 FA and consumption of approximately 2-3 servings per week is recommended. The scientific evidence of benefits from n-3 supplementation has diminished over time, probably due to a general increase in seafood consumption and better pharmacological intervention and acute treatment of patients with cardiovascular diseases (CVD).
Journal of the Science of Food and Agriculture, 2014
The objectives of this study were to examine protein and amino acid composition, lipid and fatty ... more The objectives of this study were to examine protein and amino acid composition, lipid and fatty acid composition, along with a range of essential minerals in common Norwegian seaweed species representing the red (Palmaria palmata and Vertebrata lanosa), green (Cladophora rupestris, Enteromorpha intestinalis and Ulva lactuca) and brown (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Fucus vesiculosus and Pelvetia canaliculata) classes and assess their potential as alternatives to cereals in food and feed. As macroalgae accumulate heavy metals, arsenic, cadmium and mercury were also analyzed. Proteins ranged from 34 to 123 g kg(-1) dry weight (DW) and the essential amino acid levels may cover both human and salmonid requirements. Lipids were low (6-58 g kg(-1) DW), but the red algae had high relative content of long-chained omega-3 fatty acids (32-34 % of the fatty acids). Iodine contents were particularly high in the Laminaria species. Of the heavy metals only arsenic levels may be of concern. In total, the red alga P. palmata was regarded as the best alternative to cereals in food and feed. For several of the other species, single-component extraction for the ingredients market may be better than using the whole product.
ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 p... more ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 polyunsaturated fatty acids (n-3 PUFAs). Other nutrients, such as taurine (a component that is abundant in seafood) have been found to contribute to beneficial effects. In this chapter, the dietary need for taurine is discussed, the taurine content of marine and other foods is presented, and the link between taurine, seafood, and health-promoting effects is outlined.
The aim of this study was to investigate the effect of dietary supplementation with an oil extrac... more The aim of this study was to investigate the effect of dietary supplementation with an oil extracted from the zooplankton copepod Calanus finmarchicus [calanus oil (CO)] on atherosclerosis in apoE-deficient (apoE 2/2 ) mice. Thirty 6-wk-old female apoE 2/2 mice (n = 10/group) were fed: 1) a Western-type, high-fat diet (HFD); 2) HFD supplemented with 1% (wt:wt) CO; or 3) HFD supplemented with 0.88% (wt:wt) corn oil + 0.12% (wt:wt) EPA+DHA ethyl esters (EPA+DHA) for 13 wk. Dietary CO supplementation lowered total aorta atherogenesis by 36.5% compared to the HFD (P , 0.01), whereas the reduction in the lesion prone aortic arch was 34.8% (P , 0.01). The degree of aortic atherogenesis was intermediate in mice fed EPA+DHA compared to those fed HFD and CO. The effect on atherogenesis was paralleled by reduced expression of hepatic genes for the proinflammatory cytokines, Ccl2, Icam1, Il1b, and Nfkb1, in mice fed CO compared to those fed HFD. For mice fed EPA+DHA, gene expression did not differ compared to those fed CO or HFD. Plasma concentrations of total cholesterol, TG, and cytokines did not differ between the groups at the end of the study. However, mice fed CO gained more weight compared to those fed HFD but not compared to those fed EPA+DHA. In conclusion, dietary CO supplementation attenuated atherosclerotic lesion formation in female apoE 2/2 mice and may be an effective and safe dietary intervention to reduce the development of atherosclerosis.
The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) ... more The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). These omega-3 fatty acids are highly susceptible to oxidation. Peptides exhibiting antioxidative capacity (AOC) are encrypted in seafood muscle proteins. Such components may protect the fatty acids during digestion and uptake, as well as exhibit antioxidative effects in general. The oxygen radical absorbance capacity (ORAC) assay and the ferric reducing antioxidant power (FRAP) assay were used to study the changes in AOC of fish and shrimp muscle and their aqueous fractions, referred to as press juice (PJ), during a simulated in vitro gastrointestinal (GI) digestion. Blueberry (Vaccinium myrtillus), well-known for its AOC, was included for comparison. During digestion the AOC increased in all samples. After digestion the AOC of muscle of both autumn saithe and shrimp were higher (130-165 μmol/g), and winter saithe comparable (110 μmol/g) to digested blueberry when measured by ORAC. The AOC of PJ was low in general (5-20 μmol/g). When measured by FRAP, blueberry exhibited ten times the AOC of seafood muscle. Antioxidative compounds in seafood increased significantly during digestion, and may offer protection of other beneficial food components such as EPA and DHA.
Changes in content of selenium and taurine, and the alteration of fatty acid profile have been st... more Changes in content of selenium and taurine, and the alteration of fatty acid profile have been studied in African catfish fillets subjected to a commercial cold- or hot smoking process. Selenium content and the fatty acid profile did not change significantly during neither of the smoking procedures. Losses of taurine were 32 and 19 % during cold-smoking and hot-smoking, respectively. Significantly more taurine was lost during cold-smoking (P < 0.05), probably due to the prolonged brining and smoking procedure. The results support conclusions from other studies, showing that low molecular water soluble components are more susceptible to losses during processing of seafood.
The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) ... more The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). These omega-3 fatty acids are highly susceptible to oxidation. Peptides exhibiting antioxidative capacity (AOC) are encrypted in seafood muscle proteins. Such components may protect the fatty acids during digestion and uptake, as well as exhibit antioxidative effects in general. The oxygen radical absorbance capacity (ORAC) assay and the ferric reducing antioxidant power (FRAP) assay were used to study the changes in AOC of fish and shrimp muscle and their aqueous fractions, referred to as press juice (PJ), during a simulated in vitro gastrointestinal (GI) digestion. Blueberry (Vaccinium myrtillus), well-known for its AOC, was included for comparison. During digestion the AOC increased in all samples. After digestion the AOC of muscle of both autumn saithe and shrimp were higher (130-165 micromol/g), and winter saithe comparable (110 micromol/g) to digested blueberry when measured by ORAC. The AOC of PJ was low in general (5-20 micromol/g). When measured by FRAP, blueberry exhibited ten times the AOC of seafood muscle. Antioxidative compounds in seafood increased significantly during digestion, and may offer protection of other beneficial food components such as EPA and DHA.
ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable ... more ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable oils in the feed for farmed fish, such as Atlantic salmon. The aim of this study was to evaluate how this has affected the fatty acid (FA) composition of farmed Atlantic salmon and to compare the FA composition of 20 farmed Atlantic salmon with that of 20 wild Atlantic salmon caught in the sea. Fillet fat of farmed salmon was about 12%, which is twice that found in wild salmon. The FA composition of the farmed salmon confirmed a substantial inclusion of vegetable oils in the feed, but the total amount of long chain n-3 FA present in the fillets of farmed salmon was higher than in the wild fish. A standard portion of farmed Atlantic salmon fillet (200 g) provides approximately 2 g of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which is four times higher than the minimum daily intakes recommended by the UK’s Scientific Advisory Committee on Nutrition and the World Health Organisation.
ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 p... more ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 polyunsaturated fatty acids (n-3 PUFAs). Other nutrients, such as taurine (a component that is abundant in seafood) have been found to contribute to beneficial effects. In this chapter, the dietary need for taurine is discussed, the taurine content of marine and other foods is presented, and the link between taurine, seafood, and health-promoting effects is outlined.
The aim of this study was to investigate the effect of dietary supplementation with an oil extrac... more The aim of this study was to investigate the effect of dietary supplementation with an oil extracted from the zooplankton copepod Calanus finmarchicus [calanus oil (CO)] on atherosclerosis in apoE-deficient (apoE(-/-)) mice. Thirty 6-wk-old female apoE(-/-) mice (n = 10/group) were fed: 1) a Western-type, high-fat diet (HFD); 2) HFD supplemented with 1% (wt:wt) CO; or 3) HFD supplemented with 0.88% (wt:wt) corn oil + 0.12% (wt:wt) EPA+DHA ethyl esters (EPA+DHA) for 13 wk. Dietary CO supplementation lowered total aorta atherogenesis by 36.5% compared to the HFD (P &amp;amp;amp;amp;amp;amp;lt; 0.01), whereas the reduction in the lesion prone aortic arch was 34.8% (P &amp;amp;amp;amp;amp;amp;lt; 0.01). The degree of aortic atherogenesis was intermediate in mice fed EPA+DHA compared to those fed HFD and CO. The effect on atherogenesis was paralleled by reduced expression of hepatic genes for the proinflammatory cytokines, Ccl2, Icam1, Il1b, and Nfkb1, in mice fed CO compared to those fed HFD. For mice fed EPA+DHA, gene expression did not differ compared to those fed CO or HFD. Plasma concentrations of total cholesterol, TG, and cytokines did not differ between the groups at the end of the study. However, mice fed CO gained more weight compared to those fed HFD but not compared to those fed EPA+DHA. In conclusion, dietary CO supplementation attenuated atherosclerotic lesion formation in female apoE(-/-) mice and may be an effective and safe dietary intervention to reduce the development of atherosclerosis. However, further studies are warranted to elucidate the underlying physiological and molecular mechanisms.
ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. ... more ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. In recent years, increased attention has been directed towards the potential health benefits of peptides of marine origin. Some peptides have been found to exhibit antioxidative and antihypertensive properties. This chapter reviews the properties of marine-derived peptides and evaluates their health benefits. Whereas antioxidative peptides may provide a beneficial effect in the gut, preventing unwanted food oxidation, angiotensin-converting enzyme (ACE) inhibitory peptides need to be absorbed in the intestine in order to enter the bloodstream and exert a physiological effect at the target site. According to theoretical knowledge, the antioxidants can prevent oxidative stress linked to several diseases, such as cardiovascular diseases (CVD), diabetes, neurodegenerative disorders and cancer, as well as ageing. Evaluation of the antihypertensive effects of ACE inhibitors from marine sources covers in vitro studies, animal studies and human clinical trials.
ABSTRACT Bioaccessibility of plant proteins has been shown to be inferior to that of proteins of ... more ABSTRACT Bioaccessibility of plant proteins has been shown to be inferior to that of proteins of animal origin. Heat treatment has been shown to positively affect this in some plants. The aim of this study was to investigate the effect of heat treatment on bioaccessibility of seaweed proteins. An in vitro gastrointestinal digestion model was used for evaluation of potential effects on the brown seaweed Alaria esculenta and the red seaweed Palmaria palmata proteins. In P. palmata, the content of accessible amino acids increased by 86-109 % after heat treatment. Following a simulated in vitro gastrointestinal digestion, the amount of liberated amino acids was 64-96 % higher in heat-treated samples compared to their raw counterparts. The increase was largest in samples boiled for 15 and 30 min. No deterioration of single amino acids was seen, and hence, the amount of available essential amino acids was increased accordingly. In A. esculenta, no equivalent changes were observed. In conclusion, a short heat treatment may be a simple way of increasing the utilization potential of seaweed proteins in food and feed. However, there are species differences, and the effects observed in the in vitro digestion model need to be confirmed in clinical studies.
ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. ... more ABSTRACT The health benefits of a diet rich in seafood (fish and shellfish) are well recognised. In recent years, increased attention has been directed towards the potential health benefits of peptides of marine origin. Some peptides have been found to exhibit antioxidative and antihypertensive properties. This chapter reviews the properties of marine-derived peptides and evaluates their health benefits. Whereas antioxidative peptides may provide a beneficial effect in the gut, preventing unwanted food oxidation, angiotensin-converting enzyme (ACE) inhibitory peptides need to be absorbed in the intestine in order to enter the bloodstream and exert a physiological effect at the target site. According to theoretical knowledge, the antioxidants can prevent oxidative stress linked to several diseases, such as cardiovascular diseases (CVD), diabetes, neurodegenerative disorders and cancer, as well as ageing. Evaluation of the antihypertensive effects of ACE inhibitors from marine sources covers in vitro studies, animal studies and human clinical trials.
ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable ... more ABSTRACT The limited amount of fish oils available has resulted in an increased use of vegetable oils in the feed for farmed fish, such as Atlantic salmon. The aim of this study was to evaluate how this has affected the fatty acid (FA) composition of farmed Atlantic salmon and to compare the FA composition of 20 farmed Atlantic salmon with that of 20 wild Atlantic salmon caught in the sea. Fillet fat of farmed salmon was about 12%, which is twice that found in wild salmon. The FA composition of the farmed salmon confirmed a substantial inclusion of vegetable oils in the feed, but the total amount of long chain n-3 FA present in the fillets of farmed salmon was higher than in the wild fish. A standard portion of farmed Atlantic salmon fillet (200 g) provides approximately 2 g of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which is four times higher than the minimum daily intakes recommended by the UK’s Scientific Advisory Committee on Nutrition and the World Health Organisation.
International Journal of Food Sciences and Nutrition, 2009
Processing of foods can lead to losses of water-soluble components, and some of these may have be... more Processing of foods can lead to losses of water-soluble components, and some of these may have beneficial health effects. Taurine has lately attracted attention due to its suggested strong contribution to the health-promoting effects of seafood. The lack of systematic information on the content of conditionally essential nutrients, such as taurine, has led to this study. The taurine concentrations in a variety of common marine dinners and spreads, and their corresponding raw materials, have been determined. Losses of taurine in processed products ranged up to 100% when compared with the taurine content of freshly caught specimens. Products soaked in brines or products subjected to rough processing conditions such as mincing and washing had greater loss compared with products with more intact muscle. Levels of taurine in processed seafood vary according to product type and brand, showing a potential for the industry to take measures in preventing losses of taurine and other water-soluble components.
Norwegian reindeer of Finnmark county live under harsh conditions on extensive feed sources. Thus... more Norwegian reindeer of Finnmark county live under harsh conditions on extensive feed sources. Thus the meat may have special qualities. M. longissimus lumborum from 30 animals was investigated with respect to carcass and meat quality and compositional/nutritional characteristics. Meat from calves had a higher myofibrillar fragmentation index and tenderness, and had lighter, redder and more yellow colour than meat from adult reindeer. Regarding nutritional compounds the meat from calves had lower antioxidant capacity, and higher taurine levels than adults, while the levels of iron, carnosine, anserine, and vitamin E were similar. Carcass weights of the adult reindeer were lower than the weights reported for Swedish reindeer and New Zealand farmed red deer. Reindeer muscles had higher antioxidant capacity, shorter sarcomeres, smaller muscle fibre diameters, higher n-6/n-3 ratios of fatty acids in the intramuscular fat and higher muscle taurine levels relative to values for the same muscle of New Zealand farmed red deer.
ABSTRACT The objective of this study was to examine the biochemical composition of intensively re... more ABSTRACT The objective of this study was to examine the biochemical composition of intensively reared rotifers after enrichment with three commonly used enrichment media, Multigain, Ori-Green and DHA-enriched freshwater algae Chlorella, using standard enrichment protocols at a local cod larvae producer and compare it with that of natural zooplankton from Lofilab AS, a cod larvae producer using semi-intensive rearing techniques. Unenriched rotifers were analysed to examine whether the enrichment procedures were successful in increasing the content of essential nutrients to level requirements for marine fish larvae. Neither total lipids nor proteins were affected by enrichment. Unenriched rotifers were significantly lower in highly unsaturated fatty acids (HUFAs) and significantly higher in linoleic acid (LA, C18:2, n-6), than were zooplankton. Enrichment with Chlorella and Multigain increased the HUFAs significantly, while they were slightly reduced after enrichment with Ori-Green. Total amino acids and mineral content were unaffected by enrichment. Zooplankton was rich in taurine and selenium, whereas rotifers were devoid of it, both prior to and after enrichment. Using zooplankton as a reference for the nutritional requirements of marine fish larvae, results from this study demonstrate that enrichment media currently in use are not effective for enhancing the nutritional quality of rotifers.
Industrial processing and heat treatment of fish muscle generally lead to losses of water-soluble... more Industrial processing and heat treatment of fish muscle generally lead to losses of water-soluble components, some of which may have beneficial health effects. The aim of this work was to determine the retention of taurine, selenium and n-3 polyunsaturated fatty acids when preparing African catfish by three traditional household techniques: boiling in pouches, deep-frying and baking. Cooking did not significantly reduce the content of selenium, having retention between 91and 104%. Deepfrying resulted in a taurine loss of 40%, which was significantly higher than in baking where losses were 25% The fatty acid profiles were similar for baked and boiled fillets, but were significantly different from deep-fried fillets, due to absorption of vegetable frying oil. Baking was the best preparation technique with regard to retention of 20:5n-3 (eicosapentaenoic acid; EPA) and 22:6n-3 (docosahexaenoic acid, DHA), retaining above 80% for both fatty acids, whereas boiling and deep-frying were able to retain only approximately 54 and 65% of each, respectively.
ω-3 fatty acids (n-3 FA) have, since the 1970s, been associated with beneficial health effects. T... more ω-3 fatty acids (n-3 FA) have, since the 1970s, been associated with beneficial health effects. They are, however, prone to lipid peroxidation due to their many double bonds. Lipid peroxidation is a process that may lead to increased oxidative stress, a condition associated with adverse health effects. Recently, conflicting evidence regarding the health benefits of intake of n-3 from seafood or n-3 supplements has emerged. The aim of this review was thus to examine recent literature regarding health aspects of n-3 FA intake from fish or n-3 supplements, and to discuss possible reasons for the conflicting findings. There is a broad consensus that fish and seafood are the optimal sources of n-3 FA and consumption of approximately 2-3 servings per week is recommended. The scientific evidence of benefits from n-3 supplementation has diminished over time, probably due to a general increase in seafood consumption and better pharmacological intervention and acute treatment of patients with cardiovascular diseases (CVD).
Journal of the Science of Food and Agriculture, 2014
The objectives of this study were to examine protein and amino acid composition, lipid and fatty ... more The objectives of this study were to examine protein and amino acid composition, lipid and fatty acid composition, along with a range of essential minerals in common Norwegian seaweed species representing the red (Palmaria palmata and Vertebrata lanosa), green (Cladophora rupestris, Enteromorpha intestinalis and Ulva lactuca) and brown (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Fucus vesiculosus and Pelvetia canaliculata) classes and assess their potential as alternatives to cereals in food and feed. As macroalgae accumulate heavy metals, arsenic, cadmium and mercury were also analyzed. Proteins ranged from 34 to 123 g kg(-1) dry weight (DW) and the essential amino acid levels may cover both human and salmonid requirements. Lipids were low (6-58 g kg(-1) DW), but the red algae had high relative content of long-chained omega-3 fatty acids (32-34 % of the fatty acids). Iodine contents were particularly high in the Laminaria species. Of the heavy metals only arsenic levels may be of concern. In total, the red alga P. palmata was regarded as the best alternative to cereals in food and feed. For several of the other species, single-component extraction for the ingredients market may be better than using the whole product.
ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 p... more ABSTRACT The health benefits of a diet high in seafood cannot be fully explained by the omega-3 polyunsaturated fatty acids (n-3 PUFAs). Other nutrients, such as taurine (a component that is abundant in seafood) have been found to contribute to beneficial effects. In this chapter, the dietary need for taurine is discussed, the taurine content of marine and other foods is presented, and the link between taurine, seafood, and health-promoting effects is outlined.
The aim of this study was to investigate the effect of dietary supplementation with an oil extrac... more The aim of this study was to investigate the effect of dietary supplementation with an oil extracted from the zooplankton copepod Calanus finmarchicus [calanus oil (CO)] on atherosclerosis in apoE-deficient (apoE 2/2 ) mice. Thirty 6-wk-old female apoE 2/2 mice (n = 10/group) were fed: 1) a Western-type, high-fat diet (HFD); 2) HFD supplemented with 1% (wt:wt) CO; or 3) HFD supplemented with 0.88% (wt:wt) corn oil + 0.12% (wt:wt) EPA+DHA ethyl esters (EPA+DHA) for 13 wk. Dietary CO supplementation lowered total aorta atherogenesis by 36.5% compared to the HFD (P , 0.01), whereas the reduction in the lesion prone aortic arch was 34.8% (P , 0.01). The degree of aortic atherogenesis was intermediate in mice fed EPA+DHA compared to those fed HFD and CO. The effect on atherogenesis was paralleled by reduced expression of hepatic genes for the proinflammatory cytokines, Ccl2, Icam1, Il1b, and Nfkb1, in mice fed CO compared to those fed HFD. For mice fed EPA+DHA, gene expression did not differ compared to those fed CO or HFD. Plasma concentrations of total cholesterol, TG, and cytokines did not differ between the groups at the end of the study. However, mice fed CO gained more weight compared to those fed HFD but not compared to those fed EPA+DHA. In conclusion, dietary CO supplementation attenuated atherosclerotic lesion formation in female apoE 2/2 mice and may be an effective and safe dietary intervention to reduce the development of atherosclerosis.
The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) ... more The health effects of seafood have primarily been linked to eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). These omega-3 fatty acids are highly susceptible to oxidation. Peptides exhibiting antioxidative capacity (AOC) are encrypted in seafood muscle proteins. Such components may protect the fatty acids during digestion and uptake, as well as exhibit antioxidative effects in general. The oxygen radical absorbance capacity (ORAC) assay and the ferric reducing antioxidant power (FRAP) assay were used to study the changes in AOC of fish and shrimp muscle and their aqueous fractions, referred to as press juice (PJ), during a simulated in vitro gastrointestinal (GI) digestion. Blueberry (Vaccinium myrtillus), well-known for its AOC, was included for comparison. During digestion the AOC increased in all samples. After digestion the AOC of muscle of both autumn saithe and shrimp were higher (130-165 μmol/g), and winter saithe comparable (110 μmol/g) to digested blueberry when measured by ORAC. The AOC of PJ was low in general (5-20 μmol/g). When measured by FRAP, blueberry exhibited ten times the AOC of seafood muscle. Antioxidative compounds in seafood increased significantly during digestion, and may offer protection of other beneficial food components such as EPA and DHA.
Changes in content of selenium and taurine, and the alteration of fatty acid profile have been st... more Changes in content of selenium and taurine, and the alteration of fatty acid profile have been studied in African catfish fillets subjected to a commercial cold- or hot smoking process. Selenium content and the fatty acid profile did not change significantly during neither of the smoking procedures. Losses of taurine were 32 and 19 % during cold-smoking and hot-smoking, respectively. Significantly more taurine was lost during cold-smoking (P < 0.05), probably due to the prolonged brining and smoking procedure. The results support conclusions from other studies, showing that low molecular water soluble components are more susceptible to losses during processing of seafood.
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