This study was conducted to compare lipid and fatty acid composition of cod,haddock and halibut.Three groups of cod（276 g±61 g）,haddock（538 g±83 g）and halibut（3704 g±221 g）were maintained with com...This study was conducted to compare lipid and fatty acid composition of cod,haddock and halibut.Three groups of cod（276 g±61 g）,haddock（538 g±83 g）and halibut（3704 g±221 g）were maintained with commercial feeds mainly based on fish meal and marine fish oil for 12 weeks prior to sampling.The fatty acid compositions of muscle and liver were determined by GC/FID after derivatization of extracted lipids into fatty acid methyl esters（FAME）.Lipids were also fractionated into neutral and polar lipids using Waters silica Sep-Pak（R）.The phospholipid fraction was further separated by high-performance thin-layer chromatography（HPTLC）and the FAME profile was obtained.Results of the present study showed that cod and haddock were lean fish and their total muscle lipid contents were 0.8% and 0.7%,respectively,with phospholipid constituting 83.6% and 87.5% of the total muscle lipid,respectively.Halibut was a medium-fat fish and its muscle lipid content was 8%,with 84% of the total muscle lipid being neutral lipid.Total liver lipid contents of cod,haddock and halibut were 36.9%,67.2% and 30.7%,respectively,of which the neutral lipids accounted for the major fraction（88.1%-97.1%）.Polyunsaturated fatty acids were the most abundant in cod and haddock muscle neutral lipid.Monounsaturated fatty acid level was the highest in halibut muscle neutral lipid.Fatty acid compositions of phospholipid were relatively constant.In summary,the liver of cod and haddock as lean fish was the main lipid reserve organ,and structural phospholipid is the major lipid form in flesh.However,as a medium-fat fish,halibut stored lipid in both their liver and muscle.展开更多
To investigate the possible use of waste products obtained after processing haddock, the present study prepared haddock bone calcium powder by NaOH and ethanol soaking （alkalinealeohol method） and prepared haddock b...To investigate the possible use of waste products obtained after processing haddock, the present study prepared haddock bone calcium powder by NaOH and ethanol soaking （alkalinealeohol method） and prepared haddock bone calcium tablets using the powder in combination with appropriate excipients. The biological efficacy of the haddock bone calcium tablets was investigated using Wistar rats as an experiment model. Results show that the optimal parameters for the alkalinealcohol method are： NaOH concentration 1 mol/L, immersion time 30 h; ethanol concentration 60%, immersion time 15 h. A mixture of 2% polyvinylpyrrolidone in ethanol was used as an excipient at a ratio of 1：2 to full-cream milk powder, without the use of a disintegrating agent. This process provided satisfactory tablets in terms of rigidity and taste. Animal studies showed that the haddock bone calcium tablets at a dose of 2 g·kg^-1·d^-1 or 5g·kg^-1·d^-1 significantly increased blood calcium and phosphorus levels and bone calcium content in rats. Therefore, these tablets could be used for calcium supplementation and prevent osteoporosis. Although the reasons of high absorption in the rats fed with haddock bone calcium tablets are unclear, it is suggested that there are some factors, such as treatment with method of alkaline-alcohol or the added milk, may play positive roles in increasing absorption ratio.展开更多
Papain was used to hydrolyse fish frames under controlled conditions at a batch-pilot plant scale- process, for the production of fish protein hydrolysates (FPH). Mass balance calculations were carried out so that the...Papain was used to hydrolyse fish frames under controlled conditions at a batch-pilot plant scale- process, for the production of fish protein hydrolysates (FPH). Mass balance calculations were carried out so that the rate of hydrolysis, rate of protein solubilisation and yields could be estimated. Almost complete hydrolysis could be achieved in 1 hour, at 40oC, with no pH adjustment, at 0.5% (5 g.kg-1) enzyme to substrate ratio (E/S, were S is Kjeldahl protein) using whole fish frames (including heads and flaps). This was achieved both with the addition of water (1/1 to 2/1 frames/water) but more importantly from commercial considerations without the initial addition of water (after mincing of the fish material). The degree of protein solubilisation ranged between 71% - 86% w/w. Four different processes are described, namely: 1) a soluble spray-dried FPH powder 2) a liquid FPH 3) a partly soluble, spray dried FPH powder and 4) a crude, drum-dried protein for animal consumption. The amino acid profile of the FPH was identical to that of the parent substrate (fish frames).展开更多
Grid systems separate fish species primarily through physical means:fish size and body shape.On Georges Bank off the northeast USA,many species of flounders are overfished,and their catch needs to be reduced.Flat-bodi...Grid systems separate fish species primarily through physical means:fish size and body shape.On Georges Bank off the northeast USA,many species of flounders are overfished,and their catch needs to be reduced.Flat-bodied skates are also often discarded.We tested a European style horizontal-bar grid system to reduce these flat-bodied low quota species in a trawl targeting the haddock(Melanogrammus aeglefinus),whose population is robust.The grid system consisted of 4 grid sections,two on each side,with horizontal bars 70 mm apart.The alternating tow method was used to compare the catch characteristics between a trawl with a grid section and the same trawl without a grid section.A video camera was used to observe fish escape in the grid section.The results indicate that the grid system reduced the flounder catch rate(mainly winter flounder,Pseudopleuronectes americanus)by 51.3%,and skates(mainly winter skate,Leucoraja ocellata and little skate,Leucoraja erinacea)by 29.4%,while there were no differences in the catch of Atlantic cod(Gadus morhua).While haddock was reduced by 37%by weight,the reduction was primarily small undersized individuals.There was no reduction in large haddock greater than 50 cm.Video observations indicates that flounders and cod mainly escaped from the bottom half of the grid while haddock were from the top half.These finding suggest that this system reduced low quota flounders,as well as discarded skates and small haddock,while retaining Atlantic cod and large size haddock.Underwater observations indicate that differential spacing(narrower on the top and wider on the bottom)may improve the system performance by releasing more flat-bodied fish,that were observed to escape from the bottom part of the grid,while retaining more haddock,which typically escape from the top part of the grid.展开更多
文摘This study was conducted to compare lipid and fatty acid composition of cod,haddock and halibut.Three groups of cod（276 g±61 g）,haddock（538 g±83 g）and halibut（3704 g±221 g）were maintained with commercial feeds mainly based on fish meal and marine fish oil for 12 weeks prior to sampling.The fatty acid compositions of muscle and liver were determined by GC/FID after derivatization of extracted lipids into fatty acid methyl esters（FAME）.Lipids were also fractionated into neutral and polar lipids using Waters silica Sep-Pak（R）.The phospholipid fraction was further separated by high-performance thin-layer chromatography（HPTLC）and the FAME profile was obtained.Results of the present study showed that cod and haddock were lean fish and their total muscle lipid contents were 0.8% and 0.7%,respectively,with phospholipid constituting 83.6% and 87.5% of the total muscle lipid,respectively.Halibut was a medium-fat fish and its muscle lipid content was 8%,with 84% of the total muscle lipid being neutral lipid.Total liver lipid contents of cod,haddock and halibut were 36.9%,67.2% and 30.7%,respectively,of which the neutral lipids accounted for the major fraction（88.1%-97.1%）.Polyunsaturated fatty acids were the most abundant in cod and haddock muscle neutral lipid.Monounsaturated fatty acid level was the highest in halibut muscle neutral lipid.Fatty acid compositions of phospholipid were relatively constant.In summary,the liver of cod and haddock as lean fish was the main lipid reserve organ,and structural phospholipid is the major lipid form in flesh.However,as a medium-fat fish,halibut stored lipid in both their liver and muscle.
基金Supported by the Major Technology Project of Zhejiang Province (No. 2007C12013)
文摘To investigate the possible use of waste products obtained after processing haddock, the present study prepared haddock bone calcium powder by NaOH and ethanol soaking （alkalinealeohol method） and prepared haddock bone calcium tablets using the powder in combination with appropriate excipients. The biological efficacy of the haddock bone calcium tablets was investigated using Wistar rats as an experiment model. Results show that the optimal parameters for the alkalinealcohol method are： NaOH concentration 1 mol/L, immersion time 30 h; ethanol concentration 60%, immersion time 15 h. A mixture of 2% polyvinylpyrrolidone in ethanol was used as an excipient at a ratio of 1：2 to full-cream milk powder, without the use of a disintegrating agent. This process provided satisfactory tablets in terms of rigidity and taste. Animal studies showed that the haddock bone calcium tablets at a dose of 2 g·kg^-1·d^-1 or 5g·kg^-1·d^-1 significantly increased blood calcium and phosphorus levels and bone calcium content in rats. Therefore, these tablets could be used for calcium supplementation and prevent osteoporosis. Although the reasons of high absorption in the rats fed with haddock bone calcium tablets are unclear, it is suggested that there are some factors, such as treatment with method of alkaline-alcohol or the added milk, may play positive roles in increasing absorption ratio.
文摘Papain was used to hydrolyse fish frames under controlled conditions at a batch-pilot plant scale- process, for the production of fish protein hydrolysates (FPH). Mass balance calculations were carried out so that the rate of hydrolysis, rate of protein solubilisation and yields could be estimated. Almost complete hydrolysis could be achieved in 1 hour, at 40oC, with no pH adjustment, at 0.5% (5 g.kg-1) enzyme to substrate ratio (E/S, were S is Kjeldahl protein) using whole fish frames (including heads and flaps). This was achieved both with the addition of water (1/1 to 2/1 frames/water) but more importantly from commercial considerations without the initial addition of water (after mincing of the fish material). The degree of protein solubilisation ranged between 71% - 86% w/w. Four different processes are described, namely: 1) a soluble spray-dried FPH powder 2) a liquid FPH 3) a partly soluble, spray dried FPH powder and 4) a crude, drum-dried protein for animal consumption. The amino acid profile of the FPH was identical to that of the parent substrate (fish frames).
基金funded by NOAA Saltonstall-Kennedy Grant Program,Grant No.NA15NMF4270270.
文摘Grid systems separate fish species primarily through physical means:fish size and body shape.On Georges Bank off the northeast USA,many species of flounders are overfished,and their catch needs to be reduced.Flat-bodied skates are also often discarded.We tested a European style horizontal-bar grid system to reduce these flat-bodied low quota species in a trawl targeting the haddock(Melanogrammus aeglefinus),whose population is robust.The grid system consisted of 4 grid sections,two on each side,with horizontal bars 70 mm apart.The alternating tow method was used to compare the catch characteristics between a trawl with a grid section and the same trawl without a grid section.A video camera was used to observe fish escape in the grid section.The results indicate that the grid system reduced the flounder catch rate(mainly winter flounder,Pseudopleuronectes americanus)by 51.3%,and skates(mainly winter skate,Leucoraja ocellata and little skate,Leucoraja erinacea)by 29.4%,while there were no differences in the catch of Atlantic cod(Gadus morhua).While haddock was reduced by 37%by weight,the reduction was primarily small undersized individuals.There was no reduction in large haddock greater than 50 cm.Video observations indicates that flounders and cod mainly escaped from the bottom half of the grid while haddock were from the top half.These finding suggest that this system reduced low quota flounders,as well as discarded skates and small haddock,while retaining Atlantic cod and large size haddock.Underwater observations indicate that differential spacing(narrower on the top and wider on the bottom)may improve the system performance by releasing more flat-bodied fish,that were observed to escape from the bottom part of the grid,while retaining more haddock,which typically escape from the top part of the grid.
