Differences in muscle cellularity and flesh quality between wild and farmed Coilia nasus (Engraulidae)

BACKGROUND: Populations of Coilia nasus, an anadromous fish, have declined dramatically in the Yangtze River estuary and its associated lakes owing to excessive fishing and changes in aquatic ecology. Recently, the success of artificial breeding programmes and advanced methods of propagation have allowed great increases in production of this species. Thus, to gain a better understanding of the flesh quality of C. nasus, muscle cellularity and quality parameters of the flesh were studied in wild and farmed specimens. RESULTS: Muscle cellularity was different between wild and farmed fish. Muscle fibre density was significantly higher in farmed specimens, while muscle fibre diameter was higher in wild specimens. Farmed fish had higher moisture, hydroxyproline and collagen contents and a lower fat content compared with wild fish. No significant differences in textural parameters were found between the two groups. Saturated (SFA), polyunsaturated (PUFA) and total n‐6 fatty acid contents were significantly higher in farmed fish, but monounsaturated fatty acid (MUPA) content was higher in wild fish. CONCLUSION: The variation in the studied parameters determined significant differences in the flesh quality of wild and farmed C. nasus. Depending on muscle cellularity and fatty acid composition, farmed fish could be more suitable for human consumption than wild fish. Copyright © 2011 Society of Chemical Industry     

Effects of differences in diet and seasonal changes on the fatty acid composition in fillets from farmed and wild sea bream (Sparus aurata L.) and sea bass (Dicentrarchus labrax L.)

The effects of dietary fatty acids and seasonal variation on the fatty acid profiles of farmed and wild sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) were determined by analysis of their fillets. Farmed sea bream and sea bass were fed on the same commercial feeds all year. Fatty acid profiles in the fillets reflected the fatty acid profiles of the commercial feeds. The predominant fatty acids in the trial feeds, fillets of farmed and wild sea bream and sea bass were 16:0, 18:1n‐9, 18:2n‐6, 20:5n‐3 and 22:6n‐3. The fatty acid profiles in the fillets of farmed sea bream and sea bass did not differ (P > 0.05) except in the winter season compared with those of their wild counterparts. However, the content of eicosapentaenoic acid (20:5n‐3), docosahexaenoic acid (22:6n‐3) in the fillets of the farmed and wild sea bass were significantly (P < 0.05) higher than the farmed and wild sea bream. The wild sea bream had significantly (P < 0.05) higher total saturated fatty acid and monounsaturated fatty acid (MUFA) levels, and lower total n‐6 and n‐3 polyunsaturated fatty acid (PUFA) levels in winter than in the summer and spring seasons. Similarly, in the fillets of wild sea bass, total n‐3 PUFA levels were significantly (P < 0.05) lower, and the MUFA levels were higher in winter than in the other seasons. These results indicate that the farmed fish fillets were good sources of n‐3 PUFA in each of the three seasons. However, wild fish were good sources of n‐3 PUFA in the spring and summer.     

Composition of total,neutral and phospholipids in wild and farmed tambaqui (Colossoma macropomum) in the Brazilian Amazon area

BACKGROUND: Fishing is a traditional extractive activity in the Amazonian region, representing an important factor in the economy of the area. The wet and dry cycles cause extreme changes in the chemical composition of the water. This study aimed to investigate the fatty acid composition of the total lipid (TL), neutral lipid (NL) and phospholipid (PL) fractions of the dorsal muscle, orbital cavity and abdominal cavity fat of farmed and wild tambaqui in the Amazon area captured in different seasons. RESULTS: Fatty acids were analyzed by high‐resolution gas chromatography/mass spectrometry. Sixty‐one fatty6 acids were detected in the TL, 67 in the NL and 58 in the PL. The main fatty acids found in the TL, NL and PL of farmed and wild fish were oleic, palmitic, stearic and linoleic acids. Higher levels of eicosapentaenoic and docosahexaenoic acids were observed in PL compared with NL. No distinctions in the quantity of these fractions between dorsal muscle and orbital cavity were found. CONCLUSION: The season had a significant influence on TL and fatty acid composition. Fish caught in the wild are considered superior for consumption. The seasonal characteristics of the Amazon influenced the composition of fatty acid composition in the species. Fish captured during the dry season showed a higher percentage of long‐chain polyunsaturated fatty acids. Copyright © 2008 Society of Chemical Industry     

Comparative assessment of proximate composition,physicochemical parameters,fatty acid profile and mineral content in farmed and wild rainbow trout (Oncorhynchus mykiss)

This study was conducted to determine differences between farmed and wild rainbow trout in terms of proximate and fatty acid composition, physicochemical parameters and mineral content. Fat content of farmed fish fillets was higher, while moisture content was lower than wild fish. However, wild fish had higher pH value and water‐holding capacity comparing to farmed fish. The muscle lipids of farmed fish contained higher proportions of 20:0, 18:1n‐9 and 20:1n‐9; and lower proportions of 18:2n‐6, 20:2cis, 18:3n‐3, 20:3n‐6, 20:4n‐6, 20:5n‐3 and 22:6n‐3 fatty acids than wild fish. The percentage of total saturated fatty acids (SFAs) was similar in both fish. Total polyunsaturated fatty acids (PUFAs), n‐3 PUFAs and n‐3/n‐6 PUFAs ratio were higher in the wild fish comparing to farmed fish, whereas its total monounsaturated fatty acids (MUFAs) and n‐6 PUFAs contents were lower. Among the seventeen minerals analysed in fish flesh, differences existed between farmed and wild rainbow trout in Ca and Fe contents. Moreover, toxic trace minerals (As, Cd, Pb and Hg) were all present in amounts below their toxic levels. The differences observed between farmed and wild fish may be attributed to the diet constituents and environmental conditions of the fish.     

Fatty acid composition of total lipids,neutral lipids and phospholipids in wild and farmed matrinxã (Brycon cephalus) in the Brazilian Amazon area

BACKGROUND: The chemical composition of Amazonian fish is extremely variable, being influenced by the season and the type and amount of food. A special interest in the fish oil composition has been developed owing to the presence of essential fatty acids, since this is directly related to human health. This study aimed to investigate the fatty acid composition (FAC) of the total lipid (TL), neutral lipid (NL) and phospholipid (PL) fractions of the dorsal muscle and orbital cavity of farmed and wild matrinxã in the Amazon area captured in different seasons. RESULTS: Fatty acids (FA) were analysed by high‐resolution gas chromatography/mass spectrometry. Sixty‐five FA were detected in the TL, 66 in the NL and 55 in the PL. The main FA found in farmed and wild fish were oleic, palmitic, stearic and linoleic acids. No distinctions in the quality or quantity of these fractions between dorsal muscle and orbital cavity were found. CONCLUSION: The season had a significant influence on the TL and FAC. Fish captured during the dry season showed lower levels of lipid and a higher percentage of long‐chain polyunsaturated fatty acids. Matrinxã farmed in a semi‐intensive system showed a nutritional quality comparable to that of wild matrinxã captured in the wet season. Copyright © 2007 Society of Chemical Industry     

Comparative study of proximate composition and amino acid in farmed and wild Pseudobagrus ussuriensis muscles

The proximate composition and amino acid compositions of the muscle of wild and farmed Pseudobagrus ussuriensis were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish. Pseudobagrus ussuriensis protein has a well‐balanced amino acid composition. The percentages of total amino acids, essential amino acids, nonessential amino acids and delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of W_EAA to W_TAA (42.78%–43.02%) and W_EAA to W_NEAA (85.52%–87.74%) were comparable to the reference values of 40% and above 60% recommended by FAO/WHO. According to the amino acid scores, methionine would have been described as the first limiting amino acid, and Lys had the highest score for the protein in both wild and farmed Pseudobagrus ussuriensis. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources.     

养殖和野生长吻鮠肌肉营养成分比较分析

采用常规生化分析方法对养殖和野生长吻鮠肌肉营养成分进行分析,并对其营养品质进行评价。结果表明,养殖长吻鮠水分极显著高于野生长吻鮠（P＜0.01）,蛋白质、脂肪极显著低于野生长吻鮠（P＜0.01）;养殖长吻鮠氨基酸总量（干基）显著高于野生长吻鮠（P＜0.05）,必需氨基酸无显著差异（P＞0.05）,氨基酸组成均完全符合联合国粮食及农业组织/世界卫生组织标准,鲜味氨基酸总量极显著高于野生长吻鮠（P＜0.01）;单不饱和脂肪酸总量极显著低于野生长吻鮠（P＜0.01）,n-6多不饱和脂肪酸总量极显著高于野生长吻鮠（P＜0.01）,n-3多不饱和脂肪酸总量无显著差异（P＞0.05）,致动脉粥样硬化指数、血栓形成指数无显著差异（P＞0.05）。研究表明,与野生长吻鮠相比,养殖长吻鮠营养品质没有降低,通过调整饲料配方,可进一步提高养殖长吻鮠的营养品质。     

Differentiation in the Lipid Quality of Wild and Farmed Seabass (Dicentrarchus labrax) and Gilthead Sea Bream (Sparus aurata)

ABSTRACT: The elements of differentiation that characterize the quality of the lipid fraction of wild and farmed sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) were investigated. Reared fish of either species had a total lipid content significantly higher than the wild counterparts. Liquid chromatography of unsaponifiable lipids showed, on a lipid gram basis, higher cholesterol levels in wild fish and comparable amounts of squalene, all‐trans retinol, and α‐tocopherol. Gas chromatography of total lipids revealed differences between the fatty acid profiles of wild and reared fish.     

野生与养殖鳡鱼肌肉的营养成分比较

对野生鳡鱼和养殖鳡鱼的营养品质进行研究。结果表明：这两种鱼肌肉中水分含量差异不显著(P＝0.07779＞0.05),而粗蛋白、粗灰分含量野生鳡鱼显著高于养殖鳡鱼(P＝0.00115、0.00415＜0.05),养殖鳡鱼粗脂肪含量显著高于野生鳡鱼(P＝0.000215＜0.05)。养殖鳡鱼的必需氨基酸指数为94.16,而野生鳡鱼则为66.03,其构成比例符合联合国粮农组织/世界卫生组织(FAO/WHO)的标准。野生和养殖鳡鱼肌肉脂肪酸中二十碳五烯酸(EPA)+二十二碳六烯酸(DHA)含量分别为4.25%和4.8%。综合所得结果,养殖鳡鱼氨基酸组成及结构、EPA+DHA含量均优于野生鳡鱼,但野生鳡鱼蛋白质含量与n-3/n-6多不饱和脂肪酸(PUFA)比例优于养殖鳡鱼。     

Seasonal variations on total fatty acid composition of fillets of zander (Sander lucioperca) in Beysehir Lake (Turkey)

Seasonal variations on total fatty acid compositions of zander, Sander lucioperca in Beysehir Lake, were determined by using GC. Polyunsaturated fatty acids (PUFA) were found to be higher than saturated (SFA) and monounsaturated fatty acids (MUFA) in all seasons. Palmitic acid was the major SFA (57.0–64.0% of total SFA) in all seasons. Oleic acid was identified as the major MUFA (45.0–58.0% of total MUFAs). Docosahexaenoic acid (DHA), linoleic acid (LA), eicosapentaenoic acid (EPA), and arachidonic acid (AA) were the most abundant PUFA. Relating to the total fatty acid composition of zander, the percentages of DHA, LA, AA, and EPA ranged between 17.1–23.3%, 5.40–15.4%, 6.72–9.94% and 4.22–5.93% of total lipid, respectively. The percentages of total ω3 fatty acid were higher than those of total ω6 fatty acid in the fatty acid composition of zander with ω3/ω6 ratios of 1.49, 1.45, 1.22, 0.72 in spring, autumn, winter, and summer, respectively. It was shown that the fatty acid composition and ω3/ω6 fatty acids ratio in the muscle of zander were significantly influenced by spawning and season.     

Lipid Changes of Freeze-Dried Spinach by Various Kinds of Oxidation

: Lipid changes in freeze‐dried spinach by various oxidations were studied by using thin‐layer chromatography and gas chromatography. There were no characteristic changes in lipids by the oxidation except decrease in esterified sterols in NL and phosphatidic acid and phosphatidylcholine in PL. Stability of the freeze‐dried spinach lipid to the oxidation was higher when it was in the form of total lipid than when separated into NL, GL, or PL. Autoxidation and enzyme‐catalyzed oxidation resulted in the highest fatty‐acid composition change in NL. However, photooxidation showed the biggest change in PL and GL. C₁₆ fatty acids tended to be more stable than C₁₈ fatty acids to the oxidation.     

Fatty acid profile of wild and farmed gilthead sea bream (Sparus aurata)

Historically farmed fish were frequently found to exhibit a lower ratio of n3/n6 fatty acids compared to wild fish. This study compares the proximate and fatty acid composition of wild and cultured gilthead sea bream fish from a lagoon in NW Greece. Wild fish contained less fat and showed different fatty acid profiles. Farmed fish exhibited threefold higher concentrations of linoleic acid (C18:2n-6) in muscle and twofold in visceral fat. Their muscle tissue contained higher levels of saturated fatty acids and higher ratios of eicosapentaenoic acid/docosahexaenoic acid (0.49 ± 0.04 vs. 0.03 ± 0.01; Ρ < 0.001). Wild fish exhibited lower levels of muscle n-3 fatty acids (15.87 ± 0.82 vs. 19.89 ± 1.06; P < 0.001) but a higher ratio of n-3/n-6 (2.22 ± 0.14 vs. 1.64 ± 0.10, Ρ < 0.001). These results emphasize the need to further explore dietary manipulation of fatty acid content as a method of improving the fatty acid profile and maximise the health benefits of consuming farmed fish.     

Differentiation of Cultured and Wild Sturgeon (Acipenser oxyrinchus desotoi) Based on Fatty Acid Composition

Sturgeon species have attracted interest for aquaculture due to high value of the flesh, caviar and wild stock depletion. Lipid was extracted from sturgeon muscle using the Bligh and Dyer procedure. Fatty acids from total lipid were methylated using boron-trifluoride in methanol. Fatty acid methyl esters were analyzed by gas chromatography as weight %. The fatty acid profiles of lipids were different between cultured and wild sturgeon. Wild sturgeon had higher levels of 16:0, 16:1ω7, 18:1ω9, 22: 4ω6 and 22:5ω6. Cultured fish had higher levels of 18:2ω6, C20 and C22 monoenes, 20:5ω3 and 22:6ω3. Stepwise discriminant analysis (SDA) was used to develop a mathematical model to distinguish the two populations; the levels of 16:2ω6, 22:5ω6 and phytanic acid accurately identified the two fish populations.     

Lipid composition of the intramuscular fat of beef from Spanish cattle breeds stored under modified atmosphere

The lipid composition of intramuscular fat from 30 young bulls of 5 Spanish cattle breeds (Asturiana de los Valles, Morucha, Parda Alpina, Pirenaica and Retinta) was studied. Steaks from each shortloin were packaged in 60% O(2), 30% CO(2) and 10% N(2) and aged for 0, 5, 10 and 15 days. Lipid classes obtained by thin layer chromatography and total fatty acids obtained by gas chromatography were evaluated. Meat from Asturiana de los Valles had high PL and C contents, and low TG contents that reflected its low intramuscular percentage content. This breed showed high FFA content that likely originated from lipolysis of PL. The main breed effect was due to the low intramuscular fat content observed in the Asturiana de los Valles. After 5 days, FFA decreased because they were probably transformed into other compounds. The Morucha breed may have a genetic predisposition for depositing MUFA, and the high MUFA and C14:0 values observed in the Morucha breed were likely due to its high intramuscular fat percentage. Regarding fatty acid composition, no "days of storage" effect was observed for any of the studied fatty acids, except for C18:3ω6 that increased during the first 5 days of storage in Asturiana de los Valles. Concerning the fatty acid composition, Asturiana de los Valles had the highest PUFA/SFA ratio, while Parda Alpina and Morucha possessed low ω6/ω3 ratios but high C22:6ω3 contents. Finally, the presence of C22:6ω3 and 15-CH(3)-C16:0 may be related to higher intramuscular fat contents.     

Identification of organically farmed Atlantic salmon by analysis of stable isotopes and fatty acids

Using isotope ratio mass spectrometry (IRMS), the ratios of carbon (δ ¹³C) and nitrogen (δ ¹⁵N) stable isotopes were investigated in raw fillets of differently grown Atlantic salmon (Salmo salar) in order to develop a method for the identification of organically farmed salmon. IRMS allowed to distinguish organically farmed salmon (OS) from wild salmon (WS), with δ ¹⁵N-values being higher in OS, but not from conventionally farmed salmon (CS). The gas chromatographic analysis of fatty acids differentiated WS from CS by stearic acid as well as WS from CS and OS by either linoleic acid or α-linolenic acid, but not OS from CS. The combined data were subjected to analysis using an artificial neural network (ANN). The ANN yielded several combinations of input data that allowed to assign all 100 samples from Ireland and Norway correctly to the three different classes. Although the complete assignment could already be achieved using fatty acid data only, it appeared to be more robust with a combination of fatty acid and IRMS data, i.e. with two independent analytical methods. This is also favourable with respect to a possible manipulation using suitable feed components. A good differentiation was established even without an ANN by the δ ¹⁵N-value and the content of linoleic acid. The general applicability in the context of consumer protection should be checked with further samples, particularly regarding the variability of feed composition and possible changes in smoked salmon.     

Fatty acid profile of wild and farmed gilthead sea bream (Sparus aurata)

Historically farmed fish were frequently found to exhibit a lower ratio of n3/n6 fatty acids compared to wild fish. This study compares the proximate and fatty acid composition of wild and cultured gilthead sea bream fish from a lagoon in NW Greece. Wild fish contained less fat and showed different fatty acid profiles. Farmed fish exhibited threefold higher concentrations of linoleic acid (C18:2n-6) in muscle and twofold in visceral fat. Their muscle tissue contained higher levels of saturated fatty acids and higher ratios of eicosapentaenoic acid/docosahexaenoic acid (0.49?±?0.04 vs. 0.03?±?0.01; ???<?0.001). Wild fish exhibited lower levels of muscle n-3 fatty acids (15.87?±?0.82 vs. 19.89?±?1.06; P?<?0.001) but a higher ratio of n-3/n-6 (2.22?±?0.14 vs. 1.64?±?0.10, ???<?0.001). These results emphasize the need to further explore dietary manipulation of fatty acid content as a method of improving the fatty acid profile and maximise the health benefits of consuming farmed fish.     

Comparison of wild and cultured sea bass (Dicentrarchus labrax) quality

Chemical composition, nutritional value and other physico-chemical parameters of sea bass from two different geographical areas (Greece and Spain) and from aquaculture and wild origin were studied. Farmed and wild fish differ in proximate composition, colour, and especially in texture, fatty acids and free amino acids (FAAs) profiles. Flesh of wild fish was firmer, which could be attributed to their lower fat content and higher level of activity. Cultured fish showed a higher content of monounsaturated fatty acids and lower of saturated and polyunsaturated fatty acids (PUFAs). Within the PUFA group, n−3 fatty acids were predominant in wild sea bass, while n−6 were more abundant in farmed fish. Some FAAs related to the characteristic flavour of fish, such as glutamic acid, aspartic acid, alanine, and glycine were more abundant in cultured sea bass. No differences between fish from both farms were found, due to the similar composition of the feed used.     

Fatty acids distribution in different tissues of wild and reared Seriola dumerili

In this study, we compared the lipid and fatty acids content, between cultured and wild Seriola dumerili, in different edible portions. Results showed that cultured fish contained a higher level of lipids than wild fish. The fatty acids profiles revealed that, among all the split‐fish side, palmitic (C16:0) and oleic (C18:1n‐9) acid were the principal saturated and monounsaturated fatty acids, in cultured and wild S. dumerili. On the other hand, wild S. dumerili contained a higher level of saturated (38.12 ± 0.54% vs. 33.66 ± 0.15% in cultured fish), monounsaturated (33.13 ± 1.07% vs. 26.49 ± 0.17%), n‐3 polyunsaturated fatty acids (PUFA) (23.90 ± 1.02% vs. 19.77 ± 0.51%) particularly docosahexaenoic acid (DHA) (18.83 ± 0.48% vs. 11.77 ± 0.42%). However, the cultured fish showed a higher level of n‐6 PUFA due principally to the higher value of linoleic acid (C18:2n‐6). In fact, changes in fatty acids content between anatomical areas marked differences in the muscle quality of wild and cultured S. dumerili. According to this study, both groups of wild and farmed S. dumerili have nutritional benefits for human health. Cultured fish were characterised by higher hypocholesterolaemic and hypercholesterolaemic fatty acids ratio for all samples studied and a lower n‐3/n‐6 ratio due to the abundance of n‐3 PUFA particularly DHA in wild fish.     

Change in proximate, amino acid and fatty acid contents in muscle tissue of rainbow trout (Oncorhynchus mykiss) after cooking

Changes in proximate, amino acid and fatty acid composition of farmed, commercially important rainbow trout (Oncorhynchus mykiss) after conventional and microwave cooking were analysed. Rainbow trouts cooked in microwave ovens had statistically significant higher total protein, total fat, and ash than electrical oven‐cooked samples. The amounts of essential and nonessential amino acids were not different between cooking methods, but the difference between raw and cooked samples was significant. Lysine, leusine, methionine, threonine, valine, arginine and histidine were found most in microwave‐cooked rainbow trouts whereas isoleucine, tyrosine and phenylalanine were found most in electrical oven‐cooked samples. As total saturated fatty acid and total monounsaturated fatty acids amount were not statistically different between the cooking methods, the difference between raw and cooked fillets was found statistically significant (P < 0.05). There was no statistically significant difference between raw and cooked fillets in total n‐3 and n‐6 contents.