广西养殖黄沙鳖营养品质研究

为了构建广西黄沙鳖食用品质和营养价值评价方法,对不同重量梯度的3种鳖肌肉、裙边组织的营养成分进行对比分析。结果显示,在相同重量下,养殖黄沙鳖肌肉粗蛋白含量均高于中华鳖和野生鳖;野生鳖肌肉粗脂肪含量最低;养殖黄沙鳖裙边胶原蛋白含量最高。3种鳖的裙边胶原蛋白分子量不大,属I型胶原蛋白。养殖黄沙鳖大腿肌肉含维生素种类最多,肝脏次之,裙边最少。广西的养殖黄沙鳖营养丰富,具有较高食用价值。     

野生和养殖乌鳢肌肉的成分分析及营养评价

本文对野生和养殖乌鳢肌肉中的营养成分进行了分析和营养评价。结果表明:野生乌鳢肌肉中粗脂肪含量显著低于养殖乌鳢(P0.05)。野生乌鳢n-3多不饱和脂肪酸含量和c22:6(DHA)含量均高于养殖乌鳢,野生和养殖乌鳢肌肉中n-3/n-6的比例分别为1.21和0.65。两种乌鳢肌肉都检测到了17种氨基酸,养殖乌鳢肌肉中氨基酸总量、鲜味氨基酸含量、必需氨基酸含量均高于野生乌鳢,野生和养殖乌鳢肌肉中必需氨基酸/总氨基酸(EAA/TAA)的比值分别为42.66%和42.28%,必需氨基酸/非必需氨基酸(EAA/NEAA)的比值分别为74.40%和73.26%,均高于FAO/WHO推荐的理想蛋白质模式,野生和养殖乌鳢肌肉的必需氨基酸评分(EAAI)分别为63.48和70.82。两种乌鳢肌肉中矿物质元素均以钾最高,养殖乌鳢微量元素含量显著高于野生乌鳢(P0.05)。因此,以低值野杂鱼饵料为食物来源的养殖乌鳢具有良好的开发前景。     

气相色谱法测定不同水域刀鲚肉中脂肪酸含量

对刀鲚肉中脂肪酸含量气相色谱分析的甲酯化方法:硫酸-甲醇法、氢氧化钾-甲醇法和三氟化硼-甲醇法进行了选择,采用内标法对长江刀鲚、东海刀鲚和黄河刀鲚肉中脂肪酸进行了定量分析。方法的精密度良好,RSD值3%,回收率在93%~108%之间(n=3)。三种刀鲚肉中检测到29种脂肪酸,共有脂肪酸27种,其中东海刀鲚肉中未能检测到C10∶0和C24∶0。三种刀鲚肉的多不饱和脂肪酸(PUFA)与饱和脂肪酸(SFA)的比值P∶S值均高于0.4,长江刀鲚、东海刀鲚和黄河刀鲚肉的AI值分别为0.47、0.38、0.40。单不饱和脂肪酸含量高,占脂肪酸总量的50%以上,其中C16∶1和C18∶1n9c两种分别对风味和营养有重要作用的脂肪酸含量丰富。三种刀鲚脂肪酸含量存在显著差异(p0.05)。东海刀鲚中DHA含量显著(p0.05)高于长江刀鲚和黄河刀鲚。从脂肪酸含量及组成来看,东海刀鲚的营养价值高于其他两种刀鲚,而从C16∶1和C18∶0的含量上来看,长江刀鲚的风味则更胜一筹。     

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。     

长江刀鲚、黄河刀鲚与东海刀鲚熟制肉的滋味成分差异

采用火焰原子吸收光谱、高效液相色谱和氨基酸自动分析等方法分析比较长江刀鲚、黄河刀鲚与东海刀鲚蒸制肉的滋味物质成分,计算各呈味物质的滋味强度值,结果表明K+、PO43-和呈味核苷酸5’-IMP的含量对刀鲚的滋味贡献显著,游离氨基酸起到辅助呈味的作用。随着刀鲚由东海向长江和黄河的洄游,除洄游至长江的刀鲚K+含量显著上升外,洄游刀鲚的其他几种离子含量均显著下降,而5’-核苷酸含量显著上升(p0.05)。通过计算味精当量发现鲜味对刀鲚整体的滋味贡献显著,长江刀鲚与黄河刀鲚的味精当量值均显著高于东海刀鲚,这可能是洄游型刀鲚味道更为鲜美的原因之一。     

4种来源大黄鱼营养成分的比较分析

目的 比较4个不同产地大黄鱼(福建宁德养殖、浙江温州养殖、浙江舟山养殖和舟山自然海域野生)的营养组成。方法 采用国标分析方法对4个产地大黄鱼背部肌肉中的一般营养成分(水分、灰分、粗蛋白和粗脂肪)、矿物元素、氨基酸和脂肪酸含量进行定量和差异比较分析。结果 4种产地大黄鱼肌肉中,水分、灰分和粗蛋白质含量无显著性差别(P＞0.05),野生大黄鱼脂肪含量明显最低(P＜0.05),福建宁德养殖大黄鱼脂肪含量显著性最高(P＜0.05)。舟山野生大黄鱼中Mg、K,Se,Asp,Glu,Lys,∑EAA,∑TAA,∑FAA和∑BAA均含量均显著高于其它3种产地(P<0.05),Zn含量最高且明显高于福建宁德与浙江温州两产地(P<0.05),而Cu含量明显低于温州和舟山养殖大黄鱼(P<0.05)。除温州养殖大黄鱼略低外,其它3个产地大黄鱼的∑EAA/∑TAA和∑EAA/∑NEAA分别在40.73%~41.13%和68.72%~69.80%,符合优质蛋白源条件。C16:0、C18:1n9c、C22:6n3和C20:5n3是大黄鱼肌肉中最为丰富的脂肪酸,福建宁德养殖大黄鱼中FA、SFA和UFA含量均显著高于其它3种产地,舟山野生大黄鱼中ΣPUFA/ΣUFA占比高达78.6%,特别是EPA和DHA的总含量明显高于养殖大黄鱼。结论 不同产地环境及养殖方式会导致大黄鱼的营养成分有所差异。野生大黄鱼在低脂肪、有益矿物元素、鲜味氨基酸和多不饱和脂肪酸含量上较养殖大黄鱼有明显优势,但养殖鱼类可以显著提高蛋白质及脂肪酸含量,均具有较高的食用与营养保健价值。     

产卵前后长江刀鲚肉中营养成分差异

对比研究了产卵前后长江刀鲚肉的营养价值以及在产卵过程中营养成分的代谢。结果表明产卵后长江刀鲚肉粗脂肪含量显著降低(p0.05)。两个时期的鱼肉均含有丰富的脂肪酸,尤其是单不饱和脂肪酸。产卵后大部分不饱和脂肪酸含量显著下降,而饱和脂肪酸所占比例显著上升。不饱和脂肪酸中C17∶1,C20∶4和C18∶2n6c含量下降最多,分别为97.72%,96.67%和88.77%。而C14∶1与C20∶3n6的含量发生显著性上升。产卵前后刀鲚肉中n-3/n-6为7.71、9.32,P/S为0.40、0.60。产卵后氨基酸总量显著高于产卵前(p0.05),分别为60.00 g/100 g和43.17 g/100 g(干重)。其中半必需氨基酸His含量升高最多,增长了85.12%。产卵前后刀鲚肉AAS值均大于100,EAAI值为157、161。产卵前后K的积累和Na的消减与刀鲚产卵时向淡水洄游的生殖洄游习性相吻合,产卵后Cu和Mn含量显著降低,用于产卵过程中维持卵巢发育。两个时期的刀鲚肉中均含有丰富的Ca。     

不同养殖模式罗非鱼品质的比较

比较分析鱼菜共生养殖、纯投料养殖2 种养殖模式奥尼罗非鱼的肌肉营养成分、感官特性、理化特性、氨 基酸组成及含量。结果显示：2 种养殖模式下罗非鱼的水分、粗脂肪、粗灰分和总糖含量之间无显著差异,而粗蛋 白的含量差异显著;感官评定中,2 种养殖模式下的罗非鱼的鲜味存在显著差异,而口感、嫩度及可接受值差异均 不显著;理化指标中,2 种养殖模式的罗非鱼最终pH值、熟肉率和蒸煮损失均无显著差异,持水性、滴水损失、肌 内脂肪、肌原纤维断裂指数、肌红蛋白含量有显著差异;肌肉中检测到18 种常见氨基酸,天冬氨酸、脯氨酸、精氨 酸的含量差异显著（P＜0.05）,其他氨基酸含量无显著差异（P＞0.05）;2 种养殖模式的罗非鱼必需氨基酸总量分 别为22.49%（鱼菜共生模式）和22.45%（纯投料模式）,无显著差异;鱼菜共生模式养殖的罗非鱼中鲜味氨基酸总 量显著高于纯投料模式;甜味氨基酸总量分别为45.13%（鱼菜共生模式）和51.18%（纯投料模式）,无显著差异。     

池塘养殖与野生三疣梭子蟹滋味的比较研究

池塘养殖和野生捕捞是食用三疣梭子蟹的两种主要来源,本研究首先比较了池塘养殖与野生三疣梭子蟹可食部位(卵巢、肝胰腺、肌肉)的呈味核苷酸、游离氨基酸、滋味活度值和味精当量,然后采用电子舌对可食部位的整体滋味进行评价。结果表明,池塘养殖梭子蟹卵巢中核苷酸的滋味活度值显著高于(p<0.05)野生梭子蟹,池塘养殖梭子蟹卵巢中的IMP(肌苷5'-单磷酸)、GMP(一磷酸鸟苷)、AMP(一磷酸腺苷)显著高于野生梭子蟹(p<0.05),肝胰腺中的GMP和AMP、肌肉中的IMP均低于野生梭子蟹;池塘养殖三疣梭子蟹雌体肝胰腺、肌肉中的大部分游离氨基酸含量低于野生,卵巢中则相反,卵巢中的呈味氨基酸和必需氨基酸占总游离氨基酸百分比均高于野生三疣梭子蟹,其中,野生梭子蟹中的苦味氨基酸对整体滋味贡献度较大,池塘养殖梭子蟹中的苦/甜味氨基酸对整体滋味贡献较大。池塘养殖三疣梭子蟹卵巢中的味精当量(EUC值=53.94 g MSG/100 g)显著高于(p<0.05)野生梭子蟹卵巢(EUC值=15.81 g MSG/100 g),野生梭子蟹肝胰腺和肌肉中的EUC均高于池塘养殖个体;就不同组织而言,卵巢中的鲜味优于肝胰腺和肌肉。电子舌主成分分析表明池塘养殖与野生梭子蟹的肝胰腺滋味轮廓没有明显区别,但是卵巢与肌肉的整体滋味轮廓能够明显区分,且主要差异体现在第一主成分轴上。研究结果表明池塘养殖三疣梭子蟹卵巢整体滋味优于野生梭子蟹,野生雌体肌肉和肝胰腺的滋味优于池塘养殖个体,这些结果可为池塘养殖三疣梭子蟹的品质调控提供一定的理论指导。     

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。     

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     

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 acids in muscles and liver of Tunisian wild and farmed gilthead sea bream, Sparus aurata

The total fat content and the fatty acids profile were analysed in the dorsal and ventral muscles and in the liver from wild and farmed gilthead sea bream (Sparus aurata). The amount of fish lipid was higher in farmed than in wild fish in all studied samples and the highest level of all was observed in liver. It was noted that, among all the samples studied for saturated fatty acids (SFA) and Monounsaturated fatty acids (MUFA), whether farmed or wild, palmitic (C16:0) and oleic (C18:1 n − 9) acids were the principal saturated and monounsaturated fatty acids. The results showed that farmed fish contained a higher level of n − 3 polyunsaturated fatty acids (PUFA), particularly docosahexaenoic acids (DHA) and eicosapentaenoic acids (EPA), whereas wild fish contained a higher level of n − 6 PUFA. Arachidonic acid (C20:4 n − 6) was the primary n − 6 PUFA in wild fish whereas in farmed fish, linoleic acid (C18:2 n − 6) was the major n − 6 PUFA. Farmed fish were characterized by higher n − 3/n − 6 ratio for all samples studied, due to the abundance of n − 3 PUFA, particularly DHA.     

Polychlorinated biphenyls in salmon and salmon feed: global differences and bioaccumulation

Concentrations of 160 polychlorinated biphenyl (PCB) congeners or congener groups were determined in approximately 600 farmed Atlantic salmon from around the world and wild (ocean-caught) Pacific salmon from the Northeast Pacific. Concentrations and PCB congener profiles were analyzed to provide insight into the sources and uptake of PCBs in salmon as well as regional differences. Although total PCB concentrations in wild salmon appeared to be correlated to total lipid content, the increased proportion of total lipids in the farmed salmon could not account for the much greater PCB concentrations. We investigated the PCB congener patterns of hundreds of salmon samples using principal component analysis to further illuminate regional and species differences. Three major PCB patterns were observed, in most wild fish (except British Columbia and Oregon chinook), in farmed fish from the Atlantic, and in most farmed fish from the Pacific. The PCB congener profiles of farmed salmon often closely corresponded to a sample of commercial feed purchased in the same region, indicating that the feed is likely to be the major source of PCBs for farmed salmon. In such cases where PCB profiles in fish and feed were similar, a comparison of congener concentrations in fish and the feed showed that the majority of congeners, with some notable exceptions, were bioaccumulative to the same extent, irrespective of physical properties.     

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.     

Occurrence and human health risks of twenty-eight common antibiotics in wild freshwater products from the Xiangjiang River and comparison with the farmed samples from local markets

ABSTRACT

The occurrence of 28 common antibiotics in wild and farmed aquatic products from different species was comprehensively investigated in the present study. The results showed that a larger number of antibiotics could be detected quantitatively in wild samples, while the farmed samples had higher concentrations. Twenty, 17, and 14 target compounds were found in the muscles of wild molluscs, wild fish and farmed fish with total concentrations of 2.02–16.4 ng g^–1, 0.51–11.9 ng g^–1, and <LOD – 144 ng g^–1, respectively. Quinolones could be frequently detected in all investigated samples with higher concentrations, while sulphonamides were only detected more frequently in wild molluscs. For wild samples, sulfamethoxazole, sulphamethazine, clarithromycin, and ciprofloxacin are the main antibiotics that were detected in molluscs and fish with different residues. However, there was almost no significant residue difference among different wild fish. Compared with other studies in China or overseas, antibiotic residues in the investigated fish were almost always at a relative low level. Monte Carlo simulation showed that the farmed fish posed higher health risks than the wild fish, while the proportion of the consumers with chronic toxic risk (HI) of farmed fish higher than 0.05 (a distinct risk) was only 1.15 %.     

Quality of farmed and wild sea bass lipids studied by (1)H NMR: Usefulness of this technique for differentiation on a qualitative and a quantitative basis

Proton Nuclear Magnetic Resonance ((1)H NMR) spectroscopy was employed to study the lipids of farmed and wild European sea bass (Dicentrarchus labrax). This technique provided a great deal of detailed information on sea bass lipids composition and, once the spectra signals have been assigned, the simple observation of the spectra enables one to distinguish cultured from wild fish. This distinction is possible due to the presence in the former of high proportions of diunsaturated acyl groups, mainly linoleic. Furthermore, new approaches for quantitative characterization of sea bass lipids were developed. For the same season wild sea bass lipids contain not only higher molar percentages of omega-3 and of docosahexaenoic (DHA), but also higher concentrations of phosphatidylcholine and of cholesterol than farmed ones. However, in general, the absolute content of DHA and of eicosapentaenoic plus arachidonic (EPA+ARA) acyl groups as well as of phosphatidylcholine and cholesterol, were reasonably higher in farmed than in wild sea bass fillets, due to the higher total lipid content of the former. The presence of omega-1 acyl groups in all farmed samples and in some of the wild specimens was shown. As far as we know, this is the first time that omega-1 acyl groups have been identified and quantified in fish lipids by (1)H NMR.     

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.     

Comparative study of elemental content in farmed and wild life Sea Bass and Gilthead Bream from four different sites by FAAS and EDXRF

The purpose of this work is to compare the elemental content of samples of wild and farmed fish from four different Portuguese locations.     

Effects of different cooking methods on the mineral contents of wild and farmed sea bream (Sparus aurata)

The effects of different cooking methods (steaming, boiling, oven cooking, grilling, frying in olive oil, frying in soybean oil, frying in corn oil and frying in sunflower oil) on mineral contents (Ca, Mg, K, Na, Fe, Zn, Cu and Mn) of wild and farmed sea bream (Sparus aurata) were determined. The moisture rate decreased significantly (P < 0.05) after boiling, grilling, oven cooking and frying but remains stable after steaming. The fat content increased with different frying treatments. The Ca, Mg, Na, K and Zn contents of wild and farmed sea bream cooked by almost all methods significantly decreased (P < 0.05). The Cu content in grilled wild and farmed sea bream increased significantly (P < 0.05). Losses of mineral content in fried sea bream were higher than those of fish cooked by other methods. On comparing the raw and cooked fish, the results indicated that cooking had considerable effect on the mineral contents.