基于三文鱼介电特性的模拟食品研发

基于三文鱼的介电特性,以乳清蛋白粉为主要原料,研发适用于三文鱼微波巴氏杀菌的模拟食品。采用同轴探针法测定了20～110℃,频率300～2 500 MHz三文鱼的介电特性,分析模拟食品介电特性随乳清蛋白含量的变化,以此匹配三文鱼的介电特性。结果表明,温度一定时,三文鱼的介电常数和介电损耗均随频率的升高而减小;频率一定时,介电常数随温度的升高而减小,介电损耗随温度的升高而增大。乳清蛋白粉含量增加,模拟食品的介电常数和介电损耗均减小。模拟食品配方(质量分数)为10%乳清蛋白粉,1%结冷胶,1%D-核糖,1%L-赖氨酸,0. 3%CaCl_2,86. 7%蒸馏水时,在433、915、2 450 MHz频率下介电特性曲线和三文鱼接近,可以用于三文鱼微波巴氏杀菌温度分布和冷热点位置的确定,为三文鱼微波巴氏杀菌工艺开发提供了理论基础。     

时讯

<正>挪威三文鱼多次被检不合格近日,国家质量监督检验检疫总局公布了2015年6月进境不合格食品、化妆品信息,其中有两批挪威三文鱼被检出不合格,重量各为3吨左右。一批是厦门一公司进口的冰鲜鲑鱼(三文鱼)被检出霍乱弧菌,另一批是重庆一家公司进口的三文鱼被查出黄金色葡萄球菌,检疫部门对这两批次挪威三文鱼进行了销毁处理。而此前,检疫部门已多次在挪威三文鱼产品中检出鲑鱼贫血症(ISA)病毒。     

电子鼻结合GC-MS检测沙拉酱对挪威三文鱼风味的影响

为探究沙拉酱对三文鱼风味的影响,利用电子鼻技术结合顶空固相微萃取技术(HS-SPME)与气相色谱-质谱技术(GC-MS),对添加沙拉酱前后的三文鱼样品挥发性风味物质进行鉴定与比较。结果表明:通过感官实验分析,香甜味沙拉酱、原味沙拉酱与三文鱼食用比例分别确定为1:6、1:7时食品口感最佳,符合大多数人的感官需求。通过对电子鼻传感器响应值的分析比较及主成分分析得出,添加两种不同沙拉酱后三文鱼样品的醇醛类、碳氧化合物、有机化合物等物质均显著增加(P<0.05),添加沙拉酱前后的三文鱼样品具有较好的区分度,并且经GC-MS鉴定添加了沙拉酱以后三文鱼样品的醛酮类、醇类、酯类、酸类、烃类物质等含量显著增加(P<0.05),尤其是酯类和酸类物质的含量较多,检测结果与电子鼻分析结果较为一致。同时添加沙拉酱后检测三文鱼中的庚醛、己醛等腥味物质都有所降低,1-辛烯-3-醇未检测出,说明沙拉酱可以掩盖三文鱼某些腥味物质。综合来看,添加沙拉酱后不仅可以促进三文鱼食品整体风味物质的形成,还可以掩盖三文鱼中的腥味物质,从而进一步提高三文鱼食品的感官评分及营养价值。     

资讯

挪威 三文鱼将携"身份证"入口 沸沸扬扬的"假三文鱼事件"过后,挪威王国驻华大使馆渔业参赞在沪表示,为使上海市民吃到正宗挪威三文鱼,他们将考虑引入先进的可追溯系统,为每条挪威三文鱼制作"身份证"。媒体关于假三文鱼的报道为上海市民认识正宗的三文鱼起到了很好的作用。挪威王国驻华大使馆渔业参赞透露,挪威已经建立起一套食品安全管理的新型食品检测系统,并于今年启用。每条挪威三文鱼,甚至是每块鱼肉都带上自己的"身份证"腮夹,可据此进行信息查询。市民在购买到来自挪威的三文鱼后,可到指定的地点检验这条或这块鱼肉的来源,甚至可以查到这条鱼来自挪威的什么水域、哪个网箱、吃什么饲料长大、     

小识三文鱼

营养成分与保健作用来自大西洋冰海的挪威三文鱼,被誉为“冰海鱼皇”,它以柔嫩结实的肉质以及鲜艳诱人的色泽,越来越受到人们的喜爱。三文鱼除了是高蛋白、低热量的健康食品外,还含有多种维生素以及钙、铁、锌、镁、磷等矿物质,并且还含有丰富的不饱和脂肪酸。在所有鱼类中,三文鱼所含的Omega-3不饱和脂肪酸最多(每100克三文鱼约含27克),营养学研究证明,Omega-3不饱和脂肪酸能有效的降低高血压和心脏病的发病率,还对关节炎、乳腺癌等慢性病有益处,对胎儿和儿童的生长发育有促进作用。如何选购三文鱼我们用的三文鱼,大多来自挪威,有冰鲜和冷…     

挪威三文鱼进入主流中餐

今年美食趋势正在被绿色奥运理念所主导：追求健康、自然、高营养食物。挪威海产局官员欧诗娜女士说：“2008年挪威三文鱼在中国的销量骤增，得益于中国消费者对健康食品的追求。”     

健康食品知多少

美国最新选出了14种健康食品,即绿茶、三文鱼、菠菜、西兰花、大豆、番茄、坚果、燕麦、蓝莓、南瓜、柑橘、火鸡、酸奶、四季豆。由美国医学博士普拉特撰写的《超级食品:将改变你们生活     

英国对华食品出口激增 猪肉和三文鱼出口量翻番

正据英国《金融时报》3月24日报道,英国出口到中国的食品去年飙升了82%,其中猪肉和三文鱼出口几乎翻番。英国食品和软饮料出口到中国的总值从2012年的9200万英镑增加到2013年的超过两亿英镑,使中国成为欧盟市场之外最重要的英国食品出口市场。中国当局2011年批准英国猪肉和三文鱼进入中国市场,刺激了英国食品的出口。猪肉出口中国的数量上涨了92%,苏格兰三文鱼上涨了90%。英国食品饮料联合会的琼斯说:"中国对     

挪威三文鱼将携“身份证”入口

沸沸扬扬的“假三文鱼事件”过后．挪威王国驻华大使馆渔业参赞在沪表示．为使上海市民吃到正宗挪威三文鱼．他们将考虑引入先进的可追溯系统，为每条挪威三文鱼制作“身份证”。挪威王国驻华大使馆渔业参赞透露，挪威已经建立起一套食品安全管理的新型食品检测系统，并已启用。每条挪威三文鱼，甚至是每块鱼肉都带上自己的“身份证”腮夹，可据此进行信息查询。     

三文鱼肴三款

三文鱼,学名鲑鱼,产于挪威。入肴后味美细嫩,是一种倍受人们喜爱的海洋食品。随着人工养殖技术的进步与国内外交往的扩大,三文鱼肴已在国内一些餐厅酒楼露面。这里笔者制作出几款三文鱼肴,供您参考试烹。 金银三文鱼排 此菜是将三文鱼肉片成长方片,渍味、拍粉、粘蛋清糊,其一面沾上腰果仁末,经油炸制而成。具有一面金黄酥脆,一面洁白松软,鱼肉细嫩鲜香的特点。     

Lipid composition and contaminants in farmed and wild salmon

Levels of omega-3 (n-3) and omega-6 (n-6) fatty acids and lipid-adjusted concentrations of polychlorinated biphenyls (PCBs), dioxins, toxaphene, and dieldrin were determined in 459 farmed Atlantic salmon, 135 wild Pacific salmon, and 144 supermarket farmed Atlantic salmon fillets purchased in 16 cities in North America and Europe. These were the same fish previously used for measurement of organohalogen contaminants. Farmed salmon had greater levels of total lipid (average 16.6%) than wild salmon (average 6.4%). The n-3 to n-6 ratio was about 10 in wild salmon and 3-4 in farmed salmon. The supermarket samples were similar to the farmed salmon from the same region. Lipid-adjusted contaminant levels were significantly higher in farmed Atlantic salmon than those in wild Pacific salmon (F = 7.27, P = 0.0089 for toxaphene; F = 15.39, P = 0.0002 for dioxin; F > or = 21.31, P < 0.0001 for dieldrin and PCBs, with df = (1.64) for all). Levels of total lipid were in the range of 30-40% in the fish oil/fish meal that is fed to farmed salmon. Salmon, especially farmed salmon, are a good source of healthy n-3 fatty acids, but they also contain high concentrations of organochlorine compounds such as PCBs, dioxins, and chlorinated pesticides. The presence of these contaminants may reduce the net health benefits derived from the consumption of farmed salmon, despite the presence of the high level of n-3 fatty acids in these fish.     

Canned Salmon Curd Reduced by Use of Polyphosphates

Significant reduction of curd in canned salmon prepared from frozen fish was achieved. Prior to being placed in the can, salmon steaks or pieces were given dips of a few seconds to 2 min in sodium poly-phosphate in concentrations from 5% to saturated. Curd was effectively reduced in canned pink and sockeye salmon prepared from fish in frozen storage for up to a year, to a level at least equivalent to canned salmon prepared from fresh fish. Improvements in flavor and texture were noted. A simple scoring system is presented for evaluating canned salmon based upon visual scoring of curd present on the surface of canned product.     

Toxicokinetic model assessment on the dechlorination of dietary toxaphene CHB-62 into CHB-44 in Atlantic salmon (Salmo salar L.)

European Union legislation on the upper limits of toxaphene in feed and food include the congeners CHB-26, CHB-62 and CHB-50 and is set at 50 µg kg^?1 feed for the sum of these three congeners. However, due to their elevated presence in fish, the congeners CHB-40 and CHB-41, CHB-44, and CHB-42 should also be included according to the European Food Safety Authority (EFSA) in 2005. Earlier trials with model zebra fish have shown in vivo dechlorination of dietary CHB-62 to CHB-44 and, to a lesser degree, of CHB-50 to CHB-40. Biomagnification patterns of Atlantic salmon, fed with technical toxaphene-enriched feeds, indicated that Atlantic salmon have a similar dechlorination. In the present study, a serial one-compartment physiological kinetic model, which includes differentiated growth of body components, is used to quantify the contribution of dechlorination to the congener-specific fillet accumulation of a mixture of dietary toxaphene congeners in Atlantic salmon. The model is assessed from experimental uptake and elimination kinetics of Atlantic salmon smolt fed with technical toxaphene for 122 days followed by a depuration period of 75 days in which the fish were fed toxaphene-free control feed. The serial one-compartment model shows that about 31% of CHB-44 that accumulated in the fillet originated from dietary CHB-62. In contrast, dechlorination of CHB-50 into CHB-40 is not significant. The results show that previously demonstrated in vivo dechlorination of CHB-62 into CHB-44 in zebra fish also occurs in the farmed fish species Atlantic salmon. This dechlorination can at least partly explain the relatively elevated CHB-44 observed in toxaphene fish surveys.     

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.     

Fate of chlorinated fatty acids in migrating sockeye salmon and their transfer to arctic grayling

To investigate whether biotransport constitutes an entry route into pristine ecosystems for nonpersistent, nonvolatile xenobiotic compounds, extractable organically bound halogen in sockeye salmon (Oncorhynchus nerka) from Alaska was determined before and after spawning migration. The major organohalogen compounds in the salmon were halogenated fatty acids, predominantly chlorinated species that accounted for up to 35% of the extractable, organically bound chlorine (EOCl) in the fish tissues. The amount of chlorinated fatty acids in the salmon muscle decreased as a result of spawning migration. The decrease was correlated with that of triacylglycerols in the salmon muscle, indicating the chlorinated fatty acids to be mobilized and metabolized to approximately the same extent as the other fatty acids. Chlorinated fatty acids were also transferred to the maturing roe in a manner similar to that of the unchlorinated fatty acids. Lipids of the Arctic grayling (Thymallus arcticus), a fish resident to the spawning lake of the salmon, contained higher concentrations of chlorinated fatty acids than grayling in a lake without migratory salmon. This may reflect a food-chain transfer of the chlorinated fatty acids originating from the salmon, demonstrating a long-range transport route for this type of pollutants to pristine areas.     

Relation of smoking parameters to the yield,colour and sensory quality of smoked Atlantic salmon (Salmo salar)

The relations between smoking parameters and the characteristics of salmon raw material were investigated with respect to yield, colour, flesh content of phenol and salt, and sensory properties. The fish studied were ocean ranched salmon harvested in Iceland in July 1998 and farmed salmon from Norway slaughtered in October 1998 and April 1999. Seven treatments were applied on fresh or frozen raw material combining dry or brine salting with cold smoking at 20 or 30°C. Electrostatic smoking was tested on dry-salted salmon fillets. The results show a lower yield after filleting and trimming with ocean ranched fish. Although freezing had little effect on yield, total loss was slightly greater, especially for fish with low fat content. Sensory differences were also apparent. The brine salting technique resulted in lower losses. Fish with higher fat content gave a better yield after processing, although careful control of the smoking procedure was required (especially at 30°C) to avoid a case-hardening effect. With brine salting, salt uptake was higher for smaller, leaner fish. The phenol content of flesh depended on the technique and/or smoking temperature used, regardless of the fish studied. However, for a smoking temperature of 30°C, the flesh of smaller, leaner fish showed a higher phenol level. Smoking conditions and preliminary treatment such as freezing produced similar differences in sensory characteristics, regardless of the fish studied, although smaller, leaner individuals appeared to be more sensitive to these processes.     

Investigation of selected persistent organic pollutants in farmed Atlantic salmon (Salmo salar), salmon aquaculture feed,and fish oil components of the feed

There is extensive literature documenting the bioaccumulation of persistent organic pollutants in the marine environment, but relatively little data are available on contamination pathways in aquaculture systems such as that for farmed salmon. In recent years,the salmon industry has grown significantly in Europe. This study reports on the determination of a wide range of polychlorinated biphenyls (PCBs), organochlorine pesticides, and polybrominated diphenyl ethers (PBDEs) in farmed and wild European Atlantic salmon fish, aquaculture feeds, and fish oils used to supplement the feeds. The study confirms previous reports of relatively high concentrations of PCBs and indicates moderate concentrations of organochlorine pesticides and PBDEs in farmed Scottish and European salmon. Concentrations of the selected persistent organic pollutants varied among the samples: PCBs (salmon, 145-460 ng/g lipid; salmon feeds, 76-1153 ng/g lipid; fish oils, 9-253 ng/g lipid), S DDTs (salmon, 5-250 ng/g lipid; salmon feeds, 34-52 ng/g lipid; fish oils, 11-218 ng/g lipid), and PBDEs (salmon, 1-85 ng/g lipid: salmon feeds, 8-24 ng/g lipid; fish oils, ND-13 ng/g lipid). Comparison of the samples for all groups of contaminants, except for HCHs, showed an increase in concentration in the order fish oil < feed < salmon. Homologue profiles were similar, with an increase in contribution of hepta- and octa-PCBs in the fish, and profiles of DDTs were similar in all three types of samples. With a constant contribution to the total PCB content, the ICES 7 PCBs appear to be reliable predictors of the PCB contamination profile through all the samples. For PBDEs, BDE 47 dominated the profiles, with no significant difference in the PBDE profiles for the three matrixes. Samples with higher PCB contents generally showed higher levels of the pesticide residues, but this was not the case with the PBDEs, indicating the existence of different pollution sources.     

Bromophenol Distribution in Salmon and Selected Seafoods of Fresh- and Saltwater Origin

Analysis of saltwater Pacific salmon (Onchorynchus sp.) showed that sufficient concentrations of bromophenols were present in saltwater salmon to provide sea-, brine-, or iodine- like flavor notes, but the compounds were virtually absent in spawning run ocean and prime condition Great Lakes freshwater salmon. Octanol/water partition coefficients revealed that bromophenols would be readily absorbed by fish from the diet. Analysis of marine fish, crustaceans, and molluscs also revealed notable concentrations of bromophenols in all samples. Only sporadic, low concentrations of bromophenols were found in freshwater fish. The data support the hypothesis that simple bromophenols are widely distributed in marine species via the food chain.     

Effect of Fish and Oil Nature on Frying Process and Nutritional Product Quality

ABSTRACT: The modifications on a lean fish (cod—Gadus morhua) and a fatty fish (farmed salmon—Salmo salar) after the application of pan-frying using 2 types of oil with different lipid profile (extra virgin olive oil and sunflower oil) was the aim of this study. Fat content and total energetic value increased significantly after the frying process only in the lean fish, without relevant changes in the fatty fish. Extra virgin olive oil led to a higher fat absorption rate than sunflower oil in both fish. Frying hardly affected the lipid profile of farmed salmon regardless the oil used, however it drastically changed in fried cod compared to raw cod. Omega-6/omega-3 ratio increased from 0.08 in raw cod to 1.01 and 6.63 in fried cod with olive oil and sunflower oil, respectively. In farmed salmon, the omega-6/omega-3 ratio was 0.38 (raw), and 0.39 to 0.58 in fried salmon. The amount of EPA + DHA slightly decreased with frying in salmon, and increased in cod. The type of oil has more influence in the nutritional fish quality for the lean fish compared to that of the fatty fish. The use of extra virgin olive oil was efficient to avoid a significant increase of the lipid oxidation intensity during frying in cod but not in salmon. Practical Application: Food modifies its composition and nutritional value with the application of cooking technologies. As most food table composition tables are based on raw food products, this article contributes with interesting data on pan-fried fish composition, which may improve the approach to achieve a real intake of healthy nutrients as omega 3 fatty acids.     

Rapid quantitative detection of, Listeria monocytogenes in salmon products: evaluation of pre-real-time PCR strategies

The spread and persistence of Listeria monocytogenes in smoked fish products and seafood processing factories are big concerns. Thus, the corresponding quality assurance programs must include adequate microbiological control measures. We evaluated eight different pre-PCR sample processing strategies to be coupled with a previously developed real-time PCR assay for the quantitative detection of L. monocytogenes in salmon products. The optimal pre-PCR procedure involved filtration and DNA purification with the use of a commercial kit. This strategy could detect 10 CFU of L. monocytogenes per g of smoked salmon and could quantify 1,000 CFU/g with excellent accuracy compared with the standard plate count method. Thus, this method could be a promising alternative for the quantitative detection of L. monocytogenes in smoked fish products and processing factories. This method could also detect the bacterium in raw salmon.