DNA barcoding for the species identification of commercially important fishery products in Indonesian markets

The DNA barcoding approach was used for the species identification of 44 Indonesian commercial fishery products. Additionally, the intronless nuclear rhodopsin gene fragment (RH1) was added to the analysis to enable the identification of species not yet barcoded and possible hybrids. The 655‐bp cytochrome C oxidase subunit I (COI) gene fragment marker was successfully amplified and used to identify 86% of the total fish samples at the species level using the BOLD and BLAST public databases. Moreover, the RH1 marker was used to complete COI analysis. For a number of fish species, the COI sequences (six species) and RH1 sequences (eight species) were the first entries submitted to GenBank. This study demonstrated that COI barcoding is a promising tool for Indonesian fishery products and confirmed that it could be adopted in the future for regular seafood control as part of the Indonesian integrated food traceability system.     

肉制品掺假鉴别技术研究进展

肉制品在食品消费中占很大比例,近年来,肉制品掺假问题日益严重,肉制品掺假鉴别和溯源分析成为研究热点。传统的通过感官及形态的肉类鉴别方法已经不能满足肉类掺假鉴别的需要。随着现代分析仪器和生物技术的发展,多种蛋白质分析法、DNA分析法和无损检测方法日趋成熟。基于蛋白质的检测方法,如免疫分析法和色谱分析法均可定量检测,但不适用于加工肉制品。基于样品特征光谱的无损检测方法操作简单,检测时间短,具有独特的优势。基于DNA的检测方法,特别是荧光定量PCR方法具有检测灵敏度高,结果重复性好等优势,将成为未来肉类物种鉴别的发展方向,具有很好的应用前景。     

鱼胶基原鱼种鉴定技术研究进展

鱼胶作为我国传统滋补药材,近年来其消费市场日益繁荣,鱼胶基原鱼种来源范围不断扩大,尤其是进口基原鱼种占比不断提升,部分市售鱼胶真伪难辨,鱼胶基原鱼种鉴定需求不断增加。本文概述了鱼胶基原鱼种形态学鉴定法、光学分析法和分子生物学鉴定法的发展历程、应用情况,对比了分子生物学方法中不同基因片段、不同引物等的适用性,分析了上述方法的优缺点。传统形态学鉴定具有快速、不需要鉴定人员具备较高实验操作能力的优势,但依赖专家个人经验和观察手段,且对鱼胶残片等形态特征缺失的样品鉴定能力有限;光学分析法无法精确到种属;而以DNA条形码技术为主的分子生物学方法是对某一特定区域的DNA序列排列顺序进行对比分析,鉴定结果准确,但较为耗时。由于鱼胶是动物组织干制品,在物种鉴定方面具有形态信息较少、样品处理时间较长等特点;本文有针对性地综合国内外相关研究,填补了特殊动物组织物种鉴定研究方法综述的空白,为以后进口贸易或市场监管中如何优化鉴定技术提供理论依据。     

肉及肉制品掺假鉴别技术研究进展

近年来,随着市场对肉类产品需求的逐渐增加,肉类掺假事件时有报道,不仅扰乱了经济秩序,而且危害人们的身体健康。目前对肉制品掺假进行定性定量鉴别的检测技术主要包括基于蛋白质的酶联免疫吸附(enzyme-linked immunosorbent assay,ELISA)技术、基于代谢物的红外光谱(infrared spectroscopy,IR)技术和基于核酸的聚合酶链式反应(polymerasechain reaction,PCR)技术。基于核酸的检测技术,尤其是等温扩增技术、数字PCR技术具有快速、灵敏、简便、高效等优势,将成为未来肉类物种鉴别的发展方向,具有良好的应用前景。本文综述了肉及肉制品掺假鉴别技术的应用与特点,并深入探讨了其发展趋势,期望为肉类食品安全检测提供理论参考。     

Authentication of species in meat products by genetic techniques

In the present work, a method for the authentication of meat products was developed, using Polymerase Chain Reaction (PCR) followed by Forensically Informative Nucleotide Sequencing (FINS). This study describes the use of sequencing of the cytochrome b gene of the mtDNA in a wide variety of species to diagnose adulteration of meat through the substitution from one species to another that have less commercial value. The main importance of this work is to deal with a wide variety of species that have not previously been analyzed. This methodology strategy allows the authentication of meat species in all kind of products, fresh, or precooked products, the more usual format for marketing in that species. This method shows a specificity of 100%. The developed methodology was validated and finally applied to 20 commercial samples including some that had been subjected to intensive thermal treatment. In 15% of the products analyzed, the name of the species displayed in the label was not in agreement with the identified species. The main novelty of this work lies in the fact that it allows the identification of a large number of meat species not analyzed so far in previous works. In this work are included meat species, which can be easily found in our markets, and a wide variety of others whose consumption is common in other parts of the world. Therefore, this technique can be used as a routine method to avoid the mislabeling in the marketing of these products and to assess their correct traceability.     

生物传感器在水产品食用安全品质探制中的应用

主要就生物传感器在水产品质量监督及安全控制中的应用进行了综述,包括对于主要生化质量指标的评定,以及来自于环境的安全危害因子的监测,并就目前存在的问题及今后的发展趋势作了分析.     

PCR-based fingerprinting techniques for rapid detection of animal species in meat products

A reproducible, rapid, and simple method for simultaneous identification of multiple meat species in a single step DNA-based test has been developed based on the generation of species-specific fingerprintings by two different arbitrary DNA amplification approaches (RAPD- and AP-PCR). Samples representative of various species and meat products submitted to different processing conditions were selected to verify the applicability of the techniques. RAPD-PCR fingerprintings allowed the discrimination amongst pork, beef, lamb, chicken and turkey in all cases. Samples corresponding to each species were clustered together at similarity levels ?75%. The DNA profiles consisted of a discrete but reproducible number of bands, which made possible the interpretation of the results by simple visual inspection. AP-PCR also allowed identification of the five tested species in every sample although more complex patterns were generated, including some low intensity bands. In both cases, a ramp time between annealing and extension temperatures was introduced to achieve good reproducibility. Overall, the simplicity of RAPD-PCR patterns could make this technique suitable for meat authentication in routine analysis.     

ELISA-test for cooked meat species identification on gelatine and gelatine products

The results of the ELISA-test with a commercial cooked meat species identification kit on gelatine and gelatine containing products can be influenced by different gelatine types and concentrations leading to false positive readings. The test cannot be applied especially to meat products containing relatively high amounts of soluble collagens because their extracts form solid gels in the test wells. In this case the different reagents added will penetrate the gels and react with each other. The kit may not speciate reliablely commercial gelatine in isolation or in products where gelatine is the sole animal protein source.     

A novel method for species identification in milk and milk-based products

This study describes a method for species-specific detection of animal DNA from different species (cattle, sheep, goat, water buffalo) in milk and dairy products. A primer set was designed in conserved region on the basis of the alignment of the sequence codifying the genomic kappa-casein gene in order to amplify all four species with a single primer pair. Polymorphisms were detected via minisequencing with extension primers designed in conserved sequences for haplotype determination that allow unambiguous assignment to each species. The method was successfully applied to the detection of raw and pasteurized milk from the four different species considered as well as to cheese products from the retail trade. Estimation of the limit of detection was carried out using a progression of dilutions of genomic DNA as well as DNA isolated from milk of a known number of somatic cells from different species in order to be able to achieve detection rates as low as 0.1% bovine milk mixed with buffalo milk.     

肉及肉制品分子生物学鉴别技术研究进展

2013年初随着欧洲"马肉丑闻"这一食品安全事件的发生,食品掺假这一全球性问题引发了公众对食品安全的担忧以及各国政府的关注。用于食品真伪鉴别的分子生物学技术包括经典的普通PCR技术、实时定量PCR技术,以及近年来逐步发展起来的分子指纹技术等。此外,基因芯片技术、多重PCR技术等可提高检测通量的新型技术近年来也得到了长足发展。随着分子生物学技术向着高灵敏度、高通量的方向发展的同时,用于样品初筛的具有较高灵敏度和准确度的现场快速检测方法和检测设备的开发也将成为未来食品真伪鉴别的研究热点之一。本文对分子生物学技术在肉及肉制品真伪鉴别的应用和研究进展进行了综述。     

Species identification of formed fishery products and high pressure-treated fish by electrophoresis: a collaborative study

The suitability and reliability of three electrophoretic methods of fish species identification, urea isoelectric focusing (IEF), sodium dodecyl sulfate poly-acrylamide gel electrophoresis (SDS-PAGE) and native IEF, were evaluated on formed fish fillets and high pressure fish flesh by a collaborative study among four institutes. By following optimized standard operation procedures, the protein patterns of processed fish were compared to patterns of raw reference samples. The method to use depended of the effect of processing on the protein pattern. The proteins obtained from formed products were not denatured and therefore any of the three methods proved to be adequate, with a preference for native IEF which had a better discriminatory power for the species used. The high pressure process altered the proteins, and so only urea IEF and SDS-PAGE methods could be used. For these products, the chosen method should then be the one with the better discriminating power for the species being examined.     

Validation of a PCR-RFLP based method for the identification of salmon species in food products

The use of a PCR-RFLP based method for the identification of salmon species in food products was investigated. The reliability and practicality of the method was tested by a collaborative study in which five European laboratories participated. Two unknown samples (a commercial product of known species composition and a mix of two salmon species) required identification by comparison with authentic reference species. From a total of 50?cases, 100% of authentic species were correctly assigned, with all unknown samples also correctly identified. A larger scale analysis of UK commercial products was also performed spanning the whole range of salmon products available. In almost all cases the salmon species declared was confirmed, although, a trout species was detected in one product declaring only the presence of salmon. The investigation confirms the reproducibility of the method in different laboratories, and its applicability for commercial product analysis.     

Listeria in tropical fish and fishery products

Listeria monocytogenes is considered to be a ubiquitous organism occurring in both terrestrial and aquatic habitats. This organism has been isolated from fish and fishery products from different parts of the world and interestingly the incidence rate reported from tropical fish is rather low. Varying methodologies have been used by different investigators to study the incidence of L. monocytogenes in fish. Data on virulence of seafood-associated strains are lacking. For quality assurance in the fish processing industry, rapid and sensitive methods for the detection of L. monocytogenes are required.     

天然水产滋味类产品概述

主要介绍了天然水产滋味类产品的原料、生产工艺、产品特性及其在食品工业中的应用。     

鱼类冷冻调理食品生产工艺

概述了鱼类冷冻调理食品的特点和现状,并以冷冻调理鲐鱼及冷冻调理鳗鱼的生产过程为例详细介绍了鱼类冷冻调理食品的生产技术工艺。     

Determination of the formaldehyde content in fishery products

Summary The influence of external factors, such as storage temperature and time on the content of free formaldehyde (FA) in fishery products is described. On the basis of the examination of several methods for the determination of free and bound FA, the following procedures are recommended: (1) for measuring free FA, the samples are extracted using 6% perchloric acid at room temperature and the FA content of the extracts is measured by the formation of 3,5-diacetyl-1,4-dihydrolutidine; (2) bound, acid-labile FA is released by steam distillation using 1% sulphuric acid, giving a pH value of about 1. The FA content of the distillates may be determined either by chromotropic acid assay or by the method described for the extracts.

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Bestimmung des Formaldehydgehaltes in Fischprodukten

Zusammenfassung Es wird aufgezeigt, von welchen äußeren Einflüssen (z. B. Lagertemperatur und -zeit) der Gehalt an freiem Formaldehyd in einem Fischprodukt abhängt. Nach Überprüfung verschiedener Methoden zur Bestimmung des freien und gebundenen Formaldehyds werden folgende Verfahren vorgeschlagen: 1. Zur Messung des freien Formaldehyds wird die Probe mit 6%iger Perchlorsäure bei Raumtemperatur extrahiert; der Formaldehydgehalt des Extraktes wird über die Bildung von 3,5-Diacetyl-1,4-dihydrolutidin ermittelt. 2. Gebundener, säurelabiler Formaldehyd wird durch Wasserdampf-Destillation einer mit 1%iger Schwefelsäure versetzten Probe freigesetzt; der pH-Wert des Ansatzes beträgt etwa 1. Im Destillat kann Formaldehyd entweder über die Bildung des Lutidinfarbstoffes oder mit Chromotropsäure bestimmt werden.

     

Determination of the heating temperature of fishery products

Summary The German Fish Directive prescribes that products must be heated to the core temperature of +70° C to kill existing larvae of nematodes. For subsequent determination of the heating temperature samples were extracted with water. The extracts were analysed for protein content, for protein patterns obtained by isoelectric focusing and by using the coagulation test. The suitability of these methods was investigated with heated extracts, heated minced fish flesh, and smoked herring and mackerel. Smoking was performed in the kiln of the institute at controlled temperatures. Analysis of commercial samples showed that the core temperature during smoking of herring and mackerel must have been clearly below 70° C in several cases.

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Bestimmung der Erhitzungstemperatur von Fischereiprodukten

Zusammenfassung Die deutsche Fischverordnung schreibt vor, daß zum Abtöten eventuell vorhandener Nematodenlarven eine Kerntemperatur des Produktes von mindestens +70 °C erreicht werden muß. Zur nachträglichen Bestimmung der Erhitzungstemperatur wurden wäßrige Extrakte erhitzter Proben folgenden Analysen unterzogen: 1. Bestimmung des Proteingehaltes; 2. Flockungstest; 3. Isoelektrische Focussierung. Die Eignung dieser Methoden wurde mit erhitzten Extrakten und Proben aus zerkleinertem Fischfleisch sowie mit Heringen und Makrelen, die bei definierten Temperaturen geräuchert wurden, geprüft. Die nachfolgende Analyse von Handelsware ergab, daß bei mehreren Proben die Kerntemperatur bei der Räucherung deutlich unterhalb von 70 °C gelegen haben mußte.

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Part of this work was presented at the 21^st Annual Meeting of the Western European Fish Technologists Association (WEFTA) in Copenhagen on 25 August 1991