谷氨酰胺转胺酶的特性及其在食品工业中的应用

谷氨酰胺转胺酶可以催化蛋白质分子内或分子间的酰基转移反应，通过形成的交联键改善蛋白质的功能性质。本文介绍了谷氨酰胺转胺酶的作用机理及谷氨酰胺转胺酶在食品工业中的应用。     

谷氨酰胺转胺酶特性及其在肉制品中的应用

谷氨酰胺转胺酶可以催化蛋白质分子内或分子间的酰基转移反应,通过形成的交联键改善蛋白质的功能性质。本文介绍了谷氨酰胺转胺酶的特性、作用机理及其在肉制品中的应用。     

谷氨酰胺转胺酶的功能特性及在动物性食品中的应用研究

谷氨酰胺转胺酶可以催化蛋白质分子内或分子间的酰基转移反应,通过形成的交联键改善蛋白质的功能性质。本文主要介绍了谷氨酰胺转胺酶的作用机理、功能特性及其在动物性食品加工业以及开发新型食品中的应用。     

谷氨酰胺转胺酶及其在食品加工中的应用

谷氨酰胺转胺酶(Transglutaminase)又称转谷氨酰胺酶,是一种催化蛋白质或多肽链中的谷氨酰胺残基里的γ—酰胺基和一级氨基之间进行酰胺基转移反应的酶。经研究表明谷氨酰胺转胺酶广泛存在于动、植物以及微生物机体组织中,其主要生理作用有:作为血液凝固的第13因子促进凝血作用,参与伤口的愈合过程;促使表皮细胞在分化末期中形成角质层;参与毛囊蛋白质的架桥;促进胰岛素的分泌,诱导细胞分化,催化介导细胞的凋亡或程序化死亡;以及识别癌变细胞组织等等,在机体多种生化反应及生命代谢过程中发挥着重要的作用。由于谷氨酰胺转胺酶具有在蛋白质…     

谷氨酰胺转胺酶的功能性质及在乳制品中的应用

介绍谷氨酰胺转胺酶的国内外研究现状,阐述其理化性质、来源及其在乳制品中的应用.特别是谷氨酰胺转胺酶在液态奶中对蛋白质、乳清蛋白及酪蛋白的影响和对酸奶品质的改良作用.     

谷氨酰胺转胺酶理化性质及在乳品中的应用

谷氨酰胺转胺酶是一种催化酰基转移反应的转移酶,它可使蛋白分子间和分子内产生共价交联反应,从而改善食品蛋白质的功能特性。本文主要论述了谷氨酰胺转胺酶的理化性质、作用机理以及它在乳品加工中的应用。     

谷氨酰胺转胺酶的性质及在食品中的应用

谷氨酰胺转胺酶是一种催化酰基转移反应的转移酶,它可使酪蛋白、肌球蛋白、谷蛋白和乳球蛋白等蛋白质分子之间产生交联,从而改变食品蛋白质的功能性质。本论述了谷氨酰胺转胺酶的性质及在食品开发中的应用。     

微生物谷氨酰胺转移酶及其在食品工业中的应用

谷氨酰胺转移酶能促进蛋白质分子间的交联作用,催化蛋白质之间异肽键的形成,对蛋白质溶解度、乳化能力、发泡性能和凝胶化作用等功能产生积极影响。众多食品工业加工过程中如奶酪生产、乳制品加工、肉类加工、焙烤制品及可食性膜的生产过程等都应用了这种酶的交联特性。微生物源性的谷氨酰胺转胺酶在生物技术生产中所需成本低,目前已经应用于几乎所有的工业领域。本文总体概述了谷氨酰胺转胺酶的特点及其在食品工业中的应用。     

微生物谷氨酰胺转胺酶的应用进展

谷氨酰胺转胺酶是一种催化酰基转移反应的转移酶,它可使酪蛋白、肌球蛋白、谷蛋白和乳球蛋白等分子之间产生交联,改变蛋白质的功能性质,简述了谷氨酰胺转胺酶在食品应用的一些最新进展。     

谷氨酰胺转胺酶的用量和腌制时间对蛋白质凝胶特性的影响及其在西式火腿加工中的应用

主要研究谷氨酰胺转胺酶在低温腌制过程中对蛋白质凝胶特性的影响。以西式蒸煮火腿为试验对象,通过测定不同添加水平的谷氨酰胺转胺酶在不同腌制时间段对产品的pH值、TPA质构特性、色差和扫描电子显微镜照片(SEM)的影响,结合感官评定的分析结果,初步探讨西式火腿低温腌制条件下谷氨酰胺转胺酶的应用工艺。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the