微生物源食品防腐剂在调味品中的应用

随着人们生活水平的提高,越来越多的消费者追求绿色食品,因此探索天然产物作为食品防腐剂已成为研究热点。文章根据调味品行业天然防腐剂的发展需求,有针对性地论述了3种常见微生物源食品防腐剂(乳酸链球菌素、聚赖氨酸和纳他霉素)的理化性质、抑菌机制和抑菌特性。同时,分析了3种微生物源食品防腐剂在调味品中的研究现状,并展望了其在调味品行业中应用的可行性以及其可能成为调味品行业天然防腐剂的发展趋势。     

新型植物源天然食品防腐剂及其抑菌性能

食品发生腐败变质会造成巨大的经济损失,目前常采用的防腐措施就是添加食品防腐剂.食品防腐剂是食品加工、贮藏过程中必不可少的添加剂,要求具有无毒、少残留、高效、对人体无害等特点.食品防腐剂分为化学防腐剂、天然防腐剂和复合型防腐剂.天然食品防腐剂按其不同的来源又可分为植物源天然防腐剂、动物源天然防腐剂以及微生物源天然防腐剂等类型.天然植物源食品防腐剂由于其本身的优越性,越来越受到人们的青睐.本文主要对六种新型植物源天然食品防腐剂 (即香辛料提取物、中草药提取物、芦荟提取物、竹叶提取物及荸荠皮提取物) 的抑菌成分、抑菌机理和抑菌性能等进行了较为详尽的论述.旨在为我国新型、安全、高效、天然植物源食品防腐剂的研究和开发提供参考.     

新型微生物源天然食品防腐剂及其抑菌性能

天然食品防腐剂按其来源的不同可分为植物源天然防腐剂、动物源天然防腐剂以及微生物源天然防腐剂等类型.天然微生物源食品防腐剂由于其本身的优越性,越来越受到人们的青睐.本文主要对五种新型微生物源天然食品防腐剂(即乳球菌肤、溶菌酶、聚赖氨酸、苯乳酸及曲酸)的理化特性、抑茵机制和抑茵特性等进行了概括和论述.旨在为我国新型、安全、高效、微生物源天然食品防腐剂的研究和开发提供参考.     

动物性天然食品防腐剂的研究进展

随着生活水平的不断提高和对健康的日益关注,人们对食品防腐剂的安全性提出了更高的要求.天然食品防腐剂一般是指从植物、动物、微生物中直接分离提取的,具有防腐作用的一类物质,具有资源丰富、抗菌性强、水溶性好、安全无毒、抑菌谱广等优点,近年来成为食品保鲜防腐领域的研究热点.但是,目前天然食品防腐剂的实际使用并不多,天然食品防腐剂的研究与开发仍存在很多问题.本文主要介绍了5种动物性来源的抑菌物质,阐述了它们作为天然食品防腐剂的理化性质、抑菌机理和应用现状,并针对天然食品防腐剂在研究和应用中所遇到的问题,对天然食品防腐剂的发展方向进行了分析和讨论.     

新型微生物源天然食品防腐剂的抑菌效果分析

为研究新型微生物源天然食品防腐剂的抑菌效果,取大肠杆菌和金黄色葡萄球菌分别接种在含不同质量浓度的乳酸链球菌肽、溶菌酶的液体培养基中培养18 h;然后对其OD值进行测量,分析三种新型微生物源天然食品防腐剂的抑菌效果。根据实验结果,防腐剂乳酸链球菌肽、溶菌酶对两种菌均有较高的抑制效果。     

天然食品防腐剂及其在食品中的应用研究

食品防腐剂是指为提高食物的色、香、味,或者为延缓由微生物、酶解和氧化引起的食品降解,而添加到食物中的天然物质或化学合成物质。在食品工业中,常用的防腐剂主要为化学合成防腐剂,由于人们食品安全意识的逐步提高,以及化学合成防腐剂对人体健康存在潜在的风险及隐患,消费者对于化学防腐剂的安全性一直存在顾虑。相比之下,天然防腐剂因其抑菌效果好、绿色天然和无毒性的特点越来越受到人们的青睐,消费者对天然防腐剂的需求也日益增加。因而天然防腐剂已然成为当下的研究热点,并且在当今食品行业已得到广泛的研究和应用。文章综述了植物、动物和微生物等不同来源的天然防腐剂及其在食品中的应用,以提高食品质量,延长食品保质期。     

7种天然防腐剂对气调包装酱卤肉制品的抑菌效果

以气调包装卤鸭脖、卤鸭翅为研究对象,采用选择性培养基对腐败菌进行分离,通过测定抑菌率,比较研究了7种天然食品防腐剂:天然食用香料、香辛料、发酵醋-01、果蔬汁、复配防腐剂-01、复配防腐剂-02和醋粉-02的抑菌效果。结果表明,卤鸭脖的优势腐败菌为乳酸菌、微球菌、大肠菌群;卤鸭翅的优势腐败菌为乳酸菌、酵母菌、大肠菌群。7种防腐剂对以上腐败菌均有一定的抑菌效果,综合分析抑菌效果由高到低为:发酵醋-01>香辛料>醋粉-02>复配防腐剂-01≈复配防腐剂-02≈天然食用香料≈果蔬汁。通过比较以上防腐剂对不同产品总微生物的抑菌效果,发现除发酵醋-01(抑菌率均为100%)外,其余6种天然防腐剂对卤鸭翅的抑菌效果优于卤鸭脖。     

微生物食品防腐剂的研究与应用现状

近年来出现的多起因化学合成防腐剂不规范添加所引起的食品安全事件,引起了国内外学者的广泛重视。对于某些常见食品添加剂引起的中毒,致病,致癌的可能性的不明确,也令人担忧。因此迫切需要一种真正天然并且安全的食品添加剂。微生物防腐剂是利用生物工程技术分离、提取的具有抑菌防腐作用的微生物及其代谢产物,是一种安全无毒,天然高效的食品防腐剂。微生物防腐剂的研究与应用已成为了中外各国科学家投入大量精力的新兴研究课题。笔者对天然防腐剂中的微生物防腐剂的抑菌广谱、防腐机理、研究和应用进行了综述,如乳酸链球菌、纳他霉素、ε-聚赖氨酸、溶菌酶、红茶菌、红曲和纳豆菌等,以期为其他研究人员提供一定的参考,同时对各种微生物防腐剂今后的研究和发展方向提出了建议。     

微生物防腐剂及其在食品工业中的应用

微生物防腐剂是一类由微生物产生的能杀死或抑制微生物生长的天然、安全、高效的食品防腐剂。本文阐述了微生物防腐剂的来源、分类、结构特性、抑菌机制及其在食品工业中的应用和发展前景。     

天然防腐剂的应用研究进展

天然食品防腐剂是从生物体内提取加工而成的物质,其来源天然,或本身即为食品的组分,具有安全、高效的防腐特性。分别介绍了几种微生物来源、动物来源及植物来源的天然新型防腐剂的特性及其在食品工业中的应用研究,并指出了目前天然防腐剂的应用缺陷及发展前景,为其进一步的深入研究和综合开发利用提供一定的参考。     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.