乳酸菌细菌素和超高压联合处理对低温切片火腿的防腐保鲜效果

为了揭示乳酸菌细菌素和超高压联合处理对低温切片火腿的防腐保鲜效果,并探讨乳酸菌细菌素和超高压联合处理在低温肉制品防腐保鲜应用中的可行性,在不添加任何化学防腐剂的情况下,分别以乳酸菌细菌素(enterocin LM-2)添加量320AU/g、600MPa超高压处理5min以及两者联合处理低温切片火腿,考察联合处理对样品中微生物数量、理化指标以及感官特性的影响。结果表明：enterocin LM-2和超高压技术的联合使用可明显延长低温切片火腿的货架期,有效减少贮藏过程中挥发性盐基氮的生成及脂肪氧化,并保持产品原有色泽、气味、质构等感官特性。综合微生物和理化特性分析结果,联合处理组的防腐效果最好,可将低温切片火腿的货架期延长至100d。     

乳酸菌细菌素研究进展及其在肉制品防腐保鲜领域的应用

乳酸菌细菌素是一种天然的生物防腐剂,可以抑制或杀灭食品里致病微生物和腐败微生物从而保证食品安全。文中概述了乳酸菌细菌素的分类、作用机制、分离纯化方法及在肉制品防腐保鲜领域的应用,并展望了以后的研究方向。     

乳酸菌细菌素的作用机制及在肉制品中的应用

乳酸菌细菌素是乳酸菌在代谢过程产生的一类具有抗菌活性的多肽或蛋白质,在各类食品中均有广泛应用。作为一种生物防腐剂,肉制品中添加乳酸菌细菌素可以抑制腐败菌和致病菌生长,从而提高产品的安全性和延长保质期。综述乳酸菌细菌素的分类、生物合成、作用机制及在肉制品中的应用,为建立乳酸菌细菌素防腐体系提供理论依据。     

乳酸菌细菌素Durancin GL对冷鲜鸡肉中单增李斯特菌抑制效果研究

以乳酸菌细菌素Durancin GL处理冷鲜鸡肉,进行储藏试验。从感官评定、品质分析以及有害微生物抑制情况考察该细菌素对冷鲜鸡肉的防腐保鲜效果。试验结果显示:200AU/mL的细菌素保鲜液处理冷鲜鸡肉,可抑制单增李斯特菌的生长,减缓挥发性盐基氮(TVB-N)含量增加以及pH上升,减缓肉质劣变;在4℃储藏条件下,一级冷鲜肉存储期由4d延长至8d。表明该乳酸菌细菌素对冷鲜鸡肉延长储藏期具有积极效果。     

产细菌素乳酸菌在食品中的应用

食品在加工贮藏过程中容易被有害微生物侵染,从而导致其腐败变质。现常用的物理化学防腐保鲜方法虽然可以延长产品的货架期但却存在一定的安全隐患,而且目前消费者更倾向于选择绿色、天然的产品,因此生物抑菌剂的开发显得尤为重要。乳酸菌是公认的食品安全级微生物,是一种天然的防腐剂,安全、无毒、开发性能稳定,被广泛应用于食品中。乳酸菌细菌素是由乳酸菌在生长代谢过程中通过核糖体合成的一类具有抗菌活性的多肽或蛋白质,对一些有害微生物的生长繁殖有明显抑制作用。本文主要介绍了乳酸菌细菌素的分类、抑菌机制及乳酸菌作为天然抑菌剂在乳及乳制品、肉及肉制品、水产品、果蔬类产品及蛋制品中的应用,以期为产抑菌素乳酸菌的综合利用与进一步的研究提供一定的理论依据。     

小龙虾即食休闲食品保鲜配方及货架期研究

为了延长小龙虾即食休闲食品的货架期，进行产品的防腐配方优化及货架期预测研究。以加工后的即食小龙虾为研究对象，根据食品添加剂的规范使用限量，对4种常用防腐剂D-异抗坏血酸钠、溶菌酶、乳酸链球菌素和山梨酸钾进行复配优化。以食品保质期加速测试(ASLT)中Q10为评价指标，将产品分别置于温度为37℃和47℃，湿度为60%的培养箱中，定期进行感官检验、菌落总数及过氧化值测定。研究结果表明，当添加D-异抗坏血酸钠0.1 g/kg、乳酸链球菌素0.4 g/kg、山梨酸钾0.8 g/kg时，防腐保鲜效果最好，冷藏4℃下货架期为80～127 d，常温20℃下货架期为42～54 d。复合保鲜剂能够有效防止微生物生长，延长小龙虾即食休闲食品的货架期。     

海洋源乳酸菌细菌素及其在海产品中的应用研究进展

海鲜在加工和储存过程中因酶、微生物和化学反应等因素极易发生腐烂变质。海洋源乳酸菌细菌素是由海洋乳酸菌核糖体合成的一种天然抗菌肽,能有效抑制多种食源性病原菌,将其用于海产品保鲜中可以减少化学防腐剂的添加以及物理处理的强度,有效延长食品的保质期。该文综述海洋源乳酸菌细菌素来源、海产品中影响乳酸菌细菌素抗菌效果的因素及其在海产品中的应用研究进展,为海产品保鲜中乳酸菌细菌素的选择和应用提供参考。     

植物乳杆菌素L-1对冷却肉的防腐保鲜效果研究

本实验研究了植物乳杆菌素L-1 对冷却肉的防腐保鲜效果。实验中对冷却肉的微生物、感官品质和理化指标三方面进行了检测。结果显示,效价320AU/ml 组效果与Nisin 相近,效价640AU/ml 组的效果优于Nisin,通过对照,效价640AU/ml 的植物乳杆菌素L-1 处理组可将冷却肉的保质期从3d 延长至12d。植物乳杆菌素L-1 对冷却肉中主要污染菌--假单胞菌和潜在致病菌--单增李斯特菌有较好的抑制效果。植物乳杆菌素L-1 作为冷却肉的生物防腐剂,具有广阔的应用前景。     

大蒜提取物对冷藏蔬菜鱼丸品质的影响

研究蔬菜鱼丸中添加不同量的大蒜提取物(0、100、150、200mg/kg)后在4℃冷藏条件下的品质变化。每5d取鱼丸样品的分析感官特性(感官评分、质构和白度)、微生物(细菌总数)和理化(pH值、TVB-N值和TBA值)等指标。结果表明：添加大蒜提取物的处理组保鲜效果明显优于对照组,其中大蒜提取物添加量在200mg/kg时,保鲜效果最佳,其货架期延长了7～8d。通过处理组与对照组细菌总数、pH值、TBA、TVB-N等品质指标的比较可知,大蒜提取物在鱼丸冷藏保鲜过程中能有效地抑制细菌生长,并减缓蛋白质、脂肪等氧化变质,从而延长了鱼丸的货架期。     

西式低温水煮火腿加工工艺及其对品质的影响

为了提高西式低温火腿品质,改善贮藏特性,降低对人体健康安全风险,以猪肉为原料,采用高阻隔尼龙肠衣灌装,低温长时水浴加热及快速冷却法制备新型低温水煮火腿,研究关键加工工艺对西式低温火腿质地特性、贮藏期微生物生长繁殖的影响。结果表明:在不添加防腐剂和包装后杀菌的条件下,采用西式低温水煮火腿加工工艺制备的火腿样品能够在0~4℃的贮存条件下达到45d的货架期。与传统的西式低温烟熏火腿相比,具有更好的质地特性和感官品质,此外该工艺还能有效降低苯并(a)芘含量。     

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