载Nisin壳聚糖淀粉涂布纸的制备与性能分析

制备一种以天然生物材料为防油抗菌涂层的新型防油抗菌纸,并测试其防油抗菌性能。将防油抗菌剂涂布于纸张表面制备防油抗菌纸,用表面排斥法测试其防油等级,用菌落法计算纸张对大肠杆菌与金黄色葡萄球菌的抑制率。结果表明:1g/100mL壳聚糖溶液与10g/100mL淀粉溶液体积比为12时,涂布纸张的防油等级达到8,防油部分成本约为0.3元/m2;Nisin的添加量达到1g/100mL时,涂布纸张对大肠杆菌以及金黄色葡萄球菌的抑制率分别为70.3%,72.8%。载Nisin壳聚糖淀粉涂布纸在保证防油性的同时,较壳聚糖涂布纸有效降低了成本,控制了黏度,且具有比淀粉涂布纸张更好的韧性与平整度,能有效抑制大肠杆菌和金黄色葡萄球菌。     

壳聚糖-蒙脱土复合抗菌涂布纸的制备及性能研究

制备了壳聚糖(CS)-蒙脱土(MMT)复合涂布液,进而对纸张进行涂布,制得CS-MMT抗菌涂布纸。研究了复合涂布液制备工艺对涂布纸抗张指数以及对金黄色葡萄球菌抑菌性能的影响。结果表明,CS用量为2%、CS与MMT用量比为3∶1,CS相对分子质量为20万～50万时,抗菌涂布纸对金黄色葡萄球菌有很好的抑菌性,同时纸张的抗张指数也得到明显改善。对涂布液的红外光谱和X射线谱图分析表明,CS已进入到MMT的层间。抗菌涂布纸SEM分析表明,CS-MMT复合涂布液在纸张表面形成了膜层。     

载银壳聚糖涂布液的制备及涂布纸抑菌性能的研究

以壳聚糖(CS)和AgNO3为原料,以Na BH4为还原剂,制备了载银壳聚糖(Ag-CS)涂布液,进而对纸张涂布,制得涂布纸。利用FT-IR、XRD和SEM分析其结构和形貌,研究了制备工艺对涂布纸抗张指数以及对金黄色葡萄球菌的抑菌性能的影响。结果表明,CS中的-NH2和-OH与Ag+发生配位结合,并使得结晶度下降。CS用量为1%,AgNO3用量为0.2mmol/l,Na BH4用量为0.3mmol/l,CS相对分子质量为500k Da时,涂布纸对金黄色葡萄球菌有很好的抑菌性,同时纸页的抗张指数也得到改善。涂布纸SEM分析表明,载银壳聚糖涂布液在纸页表面形成膜层。     

壳聚糖应用于纸张阻隔性涂布的研究

使用壳聚糖溶液对纸张进行涂布,研究了不同涂布量下纸张表面孔隙的封闭程度及涂布纸的阻氧性能与阻湿性能,探讨了壳聚糖/PVDC(聚偏二氯乙烯)复合涂布对涂布纸阻湿性能的改善情况.结果表明,涂布0.46g/m2壳聚糖能够将纸张表面原有孔隙填满,进一步增大壳聚糖涂布量,纸张表面完全被壳聚糖膜层覆盖,平整程度提高.壳聚糖涂布能够显著提高纸张的阻氧性能,当壳聚糖单层涂布量为1.96 g/m2时,涂布纸的氧气透过率相对原纸至少下降了99.3％,但水蒸气透过率相对原纸有所上升.使用壳聚糖/PVDC复合涂布时,在1.96g/m2壳聚糖涂层基础上二次涂布7 40 g/m2 PVDC,水蒸气透过率相对单独涂布壳聚糖下降了66.3％,降至原纸的44.8％,与此同时.阻氧性能及表面抗水性均有较大提升.     

改性纤维素纳米纤丝涂布制备高阻隔长纤维薄页纸的研究

本研究以高透气、高强度的长纤维薄页纸为基材,利用纤维素纳米纤丝（CNF）和烷基烯酮二聚物（AKD）乳液涂布制备一种高强度、高透光、柔软的高阻隔长纤维薄页纸。比较了CNF、羧甲基化改性纤维素纳米纤丝（C-CNF）、AKD等对涂布后纸张的抗张强度、透气度、水蒸气透过率、表面疏水性能等的影响。结果表明,C-CNF较CNF表现出更优异的性能,当涂布液浓度为1.0%（涂布量1.6 g/m²）时,纸张抗张指数为27.3 N·m/g,较只涂布AKD提高了46.0%;水与纸面接触角达到121.5°,较CNF涂布的疏水效果进一步提高,相比只涂布AKD的纸张增大了60.9%;同时透气度则仅有21.1 μm/(Pa·s),较CNF涂布纸的透气度进一步降低,相较只涂布AKD的纸张降低了60%;水蒸气透过率为1.95×10^-11 g·m/（m²·s·Pa）,为只涂布AKD的纸张的52%,具有良好的疏水阻隔性能。     

不同种类淀粉对纸质文献加固保护的研究

本研究选用造纸工业中常用的玉米淀粉、木薯淀粉及小麦淀粉用于纸质文献加固,对比了不同淀粉的加固效果和耐老化性能。结果表明,相比玉米淀粉和木薯淀粉,小麦淀粉更适合用于纸质文献加固保护,在淀粉吸收量约为5.0 g/m²时,加固处理后纸张的抗张指数提升14.7%,撕裂指数提升29.0%,湿热老化3天后,纸张抗张指数下降1.9%,撕裂指数下降6.3%,色差变化为1.48,对纸张外观无明显影响。     

N-琥珀酰化壳聚糖钠的制备及其在卷烟纸表面施胶中的应用

以丁二酸酐为酰化剂,制备了N-琥珀酰化壳聚糖,并研究了将其钠盐(N-琥珀酰化壳聚糖钠)溶液与淀粉复配作为卷烟纸表面施胶剂对卷烟纸表面强度和抗菌性的影响。研究表明,当N-琥珀酰化壳聚糖钠/淀粉表面施胶剂用量为0.6%时,纸张抗张指数、耐破指数、撕裂指数和耐折度分别提高26.1%、79.0%、48.6%和18.8%;N-琥珀酰化壳聚糖钠与淀粉的质量比介于5∶2～1∶3时,抑菌效率可达93.3%～98.1%。     

环保防油剂对防油纸性能的影响

不同于覆膜防油纸和含氟防油纸,本研究通过调整环保防油剂的种类、涂布量,制备可降解、不含氟的环保防油纸。结果表明,环保丙烯酸类防油剂的涂布量对纸张的防油等级起决定性作用,防油等级随着涂布量的增加而增大。3种丙烯酸类防油剂都具有一定的防油效果,涂布后纸张的防油等级达到12级。综合考虑涂布量和成本等因素,丙2防油剂效果最优,其涂布量为5.5 g/m²时,涂布纸的抗张指数92.4 N·m/g,Cobb值10 g/m²,透气率0.034 mm/s。     

载银壳聚糖涂布液的制备及其涂布纸保鲜性能的研究

以壳聚糖(CS)和AgNO3为原料,以NaBH4为还原剂,制备载银壳聚糖(Ag-CS)涂布液;然后对纸张涂布,制得涂布纸.利用FT-IR、XRD和SEM分析其结构和形貌;利用涂布纸对圣女果进行包装,测定6天后圣女果的失重率、可滴定酸和抗坏血酸(Vc)含量,考察涂布液制备条件对涂布纸保鲜性能的影响.结果表明:CS中的-NH2和-OH与Ag+发生配位结合,使得结晶度下降;涂布纸SEM的分析表明载银壳聚糖涂布液在纸页表面形成膜层;在CS用量1.5％、AgNO3用量0.2 mmol·L-1、NaBH4用量0.3 mmol·L-1、CS相对分子质量500 kDa时,可获得最佳的保鲜性能;Ag-CS涂布纸有利于减少营养物质的流失,从而延长果蔬的常温贮藏期.     

超疏水抗菌包装纸的制备及其性能研究

以竹浆为原料,结合浆内添加山梨酸钾和表面涂布蜂蜡-纳米TiO2复合物的方法制备了具有自清洁功能的超疏水抗菌纸。利用扫描电子显微镜（SEM）、原子力显微镜（AFM）、X射线光电子能谱（XPS）仪、傅里叶变换红外光谱（FT-IR）仪、抗张/耐折度仪和接触角测定仪对纸张的表面形貌、元素组成、化学结构、力学性能及疏水性能进行了表征。结果表明,所制备的超疏水抗菌纸的抗张指数为89.7 N·m/g,加热处理后其水接触角（WCA）可达152.6°,被酸/碱液浸泡12 h后,其WCA仍能稳定保持在140°以上,具有优异的自清洁特性。抗菌测试结果表明,制得的超疏水抗菌纸对大肠杆菌和金黄色葡萄球菌的抑菌率均达到约100%,说明该超疏水抗菌纸在食品包装用纸领域具有较大的应用潜力。     

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