姜黄素介导的光动力技术对鲜切马铃薯的杀菌效果

本文运用光动力技术（Photodynamic technology,PDT）对鲜切马铃薯进行非热杀菌,实验选用姜黄素为光敏剂,420 nm LED蓝光为激发光源。探究了光照功率、光照时间、孵育时间以及光敏剂浓度等因素对鲜切马铃薯表面大肠杆菌、金黄色葡萄球菌杀菌效果的影响,并确定最优杀菌条件。结果表明,该技术对大肠杆菌的最优杀菌条件分别为:光照功率40 W、光照时间20 min、孵育时间15 min、姜黄素浓度30 μmol/L;金黄色葡萄球菌的最佳杀菌条件分别为:光照功率40 W、光照时间10 min、孵育时间15 min、姜素浓度30 μmol/L。与对照组相比,光动力技术处理后的大肠杆菌与金黄色葡萄球菌菌落总数分别为降低3.60与5.23 lg CFU/mL。     

亚甲基蓝对单增李斯特菌菌膜的光动力杀伤作用

探讨单增李斯特菌（Listeria monocytogenes,LM）生物菌膜的生长特性及亚甲基蓝对LM生物菌膜光动力杀伤作用。通过结晶紫染色法判断与观察LM生物菌膜的形成并用酶标仪在595 nm波长处对其不同生长阶段的生物量进行测定,同时通过细菌平板菌落计数法研究亚甲基蓝对LM生物菌膜的光动力杀伤作用。结果表明：结晶紫染色法可用于定性判断与观察LM生物菌膜,且随着培养时间的延长,LM生物菌膜生物量不断增加,形成的网状结构越来越致密。当光敏剂质量浓度为10 μg/mL的亚甲基蓝在光功密度为200 mW/cm2 的可见光照射30 min时,即可使LM生物菌膜的失活率达到99.99%以上,其菌落数降低了4.08（lg（CFU/mL））。亚甲基蓝对LM生物菌膜的光动力灭活作用非常显著,其杀伤效果主要取决于光敏剂质量浓度和光照时间。     

TiO2溶胶光催化降解亚甲基蓝

以钛酸四正丁酯[Ti(OC4H9)4]为前驱体,乙醇为溶剂,盐酸为催化剂,在20℃制备了有光催化活性的TiO2溶胶.在40 W紫外灯光照条件下,通过对亚甲基蓝的降解试验,研究了溶胶制备条件、溶胶用量、光照时间和亚甲基蓝溶液初始质量浓度与光催化效果的关系.试验结果表明:当Ti(OC4H9)4与H2O量比为1:100,20℃下陈化7 d,制得的TiO2溶胶对0.20g/L亚甲基蓝溶液的降解率达到97.5%,具有较好的光催化性能.     

α-四(3-羧基苯氧基)酞菁钴的合成、表征及光催化降解亚甲基蓝

以3-硝基邻苯二甲腈为原料合成了α-四(3-羧基苯氧基)酞菁钴,利用IR、UV-Vis、LC-MS和C H N元素分析对催化剂进行了表征。在室温条件下,研究了催化剂用量和H2O2浓度对亚甲基蓝降解效果的影响。当催化剂用量为0.6 g/L、H2O2浓度为6mmol/L时,80 min后亚甲基蓝的脱色率均可达98.7%。脱色过程符合一级动力学特征,速率常数k=0.039 min-1。重复试验3次,脱色效果可达85%。     

接触辉光放电电解在阳离子染料废水中的应用

利用接触辉光放电电解（CGDE）技术降解亚甲基蓝和甲基紫染料废水，探讨了工作电压、反应液pH值、辉光放电时间和电解质Na2SO4浓度对降解效果的影响。试验表明，利用该方法可以使水中阳离子染料完全降解。亚甲基蓝和甲基紫的优化降解条件均为：工作电压700V、pH值9、辉光放电时间45min、Na2SO4用量2g／L。     

紫外LED点光源降解亚甲基蓝的动力学研究

为了研究点光源下亚甲基蓝废水的降解效率,探究了UV-LED点光源光催化的处理方法。使用UV-LED点光源探究了在不同催化条件下Ti O2对亚甲基蓝的去除效果。结果发现,在反应时间为4 h、p H为11、催化剂用量为1 g/L、溶液初始质量浓度为5 mg/L时,亚甲基蓝的去除率达到73%。UV-LED点光源催化降解亚甲基蓝的反应速率常数k符合准一级反应动力学公式,计算出k=0.064 6e-0.02ρ00.024 9p H0.335 1(0.012M3-0.06M2+0.077 4M+0.034 3)。     

麦草浆蒸煮黑液木素制备活性炭

以麦草浆蒸煮黑液中木素为原料，采用正交实验方法，探讨了活化时间、活化温度、磷料比对制备活性炭性能的影响和最佳工艺条件。结果表明，麦草浆蒸煮黑液中木素可以作为制备活性炭的优良原料，最佳制备工艺条件为：温度600％、磷料比3．5：1、活化时间70min；制备的活性炭亚甲基蓝吸附值可达16．3mL／0．1g，为活性炭国家一级品标准（LY216—79）的1．36倍。三因素对活性炭亚甲基蓝吸附能力影响顺序为：活化温度〉磷料比〉活化时间。     

亚甲基蓝分光光度法测试水中硫化物结果的影响因素探讨

为测试水中硫化物的含量,依据亚甲基蓝分光光度法显色反应原理,利用全自动水质分析仪,探讨了影响亚甲基蓝分光光度法测试水中硫化物结果的主要因素,并对配制水样进行测试与分析。试验结果表明,选用浓度为1．008g／L的N,N-二甲基对苯二胺、浓度为0．215g／L的K2Cr2O7,反应时间（t1、t2）分别为60、120S时,工作曲线线性方程为Y=0．21369＋1．45569E-4x,R2为0．997O,所测溶液A值范围在最佳测试范围内;该试验表明,利用该方法测试水样中硫化物含量时,结果准确,精度较高。     

磷酸活化文冠果果壳生物炭及其对亚甲基蓝的吸附性能

目的：探究文冠果相关产业废弃物处置方法。方法：以文冠果果壳为原料,磷酸为活化剂,在单因素试验基础上,采用Box-Behnken中心组合设计进行生物炭制备条件优化,并将最优制备条件下所得生物炭用于吸附水体中亚甲基蓝,通过考察吸附影响因素,确定磷酸活化制备的文冠果果壳生物炭对亚甲基蓝的吸附特性,并结合动力学分析探讨其吸附机理。结果：磷酸活化制备文冠果果壳生物炭的最优工艺条件为浸渍比（m_果壳粉∶m_磷酸溶液）1∶21,热解温度530 ℃,热解时间75 min。文冠果果壳生物炭吸附水体中亚甲基蓝最优条件为溶液初始pH 12.6,生物炭投加量1.0 g/L,亚甲基蓝初始质量浓度200 mg/L,吸附平衡时间120 min。文冠果果壳生物炭对水体中的亚甲基蓝吸附服从准二级反应动力学关系,吸附过程由液膜扩散控制、孔隙扩散控制和吸附解析平衡3个阶段组成。结论：磷酸活化可显著提升文冠果果壳生物炭比表面积和孔容,进而显著提升其对亚甲基蓝的吸附性能。     

罗非鱼鱼鳞对染料废水中亚甲基蓝的吸附研究北大核心

通过吸附实验,考察鱼鳞用量、亚甲基蓝初始质量浓度和溶液pH等因素对罗非鱼鱼鳞吸附水中亚甲基蓝性能的影响,通过红外光谱、BET、SEM、吸附动力学和吸附等温线分析吸附机理。结果表明:当溶液pH为7、温度为30℃,吸附剂用量为3 g/L、吸附时间为30 min,亚甲基蓝初始质量浓度为40 mg/L时,吸附效果最好;罗非鱼鱼鳞对亚甲基蓝的吸附过程符合Lagergren准二级动力学模型,吸附过程属于物理吸附;吸附等温线符合Langmuir吸附等温式;傅里叶红外光谱分析表明罗非鱼鱼鳞中的胶原蛋白和羟基鳞灰石均参与了亚甲基蓝染料的吸附。     

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