铬-铁-植结合鞣革的色泽与性能研究(续)

用自制有机铬-铁配合物鞣剂(Cr∶Fe=1·7∶1,鞣剂用量折合总氧化物为1·5%)对浸酸猪皮进行鞣制,再分别用荆树皮、落叶松、坚木、栗木等10种栲胶进行复鞣(栲胶用量为5%或8%),考察鞣制坯革的颜色及其坚牢度、收缩温度、物理机械性能及耐各种老化性能,探讨铬-铁-植结合鞣与染色一体化的可能性。试验结果表明:用铬-铁-植结合鞣制皮革,一般呈黑色、黑灰色、棕黑色,颜色均匀、渗透、干湿擦坚牢度良好,收缩温度、物理-机械性能可以满足产品要求,用该方法生产黑色革可节约染料或省去染色工序,在实现少铬鞣制的同时减少或避免用合成染料,属于一种环保型鞣制方法。综合考虑皮革的收缩温度、物理-机械性能、耐老化性,栗木、坚木、橡、漆叶栲胶与铬-铁结合鞣的效果较好;为了确保皮革的耐老化性能,铬盐用量不宜太少。     

黑色革植-铬-铁结合鞣与染色一体化研究

基于植物丹宁与铁盐反应显色的原理,研究用栗木栲胶与铬-铁鞣剂结合鞣制,以实现黑色革鞣制与染色一体化,减少或免去用合成染料染色和铬盐用量。研究表明:当栲胶用量为5%,铬-铁鞣剂用量折合Cr_2O_3为1.5%～1.8%,Fe_2O_3为0.7%,鞣制的革呈纯黑色,收缩温度可达到100℃以上,手感丰满柔软,粒面细致,色牢度优良。     

F-90与植物鞣剂结合鞣制工艺技术研究

为改善F-90鞣革性能,采用先以F-90进行预鞣,后以栗木栲胶KPS、荆树皮栲胶FS、坚木栲胶ATO等植物鞣剂进行主鞣的结合鞣制工艺。设计了四因素三水平正交试验(L9(34)),以植鞣革的收缩温度、增厚率、物理机械性能、感官性能及废液COD为评价指标。试验结果表明:采用9%F-90预鞣,采用8%KPS、4%FS和8%ATO在100%的液比条件下进行主鞣,所得植鞣革收缩温度为82.9℃,增厚率为50.12%,规定负荷伸长率为28. 68%,崩裂高度为9.4 mm,撕裂强度为100.49 N/mm,抗张强度为21.76 N/mm~2,感官性能良好,满足鞋面用皮革标准。由于鞣制废液不含铬,环境效益显著。     

板栗刺壳栲胶在山羊酸皮主鞣工艺中的应用研究

通过提取板栗刺壳中的栲胶对山羊酸皮进行主鞣。研究栲胶用量、初始p H、结束p H、鞣制时间对植鞣后的酸皮性能的影响,采用正交实验对酸皮鞣制工艺进行优化,得到山羊酸皮用作内底革和汽车装饰用皮革的最佳工艺条件。将改性后的板栗刺壳栲胶对山羊酸皮进行鞣制,并与市场上已有的栗木栲胶、坚木栲胶鞣制的皮革进行性能比较。结果表明,山羊酸皮用作内底革时的最佳工艺条件为栲胶用量14%,初始p H 4.0,结束p H4.5,植鞣时间4 h。山羊酸皮用作汽车装饰用皮革时的最佳工艺条件为栲胶用量11%,初始p H 4.0,结束p H 4.0,植鞣时间6 h。用板栗刺壳栲胶鞣制的山羊酸皮与用坚木栲胶、栗木栲胶鞣制的山羊酸皮相比,其抗张强度、收缩温度较高,伸长率大致相同,但用板栗刺壳栲胶鞣制的山羊酸皮粒面情况和柔软度较差,故当山羊酸皮用作某种对粒面情况、柔软度要求较低的皮革时,板栗刺壳栲胶可以代替市场上已有的栲胶。     

铁-锆-铝配合鞣剂及其在山羊鞋面革鞣制中的应用

通过对自制系列铁-锆-铝配合鞣剂的稳定性、反应性进行检测,优选出最佳的铁-锆-铝配合鞣剂配比,并基于铁-锆-铝配合鞣剂及其鞣革体系进行山羊鞋面革的制作,检测所鞣得坯革的物理机械性能、化学性能、感官性能和耐水性等,并与传统铬鞣革进行对比。研究发现:所鞣得坯革的收缩温度达到了88.7℃,成革平均收缩温度达到90℃以上,同时所鞣革的物理机械性能、感官性能均达到了行业标准对鞋面革的要求,与铬鞣革接近。与纯铁鞣相比,铁-锆-铝配合鞣剂所鞣革具有优良的耐水洗能力。业已证实,采用本研究的铁-锆-铝配合鞣剂及其配套工艺鞣制的山羊鞋面革,其鞣制效果可与铬鞣革媲美。     

基于植物鞣剂的黄牛白湿革无铬复鞣技术研究

以新型绿色无铬鞣剂锆-铝-钛鞣制后的黄牛白湿革为原材料,采用ATO(坚木栲胶),FS(荆树皮栲胶),ME(改性荆树皮栲胶)和KPS(改性栗木栲胶)等四种植物鞣剂设计两步法正交复鞣试验,并以复鞣后坯革的收缩温度、增厚率、物理机械性能和感官性能为评价指标进行了工艺优化。试验结果表明,最优工艺为先用ATO 10%和FS 3%,再用ME 7%和KPS 5%,最后用锆-铝-钛鞣剂2%,复鞣后所得坯革的增厚率为50.5%,收缩温度为(92.8±0.3)℃,力学性能和感官性能均符合行业标准要求。     

铬-铝-锆-植鞣猪底革的研究

多种鞣剂制造底革的研究工作,国内外很多制革工作者作出了不少贡献。早在五十年代,西德石他特博士提出铬-植鞣制法,苏联契尔诺夫曾研究过铬-铝-植鞣制,还有采用代替性合成鞣剂代替天然栲胶鞣制的。我国北京、天津、上海皮革研究所和工厂先后对铝-植、铬-植、锆-植和醛-植等鞣制和鞣革机理进行了广泛的研究。其研究的目的是发挥各种鞣剂的鞣革特点,相辅相成,使成革达到坚实有弹性、延伸率小、不易变形、抗     

铬-铁异核配合物鞣剂鞣革的性能研究

以纯铬鞣和纯铁鞣坯革为参照,采用多功能材料试验机、DSC差示扫描量热仪、皮革柔软度测定仪等系统研究了有机铬铁异核配合物鞣剂鞣制坯革的物理-力学性能、热稳定性和耐热空气老化、耐湿热老化和耐热氧老化性能.结果表明采用有机铬-铁异核配合物鞣剂鞣制的坯革物理力学性能和透气性优良,革纤维发生热收缩的温度较铬鞣革低4℃左右,明显高于铁鞣革,在一定程度上克服了铁鞣革不耐老化的缺陷.     

基于植物鞣剂的无金属鞣黄牛鞋面革生产工艺探讨

研究采用醛鞣剂和合成鞣剂搭配3种植物栲胶对黄牛皮进行预鞣与主鞣处理,探索了基于植物鞣剂的无金属鞣黄牛鞋面革的生产工艺,分析测试了所鞣坯革的收缩温度、增厚率、感观及物理力学性能。研究表明:采用2%的醛鞣剂GT50、4%的合成鞣剂AS、2%的合成鞣剂DLE预鞣,再以8%的坚木栲胶ATO、8%的荆树栲胶ME和10%的栗木栲胶KPS对其进行主鞣,通过上述方法所得坯革的综合性能最优,为以植鞣为主的牛皮轻革生产提供了一定的理论与试验依据。     

植-无铬鞣剂TWT结合鞣法研究

研究了无铬鞣剂TWT与植物鞣剂的结合鞣法。结果表明,TWT鞣剂与荆树皮栲胶和杨梅栲胶进行结合鞣制,成革收缩温度较高。较佳的鞣制条件为:首先用20%的荆树皮栲胶或杨梅栲胶进行鞣制,然后在pH4.0~6.0和50℃的条件下,用6%的TWT结合鞣3 h,成革的收缩温度可达到94℃。本研究进一步对植-改性戊二醛、植-噁唑烷和植-TWT三种结合鞣法进行了比较,结果表明植-TWT结合鞣制皮坯对加脂剂的吸收率最高,成革中游离甲醛含量最低。因此,植-TWT结合鞣法具有突出的环保性能。     

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