羊毛针织物蛋白酶防毡缩整理的工艺研究

由于羊毛纤维表面结构的特殊性 ,导致了羊毛纤维具有毡缩倾向。为此对羊毛织物进行蛋白酶防毡缩整理。文中对碱性蛋白酶MaxacalL、Novozyme 680T和HAP在羊毛针织物的整理进行了研究 ,并探讨了蛋白酶浓度、pH值、温度和时间对整理效果的影响。结果表明 ,MaxacalL蛋白酶处理后的织物防毡缩效果最好     

羊毛针织物蛋白酶防缩整理的工艺研究

由于羊毛纤维表面结构的特殊性，导致了羊毛纤维具有毡缩倾向。为此对羊毛织物进行蛋白酶防缩整理。文中对碱性蛋白酶Maxacal L、Novozyme 680T和HAP在羊毛针织物的整理进行了研究，并探讨了蛋白酶浓度、pH值、温度和时间对整理效果的影响。结果表明，Maxacal L蛋白酶处理后的织物防毡缩效果最好。     

TG酶在修复羊毛损伤中的应用

为了减少羊毛蛋白酶防毡缩造成的损伤,应用TG酶对羊毛织物进行整理,研究TG酶对羊毛损伤的修复作用。结果表明：TG 酶可以修复化学预处理和蛋白酶防毡缩处理对羊毛造成的损伤,使羊毛织物强力增加,碱溶度下降。TG酶可以催化羊毛纤维蛋白质分子内的交联。羊毛的蛋白酶/TG酶联合防毡缩的最佳工艺为: 蛋白酶Sav用量1%（o.w.f.）, 蛋白酶Sav作用时间30min,pH值8~9;TG酶用量2%（o.w.f.）,TG酶作用时间50min,pH值6~7;浴比均为20:1,温度均为50℃,该工艺处理后羊毛织物的毡缩率为2.93%, 强力380.4N,强力损伤控制在7.4%。     

前处理对毛织物防毡缩整理的影响

为了改善羊毛织物毡缩性能,运用不同前处理与蛋白酶结合的方法对羊毛织物进行表面改性,探讨整理后织物毡缩性能和强力的变化,从而确定最佳前处理方案。应用SEM研究不同前处理、前处理与蛋白酶共同整理对织物表面形貌的影响,探讨不同前处理对羊毛用蛋白酶处理防毡缩性能的影响。研究结果表明:仅用蛋白酶处理,羊毛织物毡缩率仅下降到11.4%,很难达到羊毛防毡缩的目的,LTP前处理对于其后进行的蛋白酶防毡缩处理效果具有显著的影响,毡缩率下降到5.6%,达到了国际羊毛局防毡缩标准。     

Savinase蛋白酶用于毛织物防毡缩整理的工艺探讨

选用Savinase蛋白酶对羊毛织物进行防毡缩处理,采用非氯氧化剂——双氧水作为前处理剂,通过Savinase蛋白酶酶活测试,确定初步的实验参数,采用单因素分析和正交试验相结合的方法,确定Savinase蛋白酶防毡缩整理的最佳工艺为:蛋白酶用量3%(owf)、p H值7、温度55℃,时间40 min、浴比1∶30。实验结果表明,Savinase酶对羊毛织物防缩整理可使羊毛缩率下降到5.60%,由此得出,Savinase蛋白酶整理可使羊毛织物获得较好的防缩效果。     

固定化中性蛋白酶在羊毛针织物防毡缩处理中的应用

研究了用固定化中性蛋白酶进行羊毛针织物防毡缩处理工艺,进行了单因素分析实验,通过正交试验确定了固定化中性蛋白酶处理工艺参数。结果表明:固定化中性蛋白酶用量5%(owf),温度50℃,pH值7.0,处理时间60 min时处理效果较好。比较了游离蛋白酶与固定化蛋白酶用于羊毛针织物的防毡缩整理试验,固定化蛋白酶处理羊毛针织物防毡缩效果提高37.6%,失重率降低45.2%,强力损伤降低52.7%,白度提高23.2%,起毛起球提高了2级,这将为羊毛针织物防毡缩整理用酶奠定基础。     

羊毛针织物蛋白酶防毡缩整理的研究

文章对碱性蛋白酶在羊毛针织物的防毡缩整理上的应用进行了研究.通过正交试验得到最佳工艺条件为:双氧水体积分数40 mL/L、温度45℃、时间45 min、pH值8,蛋白酶3%(owf)、温度45℃、时间35 min、pH值8.经此工艺条件处理的羊毛针织物,防毡缩性和悬垂性都有提高.     

等离子体/蛋白酶联合整理对羊毛防缩性能的影响

为改善羊毛织物毡缩性能,运用低温等离子体与蛋白酶结合的方法对羊毛织物进行表面改性,探讨整理后织物毡缩性能和强力的变化.应用SEM观察等离子体/蛋白酶处理对织物表面形貌的影响,应用红外光谱表征改性后织物表面分子结构的变化.结果表明:处理后,织物的表面形态发生了变化,羊毛织物毡缩率不仅下降到5.4％,而且能基本保留羊毛织物原有的强力.由此得出,低温等离子体与蛋白酶联合整理可使羊毛织物获得良好的防毡缩效果.     

蛋白酶和有机硅改性聚氨酯联合防毡缩工艺

为了改善水性聚氨酯对羊毛织物防毡缩处理时用量过大而造成织物发硬、手感差和单独蛋白酶防毡缩整理时强力损伤严重的问题,文章将羊毛织物用蛋白酶Esperase 8.0L预处理后再经有机硅改性水性聚氨酯(WSPU)联合防毡缩整理。探讨了蛋白酶Esperase 8.0L最佳酶活,确定了有机硅改性水性聚氨酯的最佳配比。以羊毛织物的面积毡缩率、强力为评价指标,优化出联合防毡缩整理工艺。该工艺整理后的羊毛织物满足国际羊毛局防毡缩技术标准和市场对机可洗产品的质量要求,整理后织物的柔软性和手感得到改善。采用衰减全反射傅里叶变换红外光谱、扫描电子显微镜和织物风格测试对整理前后织物的变化进行了分析和探讨。     

羊毛织物酶法与化学法防毡缩整理效果比较

针对现有研究中采用蛋白酶种类、酶活不同以及羊毛织物规格不一致等原因,难以对不同工艺处理后的织物进行直接地防毡缩整理效果比较,故基于羊毛“减法”防毡缩原理,考察了相同规格羊毛织物的酶法(角蛋白酶、蛋白酶、角蛋白酶-蛋白酶复合和DCCA-蛋白酶复合)与化学法(二氯异氰尿酸DCCA、过氧甲酸和KMnO4)防毡缩整理效果。结果表明:羊毛织物经蛋白酶单独处理时的防毡缩效果较好,润湿性明显提高;蛋白酶分别与DCCA和角蛋白酶复合处理羊毛织物时,纤维鳞片层被进一步破坏,织物的防毡缩效果更好。     

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