壳聚糖季铵盐(HTCC)改性桑蚕丝织物的活性染料无盐染色

壳聚糖季铵盐(HTCC)是一种具有强阳离子性的水溶性聚合物,采用HTCC对桑蚕丝织物进行改性处理,研究改性后丝织物对活性染料的无盐染色工艺及性能.结果表明,经HTCC溶液改性后,桑蚕丝织物对活性染料的无盐染色较佳工艺为:染液pH为8.0,染色温度为90℃,染色时间为70 min.改性后的丝织物经无盐染色后,上染率、固色率及色深明显提高,水洗色牢度和摩擦色牢度也略有改善.     

壳聚糖衍生物对大豆蛋白复合纤维性能的影响

以2,3-环氧丙基三甲基氯化铵和N-羟甲基丙烯酰胺为改性剂,对壳聚糖进行改性,得到壳聚糖衍生物(NMA-HTCC),并对NMA-HTCC进行红外光谱和热分析测试。利用NMA-HTCC对大豆蛋白复合纤维针织物改性,然后进行无盐染色,并测试抗菌性能。结果表明,壳聚糖改性后热稳定性有所下降;NMA-HTCC改性的大豆蛋白复合纤维针织物,在染色中可以实现无盐染色,织物的耐水洗色牢度与传统工艺相当,而且染色残液的COD值明显降低;NMA-HTCC还可提高大豆蛋白复合纤维对金黄色葡萄球菌和大肠杆菌的抑菌效果。     

竹原纤维阳离子改性及其活性无盐染色研究

以一氯均三嗪与环氧丙基为反应性基团制备多活性季铵化合物棉用改性剂,并用于竹原纤维织物的改性;将改性后的纤维采用活性染料染色,并与传统活性染料染色和未改性无盐染色工艺进行比较。试验结果表明,改性后竹原纤维织物得色量和固色率有一定提高,染料上染率与常规染色相近。但用红色染料染色时,改性无盐工艺与常规工艺染色织物色光不一致;金黄色与藏青色染色时,色光一致。     

壳聚糖季铵盐改性亚麻织物的工艺优化

合成了低分子质量壳聚糖季铵盐HTCC,并用来改性亚麻织物,通过中心复合设计试验和响应面分析研究壳聚糖季铵盐用量、浸渍温度、浸渍时间和焙烘温度对改性亚麻织物活性染料染色的影响。2次方模型的方差分析数据表明,亚麻织物染色效果的影响程度排序:HTCC用量浸渍温度浸渍时间焙烘温度。壳聚糖季铵盐改性亚麻织物活性染料染色体系要获得较好的上染率可以通过增加HTCC用量、升高浸渍温度、延长浸渍时间来实现。响应面分析得出较佳的改性工艺为:HTCC用量8 g/L,浸渍温度65℃,浸渍时间80 min,焙烘温度110℃。     

壳聚糖季铵盐改性棉织物的无盐染色工艺研究

利用壳聚糖和2,3-环氧丙基三甲基氯化铵制备壳聚糖季铵盐对棉针织物进行改性,分析壳聚糖季铵盐的结构特征,探讨壳聚糖季铵盐改性棉针织物预处理工艺中改性剂壳聚糖季铵盐的用量、浸渍时间和浸渍温度对染料上染百分率和K/S值的影响。结果表明,壳聚糖季铵盐改性棉针织物的最佳工艺为:壳聚糖季铵盐浓度8 g/L、浸渍时间60 min、浸渍温度70℃、浴比1∶30;经壳聚糖季铵盐改性后棉织物能够实现活性染料的无盐染色,织物具有较好的耐洗、耐摩擦色牢度,满足服用需求。     

多活性基阳离子交联剂改性棉的无盐染色

以一氯均三嗪和环氧丙基为反应性基团的多活性季铵化合物，用于棉纤维的改性；改性后的纤维采用活性染料染色。研究了改性时间、浓度等条件对染色性能的影响。结果表明，与传统活性染料染色工艺相比，改性织物采用无盐染色工艺，在无电解质存在的条件下，上染率和固色率均有大幅度提高，湿处理牢度优于常规染色。     

HTCC对真丝织物抗菌、抗皱和染色性能的影响

采用HTCC(壳聚糖季铵盐)溶液对桑蚕丝织物进行处理,并对处理前后桑蚕丝织物的抗菌、抗皱和染色性能进行探讨。结果表明,壳聚糖合成HTCC后水溶性提高,结晶度和热稳定性下降;经HTCC溶液处理后,真丝织物对大肠杆菌和金黄色葡萄球菌的抑菌率提高,抗皱和染色性能得到改善,而对白度影响不大。     

活性染料固色剂壳聚糖季铵盐的制备和性能

以3-氯-2-羟丙基三甲基氯化铵(CTA)为改性剂,利用超声波的空化作用对壳聚糖进行季铵化改性,合成了羟丙基三甲基氯化铵壳聚糖(HTCC)。制备的优化工艺为:以异丙醇为溶剂,CTA与壳聚糖摩尔分数比1∶6,温度70℃,超声波功率100W,作用时间3h,制得的壳聚糖季铵盐取代度为0.84。将得到的产物用作活性染料固色剂,可将染色织物的摩擦牢度、皂洗牢度和日晒牢度提高0.5～1级。     

氧化降解壳聚糖在大豆纤维染色中的应用

利用双氧水氧化降解壳聚糖(CTS),采用粘度稀释法测定降解前后壳聚糖的分子量。将降解后不同分子量的壳聚糖溶解于1%醋酸溶液中处理大豆纤维织物,进行正交实验,研究对大豆纤维染色的增深效果。结果表明,降解后的分子量为11.7万壳聚糖在温度80℃,浓度4g/L,时间20min处理大豆纤维织物达到的增深效果最好;降解后的分子量为2.42万壳聚糖在温度80℃,浓度1g/L,时间20min处理大豆纤维织物达到的增深效果最好。将CTS应用于大豆纤维织物的表面改性,在不降低染色牢度的情况下可以改善活性染料的染色效果。     

改性壳聚糖对合纤织物整理的结合状态分析

为探讨壳聚糖对抗菌整理合纤织物的结合状态,采取3种工艺配方将改性的季铵盐壳聚糖(HTCC)配制成改性壳聚糖抗菌整理液。以腈纶针织面料和维纶包装袋为试样,用改性壳聚糖抗菌整理液对织物进行后整理。通过扫描电镜观察和傅里叶红外光谱分析,探究改性壳聚糖在纤维上的吸附结合状况。研究结果表明:在黏合剂体系作用下,改性后的季铵盐壳聚糖与腈纶及维纶织物都发生了黏附结合,织物表面确实有改性壳聚糖的吸附存在,从而达到了对合纤织物抗菌整理的目的。     

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.     

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.     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.