羊绒与羊毛的天然染料染色性能比较

采用4种天然染料对羊绒、羊毛进行染色,通过实验比较羊绒、羊毛染色性能的差异。选择染色温度、染液pH值、媒染剂用量和媒染时间4个因素进行正交试验。实验结果表明,羊绒的上染百分率和表观深度(K/S值)普遍高于羊毛,羊绒的天然染料染色性能优于羊毛;对上染百分率、得色率影响最大的因素是染液pH值,染液p H值稍微降低,上染百分率或得色率可明显提高;天然染料可以在低温条件下对羊绒进行染色。几种染料相比较,紫胶红可以在染色阶段达到97%以上的上染百分率(对羊绒);叶绿素铜钠盐不仅染色阶段上染百分率达95%以上、而且媒染阶段上染百分率达96%以上(对羊绒),最终达到非常高的上染百分率;栀子蓝是典型的媒染染料,染色阶段上染百分率较低,但在媒染阶段可以使上染百分率大大提高。     

羊毛、蚕丝和锦纶的活性荧光黄FL染色

采用活性荧光黄FL对羊毛、蚕丝和锦纶染色,探讨了染色方法、染色温度和时间,纯碱、氯化钠和染料质量分数对染色织物K/S值和荧光效果的影响,测试了织物染色牢度。结果表明:采用先酸后碱法染色,织物颜色较深;染色织物K/S值随纯碱质量浓度的增加先增大后减小,随氯化钠和染料质量分数的增加逐渐上升。染料质量分数为1%~4%(omf)时,染色羊毛可满足警示服的荧光要求;染料质量分数为2%~4%(omf)时,染色蚕丝织物可满足警示服的荧光要求。活性荧光黄FL质量分数为2%(omf)时,织物的最佳染色工艺条件为:染色p H值4,氯化钠30 g/L,羊毛染色时纯碱质量浓度为0.5 g/L;蚕丝和锦纶染色时纯碱质量浓度为0.25 g/L,80℃加入纯碱保温60 min,织物具有较好的耐洗和耐摩擦色牢度。     

叶绿素铜钠盐对羊毛、蚕丝和锦纶针织物染色

采用叶绿素铜钠盐对羊毛、蚕丝和锦纶针织物进行染色。探讨了染色pH值、温度、氯化钠用量、染色时间、染料用量对织物染色性能的影响,测试了染色织物的色牢度。结果表明,叶绿素铜钠盐染料适合在酸性条件下上染羊毛、蚕丝和锦纶,染色温度越高织物表观色深越深,氯化钠在酸性条件下起缓染作用;叶绿素铜钠盐对羊毛、蚕丝和锦纶直接染色的最佳工艺是染液pH值为4,升温至100℃保温60min,染色织物的耐皂洗色牢度和耐摩擦色牢度均在3级以上。     

植物靛蓝染料在蚕丝上的染色性能研究

本文研究植物靛蓝染料在蚕丝织物上的染色工艺,探讨了pH值、保险粉用量、还原时间、还原温度以及染色时间和染色温度等对蚕丝织物K/S值、强力损失率的影响,并测试了最佳工艺下蚕丝织物的色牢度。结果表明,植物靛蓝的最佳染色工艺为:保险粉用量15 g/L,NaOH调节pH值至10,还原温度40℃,还原时间15 min,染色温度60℃,染色时间40 min。在此条件下,蚕丝织物的K/S值最大,强力损失率为6.94%,耐皂洗褪色牢度、耐干摩擦色牢度、耐日晒色牢度较好,耐湿摩擦色牢度及耐皂洗沾色牢度较差。     

雅格欣红对棉和锦纶织物染色同色性的研究

采用新型染料雅格欣红对纯棉织物和锦纶织物进行染色,分析了氯化钠用量、固色时间、浴比、碳酸钠用量以及上染时间等工艺因素对棉和锦纶得色K/S值及染色同色性的影响,从而得出新型环保染料雅格欣红对棉和锦纶同浴染色的最佳工艺:染料1%(omf),氯化钠40 g/L,碳酸钠4 g/L,上染温度98℃,上染时间30 min,固色温度80℃,固色时间30 min。试验结果表明,采用该工艺对棉和锦纶织物同浴染色,可获得良好的同色性和色牢度,同色平衡值K接近1。     

活性阳离子染料的染色性能

采用活性阳离子染料对羊毛、蚕丝、尼龙、棉和腈纶织物染色,研究了p H值、染色温度、染色时间和染料质量分数对染色织物K/S值、上染率和同色性的影响,测试了染色织物的色牢度。结果表明:在活性阳离子染料2%(omf),分散剂IW 2%(omf),染色温度95℃,保温时间60 min的条件下,上染羊毛和棉织物最佳p H值为7,上染蚕丝和尼龙织物最佳p H值为8,上染腈纶织物最佳p H值为5。活性阳离子染料质量分数为1%~5%(omf)时,羊毛、尼龙和腈纶织物的同色性能优良。染色织物具有良好的耐水洗色牢度,耐摩擦色牢度和耐汗渍色牢度。     

红曲色素对羊绒织物的染色性能

研究了红曲色素应用于羊绒织物染色的可行性,探讨了染液工艺参数对染色织物K/S值和色牢度的影响。结果表明,以硫酸铝作媒染剂具有较强的配位络合作用,能与红曲色素分子和羊绒纤维形成络合结构;当硫酸铝质量浓度为3.0 g/L,pH=5,染色温度80℃,染色时间60 min,红曲色素质量浓度6.0 g/L,采用预媒染法染色得色最佳,羊绒织物的耐皂洗色牢度达到4级,耐干摩擦色牢度可达4级。     

桉木水煮液对羊毛和蚕丝上染效果的研究

桉木水煮液中含有的单宁可与羊毛和蚕丝织物中的蛋白质结合,文中采用直接染色法与同浴媒染法,将桉木水煮液作为染液对羊毛及蚕丝织物染色,探究了桉木水煮时间及金属媒染剂CuSO_4对染色性能的影响,测试了染色后织物的颜色特征值、K/S值和染色牢度。结果表明,桉木水煮液最佳水煮时间为3h;同浴媒染染色时,羊毛和蚕丝织物CuSO_4最佳用量分别为4%和2%;直接染色后羊毛、蚕丝织物具有较好的耐摩擦、耐皂洗、耐汗渍色牢度,但耐光色牢度较差;媒染染色可改变织物的色相,提高各项染色牢度,并显著提升织物的耐光色牢度。     

羊毛织物的植物染料染色

为了提高羊毛织物植物染料染色的各项色牢度,研究了羊毛织物的染色前预处理,羊毛织物玫红色、亮黄色和深蓝色3种植物染料的直接法染色和预处理后的染色工艺,分析了染色温度、染色时间和染浴pH值对羊毛织物植物染料染色效果的影响。3种植物染料对羊毛织物直接法染色的最佳染色工艺为:pH值为4.0,保温时间60 min,保温温度98℃,渗透剂用量1.5 g/L;羊毛织物经预处理后,选用亮黄色植物染料染色,影响因素大小依次为pH值温度时间,染色最佳工艺条件为pH值为4,温度98℃,保温时间50 min;选用玫红色和蓝色染料染色的影响因素大小依次均为:pH值温度时间,染色的最佳工艺条件是pH值为4,温度98℃,保温时间60 min。预处理后的羊毛织物用3种植物染料染色可获得色牢度优良的产品,其工艺简捷无污染。     

锦纶织物活性染料乙醇/水体系染色

采用乙醇/水体系活性染料对锦纶织物进行染色,研究乙醇体积百分数、初始pH、染色温度、碳酸钠质量浓度和染色时间对织物色深K/S值的影响,并与传统水浴染色效果进行比较。结果表明,乙醇/水体系中乙醇体积百分数达到90%时,染色后锦纶织物的K/S值最大。当染料质量分数为2%时,最佳染色工艺为:染浴pH为4,染色温度80℃,保温时间60 min。在80℃染色条件下,染色织物的匀染性和各项色牢度均达到了传统水浴染色效果,K/S值明显提高,不仅节约能耗、水耗,而且提高了染料利用率。     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.