超声波辅助醇提法提取栀子中栀子黄色素

提高栀子果中栀子黄色素的提取率对后期栀子黄色素的精制及应用具有积极促进作用。该研究旨在建立一种从栀子果实中提取栀子黄色素的有效经济方法。通过超声辅助法研究栀子果实中粒度、提取时间、提取温度、提取剂浓度及液料比对栀子黄色素提取率的影响，基于单因素实验结果，采用五因素三水平的响应面法优化提取工艺，以提高栀子黄色素的提取率。结果显示，栀子黄色素的最佳提取工艺是提取时间31 min、提取温度62℃、液料比25∶1、乙醇浓度48%、粒度80目。采用响应面法优化后的提取工艺，栀子黄色素实际平均提取率为18.36%,与响应预测值18.38%相差0.02%,误差为0.19%,误差较小，说明该工艺具有良好的可靠性。与单因素实验相比，优化后的提取工艺将栀子黄色素的提取率从15.15%提高到18.36%,故优化后的工艺有利于栀子黄色素的提取，具有实际应用价值。     

栀子黄色素水提工艺的研究

对栀子黄色素的相关提取因素进行了系统的研究,试验结果表明,栀子黄色素的最大吸收波长为440nm,采用水作为提取剂,4000r/min离心20min,离心温度4℃,采用正交试验确定浸提法的最佳工艺条件为提取料液比为1∶5,提取温度为60℃,浸提时间为30min.     

栀子黄色素的提取与精制工艺研究进展

栀子黄色素是从栀子中提取的优良天然黄色素,具有一定的营养和保健价值,在食品加工业和饮料制造业中被广泛应用。对栀子黄色素的提取、分离方法和精制工艺等进行了简要综述,以期为栀子黄色素的开发提供一定的理论基础和依据。     

栀子黄色素微波提取工艺

对栀子黄色素微波提取工艺进行了研究。通过正交实验优化工艺条件,确定了栀子黄色素微波提取的工艺为提取液乙醇浓度50%、微波功率400W、提取时间90s、料液比1∶10、提取次数1次,色素提取率达94.14%。     

一次性分离纯化栀子黄和栀子苷的工艺研究

目前我国所生产的栀子黄色素杂质含量高,不能达到出口标准。采用4因素3水平对低浓度60%乙醇提取栀子黄色素进行正交设计,以得出低浓度乙醇提取栀子黄的最佳工艺,进而利用HPD100A大孔树脂对栀子黄初液进行一次性分离纯化并对其工艺进行优化,最终得到低OD值比率(≤0.29)的栀子黄色素与高纯度(≥90%)的栀子苷。结果表明,该方法是一种切实可行、成本低、简便高效的工艺方法。     

栀子渣中植物蛋白提取工艺的研究

本实验以栀子渣为原料,采用"碱溶酸沉"原理,通过对料液比、浸提温度、浸提时间及浸提液pH值进行单因素试验,采用L9(34)正交试验对栀子渣中植物蛋白提取工艺条件进行优选。结果表明:浸提液的pH值对植物蛋白提取率的影响程度达到极显著水平,料液比、浸提温度及浸提时间对植物蛋白提取率没有显著影响。栀子渣中植物蛋白提取的最佳工艺条件为:浸提液pH值为9.0、料液比1:20、浸提时间1.5h、浸提温度40℃。     

超声波提取-分光光度法测定枸杞中黄色素的研究

以干燥枸杞为原料,采用超声波浸提一分光光度法测定枸杞中黄色素,对黄色素的提取工艺进行了比较研究,通过正交试验,系统地讨论了浸提荆的选择、浸提荆体积、浸提温度、浸提时间、浸提荆浓度对超声提取枸杞中黄色素的影响。确定了最佳提取工艺条件为：体积为70％的30mL丙酮水溶液作为浸提荆,加入0.3g样品,控制温度为50℃,进行1.5h超声提取,浸提结果较为满意。超声波提取枸杞黄色素与传统浸提法相比,具有节省时间、节省溶剂、节省资源、操作简单方便等优点。     

蒲公英黄色素提取工艺优化

以提取液吸光值为提取效果,通过分光光度计分析,确定70%乙醇为最佳浸提剂,提取液最大吸收波长λmax为440 nm。对蒲公英黄色素的提取进行了初步探索,优化蒲公英黄色素提取工艺,旨在开发新的天然色素资源,为工业化提取和精制蒲公英黄色素提供理论基础。通过超声处理,有机溶剂浸提法,选择无毒、无残留的乙醇作为浸提剂。通过回归正交旋转组合设计实验表明,料液比和浸提温度对蒲公英黄色素的提取影响较大。在优化条件下料液比1∶40(g/mL)、温度50℃、乙醇浓度70%下测得的最大OD值为0.816。     

栀子黄色素的提取及精制研究

本文通过正交试验,确定了超声波法提取栀子黄色素的最佳工艺条件为:乙醇溶液60%、温度为45℃、提取时间20min。同时,本文对几种大孔树脂对栀子黄色素的精制条件和效果进行了研究。结果表明:D3520、D140树脂的精制效果较好,适合制备高色价的栀子黄色素。经D140树脂精制后的栀子黄色素的色价达到401,得率为1.80%;经D3520树脂精制后的栀子黄色素的色价达到434,得率为1.33%。二者比较,D3520精制的栀子黄色素的色价略高,OD比值略低,而D140树脂的吸附容量更大。     

栀子黄色素的提取及精制研究

通过正交试验,确定了超声波法提取栀子黄色素的最佳工艺条件为:乙醇溶液60%、温度为45 ℃、提取时间20 min.同时,对几种大孔树脂对栀子黄色素的精制条件和效果进行了研究.结果表明:D3520、D140树脂的精制效果较好,适合制备高色价的栀子黄色素.经D140树脂精制后的栀子黄色素的色价达到401,得率为1.80%;经D3520树脂精制后的栀子黄色素的色价达到434,得率为1.33%.二者比较,D3520精制的栀子黄色素的色价略高,OD比值略低,而D140树脂的吸附容量更大.     

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.     

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.     

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.     

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.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.