微波-超声协同提取废弃绿豆种皮中的绿色素

以绿豆芽生产中废弃的绿豆种皮为原料,采用微波-超声波协同提取绿豆种皮色素;通过紫外-可见光谱、高效液相色谱和荧光光谱,初步判定绿豆皮色素的成分;研究了影响绿豆皮色素稳定性因素.结果表明,绿豆皮色素提取的最佳工艺是:乙醇体积分数80%,温度80℃,时间15 min,微波功率30 W,超声协同;初步判定绿豆皮色素的主要显色成分为叶绿素;绿豆皮色素在温度小于80℃、pH=7～9时比较稳定;Fe~(2+)、Fe~(2+)、Al~(3+)等金属离子对绿豆皮色素稳定性影响较大,遇Cu~(2+)、Zn~(2+)离子分别有沉淀生成;随氧化剂的增大,色素吸光度有变小趋势,这可能是氧化剂破坏绿豆皮色素中的不饱和键所致;还原剂对该色素吸光度的影响很小,常用食品添加剂对该色素无太大影响.     

响应面优化超临界法萃取绿豆皮黄酮工艺

采用超临界CO2技术萃取绿豆皮中黄酮类物质,通过单因素和响应面试验对超临界萃取绿豆皮黄酮工艺参数进行优化,结果表明:当萃取压力31 MPa、萃取温度47℃、萃取时间3.58 h、原料/夹带剂=1∶0.62(g/m L)时,绿豆皮黄酮的萃取率最高为87.64%。影响黄酮萃取率由强到弱的因素依次为萃取温度萃取压力萃取时间原料/夹带剂。     

花生壳中木犀草素的超临界CO2萃取工艺研究

目的:研究超临界CO2萃取花生壳中木犀草素的最佳工艺条件。方法:采用HPLC法测定木犀草素含量,以提取率为指标,应用单因素和正交实验,分别考察萃取温度、萃取压力、分离温度、分离压力以及CO2流量等5个因素影响,并将筛选工艺与目前文献的乙醇提工艺进行对比分析。结果:超临界CO2萃取木犀草素的最佳工艺条件:萃取温度为50℃,萃取压力为35MPa,分离温度为30℃,分离压力为10MPa,CO2流量为7L/h。结论:与传统乙醇提取工艺相比,超临界CO2萃取工艺提取花生壳中木犀草素的提取率提高了2.63倍。     

超临界C02萃取红曲色素的工艺优化研究

以红曲米为原料,采用Box-Behnken实验设计原则,应用响应面法对超临界CO2萃取红曲色素的工艺参数进行分析,确定了超临界CO2流体萃取红曲色素的最佳工艺条件:萃取压力28MPa,萃取温度50°C,萃取时间3.7h,在此条件下,萃取物中红曲色素色价可达1628.6U/mL.     

乌桕籽皮油超临界CO2流体萃取及其成分分析

应用超临界CO2 流体萃取技术,研究了乌桕籽皮油的萃取工艺。采用正交试验,考察了萃取压力、温度、CO2 流量三因素对乌桕籽皮油萃取率的影响效果。最佳萃取条件确定为：压力40MPa,温度36℃,CO2 流量20L/h,时间1h。利用GC 分析了乌桕籽皮油的成分组成,以期为乌桕籽的综合利用提供理论依据。     

超临界CO2 萃取雪峰蜜橘橘皮精油的中试条件研究

以橘皮为原料,采用超临界CO₂ 萃取技术(SFE)提取雪峰蜜橘橘皮中精油和色素,通过正交试验确定萃取的最佳中试条件,并利用气相色谱- 质谱法(GC-MS)分析最佳中试工艺条件下生产的橘皮精油成分。结果表明：最佳中试提取工艺条件为萃取压力30MPa、萃取时间1h、萃取温度40℃、CO2 流量21.27L/min,此时提取物(色素＋精油)提取率4.56%。其中精油共检测出21 种成分,主要成分为D- 柠檬烯、α- 金合欢烯、白菖油萜、β- 榄香烯、β- 蒎烯等,其中D- 柠檬烯和α- 金合欢烯的总含量达90% 以上。     

黄花蒿蜡油叶绿素含量及其铜钠盐制备工艺

基于蜡油重要利用价值,优化蜡油叶绿素提取条件,分析蜡油叶绿素含量,设计酸化铜代、中和成盐二步法制备蜡油叶绿素铜钠工艺,并实时分析工艺效果,对蜡油叶绿素铜钠产品质量进行评价。低温(-10℃)条件下,料液比1:20~22(g:mL),以无水乙醇为溶剂萃取蜡油叶绿素为最佳萃取条件;蜡油叶绿素含量为3.0%;经酸化铜置、中和成盐二步工艺可有高效制备蜡油叶绿素铜钠,工艺产率达63.0%,产品各项重要指标符合国家标准。蜡油叶绿素含量丰富,具有开发利用价值。     

超临界CO2萃取芦蒿挥发油的正交试验及GC-MS分析

目的:确定芦蒿挥发油超临界CO2萃取的最佳条件,并对挥发油中化学成分进行分析.方法:采用超临界CO2萃取芦蒿挥发油的正交试验,研究其萃取工艺条件,探讨萃取压力、萃取温度、萃取时间、CO2夹带剂用量对挥发油收率的影响,并用气相色谱-质谱联用技术对其挥发油中化学成分进行分析.结果:确定了超临界CO2萃取芦蒿中挥发油的最佳条件:萃取压力40MPa,萃取温度45℃,萃取时间3h,夹带剂用量1.5ml/g,在最佳条件下芦蒿挥发油的收率为3.12%;气相色谱-质谱联用技术从芦蒿挥发油中共分离出45个峰,确定了其中的37种化合物,经峰面积归一化法测定了各组分的相对百分含量,所鉴定成分占总馏出峰面积的93.12%.主要成分蓝香油薁具有多种较强的生理活性.结论:本研究结果为芦蒿的进一步综合开发利用提供科学依据.     

小叶丁香超临界CO2萃取工艺及提取物GC-MS分析

通过采用正交试验,对超临界CO2萃取小叶丁香的工艺进行优化研究,并用GC-MS对提取物成分进行分析.结果表明:最佳提取工艺为萃取压力25MPa,萃取温度45℃,超临界CO2流体流量18 L/h,萃取时间2.5 h;从小叶丁香提取物中鉴定出30种成分,其中9,12-十八碳二烯酸含量最高(19.6%),显示了优良的保健价值.     

超临界流体萃取茶叶香气成分的研究

采用超临界流体萃取技术提取茶叶中的香气成分,研究温度、压力、时间、CO2流量对超临界流体萃取得率的影响,通用正交实验法进行最佳工艺优化并对产物进行GC/MS定性分析.结果表明:萃取时间4 h、萃取温度50 ℃、CO2流量8 L/h、萃取压力30 MPa时得率为2.82%,共鉴定出28种香味成分.     

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.