超声波辅助碱提沁洲黄小米多糖工艺条件优化

以沁州黄小米为材料,采用超声波辅助碱提法提取其中的多糖。用单因素试验来考察碱液浓度、超声功率、超声时间和液固比在提取过程中对沁州黄小米多糖得率的影响。正交试验结果表明这4个因子对沁州黄小米多糖得率影响作用大小顺序为:液固比超声波处理时间超声功率碱液浓度;得到的多糖提取最佳工艺条件组合:碱浓度0.8 mol/L,超声波处理时间15 min,超声功率97.5 W,液固比30∶1(m L/g),此优化工艺条件下多糖的得率达到70.29%。该研究为沁州黄小米中多糖物质的最优化提取和利用提供参考。     

忧遁草活性物质超声辅助提取工艺的优化

以多酚、黄酮、三萜和维生素C 4种活性物质为指标,研究超声时间、超声温度、料液比和超声功率对忧遁草中活性物质提取效果的影响,利用正交试验优化超声辅助提取忧遁草活性物质的最佳工艺条件。试验结果表明料液比和超声时间对多酚、黄酮和维生素C得率的影响较大;超声功率和超声时间对三萜得率影响较大。通过四因素三水平的正交试验,确定了忧遁草中4种活性物质提取的最佳条件,得出超声辅助提取的最优提取工艺是:超声时间40 min,超声温度45℃,料液比1∶55(mg/m L),超声功率156 W。在此条件下4种活性成分的得率分别为:多酚9.387 mg/g,黄酮28.785 mg/g,三萜23.665 mg/g,维生素C 0.216 mg/g。     

黄金茶中总黄酮超声提取工艺

对超声法提取黄金茶中总黄酮的工艺进行优化。利用超声法提取黄金茶中的总黄酮,考察了超声时间、超声功率、乙醇浓度、料液比4个因素对总黄酮得率的影响,通过单因素试验和正交试验确定了提取的最佳提取工艺条件。最佳提取工艺为超声时间20min,超声功率75W,乙醇浓度70%,料液比1∶20(g/mL),总黄酮得率为5.3493%。     

响应面法优化红景天苷超声波辅助提取工艺

采用超声波辅助提取长白山红景天中主要活性物质红景天苷,在单因素试验基础上,选择提取时间、料液比、超声波功率、提取温度4个因素进行响应面分析。结果表明,最佳工艺参数为提取时间60 min、超声功率405 W、提取温度72℃、料液比1∶16(g/m L)。在此条件下,红景天苷得率为2.85%。模型显示各因素对红景天苷的得率的影响大小依次为料液比温度超声功率提取时间。     

北五味子挥发油提取工艺及抗氧化性的研究

以北五味子为原料,利用超声波辅助提取北五味子挥发油,研究了超声功率、时间、温度、固液比对北五味子挥发油得率的影响。试验结果表明:影响北五味子挥发油得率主次因为为超声功率时间温度固液比,最佳提取工艺条件为超声功率800 W、超声时间10 min、超声温度60℃、料液比(g/mL)为1∶14,在此工艺条件下北五味子挥发油得率可以达到3.09%。DPPH清除试验表明:北五味子挥发油的抗氧化性较VE要强好,但弱于VC。     

超声强化水蒸气蒸馏提取神香草精油的工艺

研究利用超声强化水蒸气蒸馏法提取神香草精油的工艺,分析超声强化时间、超声功率、液固比、提取时间对精油得率和品质的影响,通过正交试验确定最佳工艺条件,各因素对神香草精油得率影响程度是:超声功率超声强化时间提取时间液固比。优化的工艺条件为超声功率160 W、超声强化时间15 min、液固比15∶1(m L/g)、提取时间1 h,神香草精油得率为0.738%     

超声预处理-柠檬酸辅助亚临界水提取麦麸水溶性膳食纤维工艺优化

采用超声预处理-柠檬酸辅助亚临界水提法从小麦麸皮（以下简称“麦麸”）中提取水溶性膳食纤维。通过单因素实验考察超声预处理功率、柠檬酸/麦麸液固比、亚临界水提取温度和时间对麦麸水溶性膳食纤维得率的影响,在此基础上,采用响应面优化法,对提取工艺参数进行优化。结果表明,最佳提取条件为:超声预处理功率195 W,柠檬酸/麦麸液固比39:1 mL/g,亚临界水提取温度和时间分别为179 ℃和30 min。此时,麦麸水溶性膳食纤维的得率为41.00% ± 0.29%。因此,该方法能够提高麦麸水溶性膳食纤维的得率,且具有提取时间短、绿色、环保等优点,为工业化生产麦麸水溶性膳食纤维提供技术参考。     

超声波辅助萃取豆渣中可溶性大豆多糖工艺

对豆渣中水溶性大豆多糖进行超声辅助萃取,以获得其超声辅助萃取大豆豆渣多糖的优化工艺。以豆渣为原料,在pH值为6.0的条件下,从提取时间、液固比、超声功率及提取温度等因素分析其对豆渣可溶性大豆多糖得率的影响,并通过正交试验优化超声波辅助萃取豆渣中可溶性大豆多糖的工艺。最佳萃取工艺条件为:液固比20∶1、温度60℃、时间30min及功率70W。此条件下豆渣中可溶性大豆多糖提取率可达到最大,为0.019%。在影响大豆豆渣多糖提取率的4个因素(提取温度、液固比和提取时间、超声功率)中,液固比、提取时间为主要因素,其次是温度和超声功率。超声波辅助萃取可有效提高豆渣中可溶性大豆多糖得率。     

超声辅助吐温80提取发芽小米GABA和多酚的工艺优化

采用超声辅助吐温80优化发芽小米γ-氨基丁酸（gamma-amino butyric acid,GABA）和多酚提取工艺。以GABA和多酚得率为考察指标,通过单因素试验探究吐温80质量分数、超声温度、超声时间、料液比、超声功率对GABA得率的影响,设计正交试验优化GABA提取工艺;通过单因素试验探究吐温80添加量、超声温度、超声时间、料液比4个因素对多酚得率的影响,以响应面试验设计优化多酚提取工艺。结果表明：超声辅助吐温80提取GABA的最佳工艺条件为吐温80质量分数6%、超声温度35℃、超声时间25 min、料液比1∶18（g/mL）、超声功率126 W,此条件下GABA得率为4.70 mg/g;提取多酚的最佳工艺条件为吐温80质量分数9%、超声温度42℃、超声时间19 min、料液比 1∶12.5（g/mL）,此条件下多酚得率为 1.99 mg/g。     

超声波提取蚕蛹油的工艺研究

研究了超声波辅助提取蚕蛹油的工艺条件。通过单因素试验探讨了超声波功率、温度、液固比和时间4个参数对蚕蛹油得率的影响,然后通过正交试验确定了蚕蛹油的较佳提取条件。结果表明,温度对蚕蛹油得率影响较大,其次是超声波功率,时间影响最小,蚕蛹油提取的较优条件为:超声波功率120 W,温度70℃、液固比2∶1(mL/g)、时间为4 h,在上述条件下蚕蛹油得率为29.5%。     

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.