秋橄榄果实多酚提取工艺研究

以野生秋橄榄为原料,采用4因素3水平正交试验设计对其果实多酚提取工艺进行了研究。结果表明,在检测的4个因素中乙醇浓度对秋橄榄果实多酚的提取效率影响最大,其次为料液比、提取温度和提取时间。在超声波功率为70%的条件下,果实多酚提取的最佳工艺参数为30%乙醇、1:20料液比、40℃、每次15 min。     

正交设计优选油橄榄叶中多酚的提取工艺

以油橄榄叶片为原材料,优选多酚的提取工艺。以焦性没食子酸为对照品,通过乙醇浓度、提取料液比、提取时间、提取温度4因素,以多酚提取率为指标,先通过单因素试验,然后采用正交试验优选提取工艺条件。最佳提取工艺条件为乙醇浓度为70%、提取料液比为1:30、提取时间为1.5 h、提取温度为70℃。在最佳条件下多酚的提取率为3.265%。表明该提取工艺简单、合理。     

基于高效液相色谱-三重四极杆质谱分析番石榴叶多酚组分提取方法的研究

目的优化番石榴叶多酚组分的回流提取条件,为其工业化生产提供参考。方法建立番石榴叶9种已知多酚的高效液相色谱-三重四极杆质谱分析方法,在此基础上,以已知多酚提取率为考察指标,对料液比、提取液中乙醇体积分数、提取温度、提取时间和筛网目数进行单因素试验,然后,在单因素试验的基础上,选择对多酚提取率影响较大的4个因素(料液比、乙醇体积分数、提取温度和提取时间)设计四因素四水平正交试验,确定最优提取工艺条件。结果番石榴叶多酚最优提取条件为:料液比1:25 g/mL,乙醇体积分数60%,提取温度70℃,提取时间3 h。最优提取条件下提取率为2.352 mg/g。结论建立的番石榴叶多酚组分液质分析方法有效、可靠,优化得到的提取方法提取率高、重复性好。     

正交设计优化芒果核仁多酚的微波提取工艺

研究在不同的实验条件下,芒果核仁中芒果多酚的微波提取率,确定最佳提取提取工艺。采用单因素试验、正交试验方法,以微波提取法提取红象牙核仁的芒果多酚,确定红象牙核仁芒果多酚的最佳提取工艺条件。影响芒果多酚提取工艺因素次序为:提取温度料液比乙醇浓度提取时间。最佳工艺为:70%乙醇,料液比(g∶m L)1:15,微波提取温度60℃,提取时间60 s。优化出的微波提取工艺条件稳定、可行。     

响应面法优化油橄榄叶中橄榄苦苷超声辅助提取工艺

目的:研究油橄榄叶中橄榄苦苷超声辅助提取最佳工艺条件。方法:选定甲醇体积分数、料液比和提取时间作为影响因素,以橄榄苦苷提取率为评价指标。在单因素试验的基础上,通过3因素3水平Box-Behnken试验,建立橄榄苦苷提取率的二次多项式回归方程,经响应面回归分析得到优化组合条件。结果:最佳工艺条件为甲醇体积分数93.5%、料液比1:25(g/mL)、提取时间26min。结论:油橄榄叶中橄榄苦苷提取率可达7.83%。     

银杏叶多酚超声辅助提取工艺及其对羟自由基的清除作用

以银杏叶为原料,采用超声辅助乙醇提取银杏叶多酚。在利用单因素试验对影响银杏叶多酚提取率的4个因素(乙醇浓度、料液比、提取温度和超声时间)考察基础上,以多酚提取率为响应值,采用Box-Behnken试验设计与优化,分析提取过程中工艺参数对提取率的影响,并以多酚对羟自由基的清除作用来衡量其抗氧化性。结果表明,银杏叶多酚的最佳提取工艺为:乙醇浓度74%、料液比1:25(g/mL)、提取温度62℃、超声时间30 min,在此条件下银杏叶多酚提取率为8.32%。所提取的银杏叶多酚对羟自由基的清除效果高于VC,且与浓度呈正相关。     

超声波辅助提取苹果渣多酚工艺

研究了超声波辅助提取苹果渣中多酚的工艺,利用二次回归正交旋转组合设计考察了乙醇体积分数、料液质量体积比、提取温度、提取时间对苹果渣中多酚物质提取率的影响;试验结果表明,各因子对提取率的影响大小依次是提取温度＞料液质量体积比＞提取时间＞乙醇体积分数;最佳提取工艺条件是:乙醇体积分数50%、料液比1 g:20 mL、提取温度60℃、提取时间24min;此条件下苹果多酚的提取率为3.80 mg/g.     

响应面优化薏米多酚提取工艺

采用超声法提取薏米多酚,以没食子酸为标准品、福林酚为显色剂,比色法测定多酚含量。在单因素试验基础上,利用Box-Behnken响应面分析法对薏米多酚提取工艺中的各因素进行优化。结果表明:薏米多酚提取率影响因素为提取温度料液比提取时间溶剂体积分数;当溶剂体积分数63.2%、提取温度54℃、料液比1∶21.1(g/mL)、提取时间33.6 min时,薏米多酚提取率理论预测值为76.93 mg/100 g。最佳优化工艺条件下进行实验验证,薏米多酚提取率为72.75 mg/100 g,实测值与理论预测值之间具有良好的拟合度,回归模型切实可行,优化的工艺条件适合薏米多酚提取。     

响应面法优化美味牛肝菌多酚的提取工艺研究

以美味牛肝菌为原料,研究不同液料比、乙醇体积分数、提取时间、提取温度和提取次数对多酚提取率的影响,并在单因素试验结果的基础上,通过响应面法优化美味牛肝菌多酚的提取工艺。结果表明,美味牛肝菌多酚的最佳提取工艺条件为:液料比37(mL/g),乙醇体积分数57%,提取时间90 min,提取温度45℃,提取2次,在此条件下多酚的提取率为1.33%±0.02%。试验结果为美味牛肝菌多酚的生物活性研究及功能调味料开发提供了一定的技术参考。     

响应面法优化花椒叶多酚提取工艺及其抗氧化活性

以花椒叶为原料,对花椒叶多酚提取工艺及其抗氧化活性进行研究.通过单因素试验分析料液比、提取温度、提取时间对花椒叶多酚提取率的影响,在单因素试验基础上,利用响应面法优化提取工艺.优化得到各因素最佳参数为料液比1:56(g/mL)、提取温度81℃、提取时间107 min,验证试验所得实际多酚提取率为4.63％,与预测值接近...     

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.     

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.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the