向日葵花盘中绿原酸的微波辅助提取工艺条件研究

以向日葵花盘为原料,采用微波法辅助提取向日葵花盘中的绿原酸,研究可能影响绿原酸提取率的每一个因素。实验中以绿原酸的提取率为考查指标,考查乙醇浓度、料液比、微波时间、微波功率、微波温度、浸提温度、浸提时间、pH等八个因素对绿原酸提取率的影响,通过对提取过程中每一个细致因素的分析,得到较佳的工艺条件:乙醇浓度70%;料液比1∶20;微波温度60℃;微波功率300 W;微波时间6 min;浸提温度70℃;浸提时间20 min;pH值为7。此时向日葵花盘中绿原酸的提取率达到3.12%,为向日葵花盘中绿原酸的工业化微波辅助提取提供了借鉴。     

金银花中绿原酸超声微波双辅助提取工艺优化

对金银花绿原酸进行超声波和微波双辅助提取研究。以绿原酸提取率为考察对象,研究超声温度、乙醇体积分数、料液比、微波功率及辐射时间等因素对金银花绿原酸提取率的影响。结果表明:采用超声波和微波双辅助提取技术得到的绿原酸提取率较单独采用超声波或微波辅助得到的绿原酸提取率高。以体积分数70%乙醇溶液为溶剂、料液比1:15(g/mL)、50℃超声处理30min、微波功率400W、微波时间5min,得到的绿原酸提取率为5.93%。     

正交试验法优化卷心菜叶中绿原酸提取工艺研究

以卷心菜叶为原料,研究采用微波法辅助提取卷心菜叶中绿原酸的提取工艺。实验中以绿原酸的提取率为指标,以乙醇为提取剂,考察乙醇体积分数、料液比、微波温度、微波时间、微波强度等因素对卷心菜叶中绿原酸提取率的影响。通过L16(45)正交优化绿原酸提取工艺,结果显示,最佳工艺条件为:微波温度60℃、微波时间6 min、微波功率300 W、乙醇体积分数60%、料液比1∶20。在此最佳工艺条件下,卷心菜叶中绿原酸的提取率为1.2682%。     

微波超声辅助优化葵花籽粕绿原酸的提取工艺

研究了乙醇溶液为溶剂微波超声辅助提取葵花籽粕中绿原酸的优化工艺。在单因素实验的基础上采用星点设计响应面法,选择三因素(料液比、乙醇体积分数、超声时间)的最适值作为响应面优化的中心点,进行响应面分析优化提取工艺。结果表明:各因素对绿原酸得率影响的显著性顺序依次为料液比超声时间乙醇体积分数;最佳提取条件为微波功率160 W、微波时间12 s、超声功率280 W、料液比1∶19、乙醇体积分数42%、超声时间16 min,在此条件下绿原酸得率为3.095%。     

响应面法优化蓝莓叶黄酮的微波提取工艺

为确定蓝莓叶中黄酮提取的最佳工艺,以蓝莓叶为主要原料,在单因素试验基础上采用Box-Behnken 中心组合试验设计和响应面(RSM)分析法,建立微波提取黄酮的二次回归方程,并以黄酮提取率为响应值绘制响应面图和等高线图。考察乙醇体积分数、料液比、温度、微波功率及时间对黄酮提取率的影响。方差分析结果表明：乙醇体积分数、温度和微波功率对黄酮提取率影响显著;最佳工艺条件为提取温度72℃,乙醇体积分数64%,微波功率456W,在此工艺条件下黄酮提取率为4.232%。     

微波辅助PEG提取金银花叶中绿原酸的工艺优化

为了优化微波辅助聚二乙醇（PEG）提取金银花叶中绿原酸的工艺,通过单因素试验筛选提取温度、PEG-200体积分数、提取时间等关键影响因素,以绿原酸提取率为响应值设计响应面优化试验。结果表明：微波辅助PEG提取金银花叶中绿原酸的最佳工艺为微波功率350 W,微波时间70 s,料液比1∶20（g∶mL）,提取温度82 ℃,PEG-200体积分数40%,提取时间24 min,该条件下绿原酸提取率为5.87%。该工艺简单可行、快速有效、绿色环保,可用于提取金银花叶中绿原酸工业化生产。     

超声协同微波辅助提取稻壳绿原酸的工艺优化

以乙醇为提取溶剂,对稻壳绿原酸进行超声协同微波提取研究。在单因素试验的基础上,以微波时间、乙醇体积分数和料液比为自变量,绿原酸提取量为响应值,研究各自变量交互作用及其对绿原酸提取量的影响。结果表明,稻壳绿原酸提取的最佳工艺条件:微波时间34 s,乙醇体积分数52%,料液比1︰22(g/m L),超声功率160 W,超声温度80℃,超声时间20 min,在此条件下稻壳绿原酸提取量为3.94 mg/g。     

微波辅助法提取核桃青皮中的胡桃醌

研究微波辅助法提取核桃青皮中胡桃醌的最佳工艺条件。以核桃青皮为原料,对料液比、乙醇体积分数、微波时间和微波功率等因素进行研究。在单因素试验基础上,选取料液比、乙醇体积分数和微波时间为考察因素,采用L_9(3~4)正交试验设计,优化核桃青皮中胡桃醌的提取工艺。结果表明,微波功率的影响很小,其它各因子对提取率的影响大小依次是:提取时间乙醇体积分数料液比;微波辅助法提取的最佳工艺条件:料液比1∶35(g/m L),乙醇体积分数95%,微波时间25 s。胡桃醌的提取率为1.710 mg/g DW,与预测值1.706 mg/g DW基本一致。     

响应面法优化超声波辅助提取

采用超声波辅助萃取法提取文冠果种皮中的总皂苷。考察了乙醇体积分数、超声波功率、料液比、提取时间和提取温度对总皂苷提取率的影响,在单因素试验的基础上选取对总皂苷提取率影响显著的料液比、乙醇体积分数和超声波功率,利用Box-Behnken设计原理,以总皂苷提取率为响应值进行响应面试验,建立了回归方程,得到了优化的提取条件（料液比1∶30,乙醇体积分数73%,超声波功率220 W）。在提取温度50℃、提取时间90 min及优化的提取条件下,文冠果种皮总皂苷提取率达0.30%。     

响应面法优化超声波辅助提取文冠果种皮总皂苷的工艺

采用超声波辅助萃取法提取文冠果种皮中的总皂苷。考察了乙醇体积分数、超声波功率、料液比、提取时间和提取温度对总皂苷提取率的影响,在单因素试验的基础上选取对总皂苷提取率影响显著的料液比、乙醇体积分数和超声波功率,利用Box-Behnken设计原理,以总皂苷提取率为响应值进行响应面试验,建立了回归方程,得到了优化的提取条件(料液比1∶30,乙醇体积分数73%,超声波功率220 W)。在提取温度50℃、提取时间90 min及优化的提取条件下,文冠果种皮总皂苷提取率达0.30%。     

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