大豆胚芽中异黄酮和皂甙的提取工艺

大豆异黄酮和大豆皂甙是大豆中的活性成分.从大豆中提取这两种物质的工艺条件,通过溶剂对比实验、单因素实验确定了从大豆粕中提取大豆异黄酮和大豆皂甙的最佳工艺,并通过正交实验优化最佳生产工艺条件:温度55℃、固液比1:18、80%的乙醇溶液、提取时间2h、提取两次,异黄酮和皂甙得率分别为1.53%和4.07%.     

大豆胚芽中豆皂甙、异黄酮甙的提取工艺研究

通过溶剂对比实验及单因素实验确定了从大豆胚芽中同时提取出大豆皂甙和大豆异黄酮甙的最佳提取溶剂及影响浸提效果的相关因素,并通过正交实验确定了最佳提取工艺条件。     

大豆胚芽中异黄酮和皂甙同步提取工艺的研究

大豆异黄酮和大豆皂甙是大豆中的活性成分。本文主要研究了同时从大豆中提取这两种物质的工艺条件，通过溶剂对比实验、单因素实验确定了从大豆粕中提取大豆异黄酮和大豆皂甙的最佳工艺，并通过正交实验优化最佳生产工艺条件：温度55℃、固液比1：18、80％的乙醇溶液、提取时间2h、提取两次，异黄酮和皂甙得率分别为1．53％和4．07％。     

亚临界水法提取萌发大豆中的异黄酮

以萌发大豆为原料,采用亚临界水为溶剂提取其中的大豆异黄酮。通过单因素实验考察了提取温度、提取时间、液料比对大豆异黄酮得率的影响,并采用二次回归正交旋转组合设计实验建立了大豆异黄酮提取的回归模型,优化了最佳提取条件。结果表明最佳提取工艺条件为:提取时间6.5 min,提取温度137.3℃,液料比28.4∶1,此时大豆异黄酮得率的实测值为0.178 4%,预测值为0.170%,两者基本相符。     

大豆异黄酮、皂甙和低聚糖提取工艺研究

大豆异黄酮、大豆皂甙、大豆低聚糖是大豆的3种主要活性成分，本文研究了从大豆中同时提取这3种活性成分的工艺条件。经过单因素实验和正交实验，确定了合适的提取条件：50%乙醇，1：27的固液比（原料：溶剂），60℃回流5h。在此条件下提取3次，提取率接近极限。     

大豆豆粕中异黄酮提取工艺的研究

以豆粕为原料,乙醇为溶剂,得出提取大豆异黄酮的最佳路线,各因素为:70%乙醇,回流提取3次,每次3h,溶剂原料比3∶1。干膏率为32.73%,异黄酮含量22.24%。     

大豆异黄酮及大豆皂甙的抗氧化性研究

以脱脂大豆胚芽为原料,提取、分离纯化得到大豆异黄酮和大豆皂甙产品.通过超氧阴离子及过氧化氢清除实验、还原能力测定及抑制猪油氧化能力测定实验对大豆胚芽中的大豆皂甙和大豆异黄酮提取物的抗氧化性能进行了比较系统的评价.     

从大豆胚芽中提纯活性物质新方法的研究

本文探讨了以水作为介质,对大豆胚芽中的皂甙和异黄酮进行微波和超声波前处理,提取效果和纯溶剂萃取法相比,经正交实验,结果表明经450W功率微波处理30min和400W功率超声波在40篊处理45min,固液比为120,温度为60篊,时间为1h,再经40%的乙醇,浸提2次。异黄酮提取率从1.2%提高到1.74%,皂甙从4.4%提高到5.8%,比溶剂法的提取率分别提高了43%和32%,经聚酰胺柱层析分离纯化,大豆异黄酮和大豆皂甙产品纯度分别达到38%和94%。     

豆粕中大豆异黄酮的提取工艺研究

以染料木黄酮为对照物,通过对单因素实验和正交实验的比较,确定了从脱脂大豆粕中提取大豆异黄酮的最佳条件,为工业提取大豆异黄酮提供了参考依据。提取的最佳条件为乙醇浓度75%、浸提时间6h、浸提温度85℃、物料比1∶18。     

醇洗大豆浓缩蛋白副产物糖蜜中提取大豆异黄酮的研究

以醇洗大豆浓缩蛋白副产物糖蜜为原料,在对浸提溶剂单因素实验的基础上,优选丙酮作溶剂从糖蜜中提取大豆异黄酮。在对丙酮浸提温度、浸提时间、料液比单因素实验基础上,采用响应面分析法优化丙酮提取工艺条件,以大豆异黄酮提取率为响应值作响应面图。结果表明,丙酮浸提大豆异黄酮的最佳条件为浸提时间60min,浸提温度20℃,料液比1：3（m／V）,在此条件下大豆异黄酮的提取率达到90．3％,产品纯度达到23．5％。     

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.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.