炮仗花色素提取工艺优化及其色素稳定性研究

以炮仗花为实验原料,通过单因素试验和L9(33)正交试验,对炮仗花色素的提取工艺进行了优化,并对色素的稳定性进行了研究。研究结果表明,炮仗花最佳提取工艺为:丙酮为浸提剂,料液比1:10、提取温度60℃、浸提时间10h。该色素有较好的耐热性,较强的耐氧化和耐还原能力,在弱碱和弱酸性条件下保持稳定;多数食品添加剂和金属离子对色素无不良影响,但Fe3+、淀粉及日光对色素有一定影响。     

金盏菊花中色素的提取工艺及稳定性研究

目的：确定金盏菊花色素的最佳提取工艺,并对其稳定性进行研究。方法：以浸提法对金盏菊花中的色素进行提取,通过对提取剂、料液比、提取温度、提取时间4因素进行,L9(34)正交试验得到最佳提取条件;同时考察光照、热和食品添加剂等对色素稳定性的影响。结果：金盏菊花色素最佳提取工艺为提取剂90%乙醇、料液比1:8(g/mL)、在70℃水浴中浸提40min;该色素在酸性条件下稳定性较好,对光和热稳定性好;pH值对色素的稳定性影响较大,在酸性条件(pH5)下该色素较稳定;常用食品添加剂如葡萄糖、蔗糖对色素的色泽无不良影响,金属离子Na+、Mg2+、Ca2+、Cu2+对金盏菊花色素无不良影响,而Fe3+则对色素有明显影响。结论：获得金盏菊花中色素提取的最佳工艺;色素对光、热、常用食品添加剂的稳定性良好,为其在食品和药品中的应用提供了广阔的前景。     

大叶红草色素的提取及其稳定性研究

以大叶红草为实验原料,对大叶红草天然色素的提取工艺和稳定性进行研究。采用L（934）正交试验研究色素的最佳提取工艺;用紫外-可见分光光度分析法研究色素的稳定性。结果：得到常规法提取大叶红草红色素的优化工艺,蒸馏水为浸提剂,料液比1∶20;提取温度40℃;浸提次数3次,每次浸提时间是60min;结论：大叶红草色素为紫红色,颜色鲜艳,该色素适应pH（10≥pH≥4）较宽,光稳定性、耐氧化性较好,热稳定性、耐还原性较差,常用食品添加剂对色素的色泽无不良影响,Mg^2＋、Mn^2＋、Zn^2＋、Ca^2＋和低浓度的Cu^2＋对色泽无影响,Na^＋、K^＋和Fe^3＋有不良影响。     

榴莲果皮黄色素的提取及其稳定性的研究

文章以榴莲果皮为原料提取榴莲皮黄色素,在单因素循环的基础上,进行L9(33)正交试验,最后测试了色素的稳定性。结果表明,色素提取的最佳工艺为:提取剂为乙酸乙酯、液料比1∶30、浸提温度50℃,提取时间4h。稳定性研究表明:(I)温度、氧化还原剂、金属离子及各类常用的食品添加剂的对该色素稳定性影响较小,其中柠檬酸有增色的作用,金属离子中Fe3+,Cu2+对色素影响较大,且有一定的减色作用;(II)日光对色素的影响较大,所以在储存过程中应避免阳光直射;(III)pH对色素有一定的影响,在pH接近12时,色素明显变色。     

茄子皮色素的最佳提取工艺和稳定性研究

以食用紫茄子皮为原料,采用浸提法提取、分光光度法研究茄子皮色素的最佳提取工艺,实验结果表明提取紫茄子皮色素的最佳工艺条件是:以蒸馏水为浸提剂,液固比为50:1(mL,g)、浸提3 h、漫提温度为40℃、浸提酸度为pH 4.对所提取色素进行稳定性研究表明:温度、光照、食品添加剂对其影响较小,而部分金属离子如Ca2 ,Ba2 ,Al3 对其影响较大.     

山竹壳色素稳定性研究

考察光照、温度、氧化还原剂、酸碱度和食品添加剂等对山竹壳色素稳定性的影响.结果表明:该色素在可见光区的最大吸收波长为478 nm,70%乙醇为最佳浸提剂;该色素是一种醇溶性色素,适宜于偏酸性、中性和弱碱性条件下使用;有较强的耐氧化性和一定耐热性;金属离子Ca2+、Mg2+、Na+、Cu2+及食品添加剂如苯甲酸钠、柠檬酸、Vc,及氯化钠试剂几乎不影响山竹壳色素的稳定性.紫外光、室外日光、Fe3+、还原剂、碳酸氢钠和葡萄糖对该色素有一定减色作用.     

白杜果肉黄色素的提取及其稳定性研究

对白杜果肉黄色素的制备工艺及其稳定性进行初步研究.通过有机溶剂萃取法来制备白杜黄色素,其工艺条件为:料液比为1:5的乙酸乙酯做提取剂,提取温度为60℃,提取时间为2h.研究表明该色素在pH=3～7、温度低于80℃和氧化荆的作用下皆较稳定,在日光照射和还原剂作用下稳定性差,几种常见金属离子除Fe3+、Cu2+外均对色素无明显的不良影响,葡萄糖、蔗糖等几种食品添加剂对色素亦无不良影响且柠檬酸能使色素增色.     

叶子花红色素的提取及其稳定性研究

以叶子花苞叶为原料提取红色素,经正交试验选择最佳提取条件,并对光、温度、pH值、氧化还原介质、6种金属离子和4种食品添加剂对色素稳定性的影响进行了研究。结果表明,叶子花红色素为水溶性花青素的花色苷,在可见光区的最大吸收波长λmax=541nm。最佳提取条件为:以5%乙醇为提取剂,配料比为1:15,25℃下保温浸提3次,每次1h。该色素在70℃以下稳定性较好,对光的耐受性较差;色素在酸性条件下稳定,耐还原性强,但耐氧化性较差。6种金属离子中,Cu2+、Zn2+、Fe3+对色素有明显的破坏作用,而Mn2+、Mg2+、Al3+对色素稳定性较好,并有不同程度的护色作用。葡萄糖、NaCl、VC、苯甲酸钠对色素无不良影响。     

朱砂七色素提取及其稳定性研究

本文以中药朱砂七为原料,通过提取溶剂的选择和料液比、提取温度和提取时间的单因素分析,选取不同因素水平进行正交实验,以紫外—可见分光光度计法测定吸光度,以吸光度值为考察指标进行分析.同时研究了光照、温度、pH、氧化剂和还原剂、食品添加剂和金属离子对朱砂七色素的稳定性影响.结果表明:朱砂七色素最佳提取工艺为:70％乙醇为浸提溶剂,料液比1:6,50℃时浸提90min;朱砂七色素光稳定性、热稳定性和耐氧化性较好,低浓度的还原剂溶液中色素的耐还原性较好,在弱酸至中强度碱(6 ＜pH＜10)条件下稳定,对葡萄糖和柠檬酸等食品添加剂稳定,碳酸氢钠有不良影响,金属离子Na+、Zn2+、Mg2+、K+对色素几乎没有影响,Ca2、Fe3、Cu2+对色素有较大影响.     

大高良姜姜皮红色素的提取及其理化性质分析

以大高良姜姜皮为原料提取大高良姜姜皮红色素,并对大高良姜姜皮红色素的稳定性进行研究.结果表明,色素最佳提取工艺为:提取剂1%盐酸乙醇(V/V),浸提温度为5℃,时间为5h,料液比为12 700,稳定性研究表明,该色素对热和还原剂的稳定性较好.日光对色素的影响很大,所以在储存过程中应避免阳光直射.常用的食品添加剂如糖类,Vc对色素的光泽无大的不良影响,其中苯甲酸钠,柠檬酸,山梨酸钾对色素的影响相对较大,因此其用量不宜过多;金属离子中Fe3+,Zn2+,Cu2+对色素影响较大,其中Zn2+离子有一定的增敏作用,其他如,K+,Ca2+,Mg2+,Na+,Al3+对色素无不良影响.该色素耐酸性强,但不耐强碱,在pH值接近12时,色素明显变色.     

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