黑胡萝卜色素酸水提取工艺条件的研究

以黑胡萝卜为原料,采用酸水提取的方法,通过单因素及正交实验研究诸多因素对黑胡萝卜色素提取效率的影响.结果表明,各因素对黑胡萝卜色素提取效果的影响程度依次为浸提液酸度＞浸提温度＞料液配比＞浸提时间.确定了酸水提取黑胡萝卜色素的最佳工艺条件为浸提液酸度pH=1、浸提温度70℃、料液比1 ∶ 6、浸泡时间1.5h、浸提级数1.     

黑胡萝卜色素酸水提取工艺条件的研究

以黑胡萝卜为原料,采用酸水提取的方法,通过单因素及正交实验研究诸多因素对黑胡萝卜色素提取效率的影响.结果表明,各因素对黑胡萝卜色素提取效果的影响程度依次为浸提液酸度＞浸提温度＞料液配比＞浸提时间.确定了酸水提取黑胡萝卜色素的最佳工艺条件为浸提液酸度pH=1、浸提温度70℃、料液比1∶6、浸泡时间1.5h、浸提级数1.     

黑玉米色素提取方法的研究

以黑玉米为原料 ,通过单因子试验研究了诸多因素对提取色素效率的影响。结果表明 ,提取最优方案是以等体积 95 %乙醇与 0 .1mol/ L HCl的混合物为浸提剂 ,按黑玉米与浸提剂重量比 1∶ 4投料 ,在 80℃下浸提两次 ,每次 2 4h,提取总效率达 18.4%     

黑花生衣色素的提取工艺条件研究

以黑花生皮为原料,采用酸水浸提的方法,对黑花生皮的提取工艺条件进行研究.通过单因素及响应面试验研究诸多因素对黑花生皮色素提取效率的影响,确定黑花生皮色素提取最佳工艺条件为浸提液酸度pH1、浸提温度80℃、料液比1:50、浸泡时间2 h、提取级数2.     

野生药用植物喀什小檗色素提取工艺的研究

采用超声波、超声-微波协同、加速溶剂萃取三种方法,研究了喀什小檗色素的提取条件.结果表明,超声波法的最佳工艺为:提取剂浓度60%,料液比1:40,浸提时间30min,超声波功率500W;超声-微波协同萃取的最佳工艺为:提取剂浓度60%,料液比1:40,超声波功率500W,微波功率700W,提取时间15min;加速溶剂萃取的最佳工艺为:提取剂浓度75%,料液比1:30,氮气吹扫60s,吹扫体积30%,压力10.3MPa,静态萃取时间5min,循环1次.综合三种提取工艺,超声-微波协同萃取法用于浸提喀什小檗色素,提取条件易控制,受热体系温度均匀,提取效率较高,同时提取时间只是超声波提取法的一半,是具有良好发展前景的新工艺.     

微波辅助法提取黑糯玉米芯色素的工艺条件优化

采用微波法辅助提取黑糯玉米芯色素，改进了传统的浸提工艺，通过单因素和正交实验确定微波辅助提取的最佳工艺条件。结果表明：采用0．1mol／LHCl与95％乙醇体积比40％：60％的混合物作为提取剂、微波功率为560W、提取时间为30s、料液比为1：10、进行3次浸提效果最佳，色素提取率达94.12％。与传统的浸提法相比，时间由24h缩短为30s，色素产率由15.2％增加为16．87％，微波辅助提取色素具有时间短、耗能低、提取率高等优点。     

玉米黄色素提取工艺及其助提条件的研究

对玉米黄色素的相关提取因素进行了系统研究,试验结果表明,玉米黄色素的最大吸收波长为446nm,无水乙醇对玉米黄色素的提取效果最佳;采用正交试验确定的最佳浸提工艺条件为:提取液的pH值7.0、提取料液比1∶7、提取温度60℃、浸提时间5h。在以上提取条件的基础上,以预浸、超声破碎提取作为辅助提取条件,提取效果更好。     

新疆紫花苜蓿中黄酮类色素的提取研究

在不同溶剂、提取时间、温度、固液比和浸提次数等条件下,通过单因素实验确定正交实验的参数,对新疆紫花苜蓿中黄酮类色素提取最佳工艺条件进行了研究.结果表明,最佳的浸提条件为:浸提剂选用70%乙醇,料液比为1:50,浸提温度为80℃,浸提时间为4h,浸提次数为2次.     

枸杞色素提取工艺的研究

利用有机溶剂浸提枸杞子中的色素，通过单因素和正交实验确定了提取枸杞色素的工艺条件为：用石油醚-丙酮(体积比为4：1)混合溶剂浸提，液料比为3mL：1g，在50℃浸提1．5h，反复4次，浸提率可达91．6％。     

紫甘蓝紫色素萃取工艺条件研究

以新鲜紫甘蓝为原料,采用酸性乙醇提取天然的紫甘蓝色素.通过单因素及正交实验,结果表明,提取紫甘蓝色素各因素影响顺序为:固液比＞浸提时间＞浸提剂比例＞浸提温度,最佳工艺条件为:A1 B2 G2 D2,即固液比为1g:2mL;浸提时间4 h;75％乙醇:0.4％乙酸(体积比)为2:1;温度35℃,提取率为12.4％.     

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