超临界二氧化碳抗溶剂法制备玉米蛋白纳米颗粒

采用超临界二氧化碳抗溶剂法从玉米蛋白的丙酮-二甲亚砜混合溶液中制得了玉米蛋白纳米颗粒,考察了温度、压力、溶液浓度、二氧化碳流速和溶液流速对玉米蛋白空白微球形貌和粒径的影响。用扫描电镜、纳米粒度分析、热重分析、差热分析等手段对结果进行表征。实验结果表明,超临界CO2抗溶剂法可用于制备球形度较好、粒径分布较窄的玉米蛋白微球,所得玉米蛋白微球平均粒径在160～400nm之间。温度、压力、溶液浓度都会影响微粒的粒径,选取不同的工艺组合可制备不同粒径及分布要求的微粒。热重分析和差热分析的结果显示,制得的玉米蛋白空白微球较原料稳定性有所提高。      

超临界二氧化碳抗溶剂法制备玉米蛋白纳米颗粒

采用超临界二氧化碳抗溶剂法从玉米蛋白的丙酮-二甲亚砜混合溶液中制得了玉米蛋白纳米颗粒,考察了温度、压力、溶液浓度、二氧化碳流速和溶液流速对玉米蛋白空白微球形貌和粒径的影响。用扫描电镜、纳米粒度分析、热重分析、差热分析等手段对结果进行表征。实验结果表明,超临界CO2抗溶剂法可用于制备球形度较好、粒径分布较窄的玉米蛋白微球,所得玉米蛋白微球平均粒径在160～400nm之间。温度、压力、溶液浓度都会影响微粒的粒径,选取不同的工艺组合可制备不同粒径及分布要求的微粒。热重分析和差热分析的结果显示,制得的玉米蛋白空白微球较原料稳定性有所提高。     

超临界流体强制分散溶液技术制备叶黄素超细微粒

以二氯甲烷为溶剂,以超临界二氧化碳为抗溶剂,采用超临界流体强制分散溶液(SEDS)过程对天然叶黄素进行了超细化研究。粒径约50μm的块状叶黄素晶体经SEDS过程处理后变为粒径3 20μm的棒状、缠绕纤维状的超细微粒。利用扫描电镜和光学显微镜分析测试了叶黄素超细微粒的粒径和形态,详细讨论了溶液浓度,溶液流量,压力和温度等操作参数对叶黄素超细微粒的粒径和形态的影响。结果表明溶液浓度,溶液流量和温度对超细微粒的粒径影响较大,而压力基本没有影响。     

超临界CO2抗溶剂结晶葛根素工艺参数优选

根据前期研究结果,对采用响应曲面法关于结晶压力、温度和时间建立超临界CO2抗溶剂结晶葛根素工艺模型的变化规律进行响应曲面分析,并优选出最佳工艺参数,便于选择超临界CO2抗溶剂结晶葛根素条件。结果表明:当结晶压力为22.12MPa,温度为32.35℃,时间为2.17h时,葛根素纯度高达57.55%。     

超临界快速膨胀法制备聚乙烯蜡超细颗粒

以CO2为溶剂,聚乙烯蜡为溶质,采用超临界溶液快速膨胀法(RESS)制备了聚乙烯蜡超细颗粒。考察了预膨胀温度、预膨胀压力、收集距离等工艺条件对颗粒平均粒径的影响。结果表明,采用较高的预膨胀压力、预膨胀温度有助于获得平均粒径较小的超细粒子;在收集距离50 mm     

葛根素超临界CO2抗溶剂结晶模型建立

选择葛根提取物(葛根素含量10%)为实验原料,采用超临界CO2抗溶剂结晶法进行高效提纯葛根素研究。具体考察压力、温度、时间的影响,并采用高效液相色谱法检测样品纯度。采用响应曲面法对超临界CO2抗溶剂结晶葛根素的三个主要工艺参数压力、温度和时间进行了实验设计,并建立了相关数学模型,结果表明实际值与模型预测值偏差为3.37%。     

乙基纤维素-蜂胶缓释微囊的研究

以乙基纤维素为囊材,采用物理化学法制备蜂胶微囊。对蜂胶微囊的形态、粒径分布、释放性能等进行了研究。该法所制蜂胶-乙基纤维素微囊圆整度好,并具有较好的缓释性能。溶出曲线和微囊形貌结构照片研究表明,可能至少存在两种不同的溶出释放通道。     

响应面设计优化超临界CO2抗溶剂法制备负载β-胡萝卜素的玉米蛋白纳米粒

利用响应面设计对超临界CO2抗溶剂法制备负载β-胡萝卜素的玉米蛋白纳米粒的工艺进行研究。分别以β-胡萝卜素的负载量和包埋率为优化指标,系统考察芯材比、温度、压力等主要因素对玉米蛋白包埋β-胡萝卜素的交互影响,采用SEM、DLS和XRD对产品形貌、粒径和结构等进行表征。结果表明：芯材比对载药量和包埋率的影响最显著,其次是压力,最后是温度。当芯材比1:10(质量比)、温度55℃、压力8MPa时,β-胡萝卜素的负载量达到最大值8.73%;当芯材比1:30、温度35℃、压力16MPa时,β-胡萝卜素的包埋率有最高值85.4%。玉米蛋白和β-胡萝卜素形成Matrix结构,颗粒平均粒径大约150nm,粒径分布窄,球形度好。     

功能性乙基纤维素复合微球的制备及性能

将聚N-异丙基丙烯酰胺、Fe₃O₄纳米颗粒和染料4-甲胺基-9-烯丙基-1,8-萘酰亚胺与乙基纤维素溶液共混,利用高压静电喷雾技术一步法制得兼具温敏性、磁性和荧光性的乙基纤维素复合微球。结果表明,制备的乙基纤维素复合微球平均粒径在亚微米级,Fe₃O₄纳米颗粒的添加提高了复合微球的骨架强度和改善了微球形貌。当温度超过聚N-异丙基丙烯酰胺的低临界溶解温度时,乙基纤维素复合微球的平均粒径减小,表现出温敏性;基于微球的温敏响应,乙基纤维素复合微球表现出与染料溶液相反的温致荧光增强性能。振动样品磁强计分析结果表明,乙基纤维素复合微球具有良好的超顺磁性。     

过碳酸钠微囊的制备研究

探讨了有机溶剂相分离法制备过碳酸钠微囊。用乙基纤维素、聚乙烯为包覆材料，环己烷为介质， 通过改变溶液温度可制得过碳酸钠微囊。结果表明， 制备的过碳酸钠微囊， 与洗衣粉复配， 有良好稳定性。     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press