低温溶剂分提与分子蒸馏复合法富集沙棘果油棕榈油酸的工艺研究

以沙棘果油水解后的混合脂肪酸为原料,在正己烷-丙酮(体积比1∶1)与粗制混合脂肪酸体积比1∶1、分提温度-5℃、分提时间12 h下采用低温溶剂分提法富集棕榈油酸,再采用分子蒸馏法对低温分提混合脂肪酸进行富集,以达到富集沙棘果油棕榈油酸的目的。通过单因素试验对分子蒸馏条件进行优化,得到最佳的分子蒸馏工艺条件为真空度5 Pa、蒸馏温度95℃、进料速度1 mL/min、刮膜器转速220 r/min。在最佳条件下进行二次分子蒸馏,棕榈油酸含量从沙棘果油的30. 74%提高到72. 56%,轻相得率为30. 90%。进一步将产物进行低温溶剂分提后,棕榈油酸含量可达78. 30%。     

分子蒸馏精制棕榈油甘油二酯工艺研究

利用分子蒸馏小试装置研究了分离较高纯度棕榈油甘油二酯的生产工艺。利用Novozym 435脂肪酶在无溶剂体系下甘油解棕榈油,制备甘油二酯含量大于50%的酰基甘油混合物,采用两级分子蒸馏进行精制,并研究了二级分子蒸馏温度、刮膜转速、进料速率对甘油二酯纯度的影响。结果表明:在二级分子蒸馏真空度0.1 Pa、蒸馏温度230℃、刮膜转速300 r/min、进料速率4 m L/min的条件下,得到了纯度达到80%左右、得率达到50%左右的棕榈油甘油二酯产品。     

生物柴油副产物甘油精制工艺研究

以棕榈油为原料,碱法催化甲醇与棕榈油进行酯交换反应生成脂肪酸甲酯(即生物柴油)和副产物甘油。副产物粗甘油经过磷酸中和得到甘油半成品,再经过乙醇结晶、分子蒸馏得到高纯度甘油产品。通过正交实验得到乙醇结晶的最佳条件为:结晶温度20℃,结晶时间20 min,乙醇添加量为1∶1(V/W)。乙醇结晶后的甘油在温度110℃,压力30 Pa下进行分子蒸馏,得到纯度为99.5%的高纯度甘油。     

沙棘果油棕榈油酸提取物的富集及改善胰岛素抵抗活性

运用尿素包埋-分子蒸馏复合法提取沙棘果油中的棕榈油酸,在单因素试验的基础上采用响应面分析法优化提取工艺参数,并利用气相色谱法对产物脂肪酸组成进行分析。通过高浓度胰岛素诱导HepG2细胞建立胰岛素抵抗模型,探索沙棘果油提取物改善胰岛素抵抗活性。结果表明,尿素包埋和分子蒸馏两步法提取沙棘果油中的棕榈油酸最佳条件为:尿素包埋法,尿素与底物比1.98∶1(g/g)、溶剂与尿素比4.03∶1(mL/g)、包埋时间12.15 h;分子蒸馏法,进料速率0.84 mL/min、刮膜速率116.02 r/min,蒸馏温度99.75℃。采用气相色谱检测棕榈油酸含量,结果表明在最佳优化条件下棕榈油酸质量分数显著提高,达到72.19%(模型预测值为68.02%),证明所建立的方法可用于沙棘果油中棕榈油酸的富集和纯化;体外实验表明沙棘果油中棕榈油酸提取物浓度达到100μmol/L时可以明显改善糖原合成水平,达到200μmol/L时可以显著性缓解胰岛素抵抗导致的葡萄糖消耗量降低现象,证明沙棘果油棕榈油酸提取物具有改善胰岛素抵抗的功能。     

响应面法优化分子蒸馏提纯神经酸工艺的研究

应用刮膜式分子蒸馏装置对神经酸的提纯工艺进行了研究,分析了蒸馏温度、进料速率、到膜器转速三个操作因素对神经酸产品纯度及质量收率的影响.采用SAS软件程序对试验数据进行了二次响应面回归分析,对分子蒸馏工艺条件进行优化,得出分子蒸馏法提取神经酸的二次回归方程.刮膜式分子蒸馏技术提纯神经酸的优化条件为:系统压力0.1 Pa,蒸馏温度114.5℃,进料温度60 ℃,进料速率12 mL/h,刮膜器转速295 r/min.可以将原料中的神经酸由最初的6.07%提纯浓缩至39.02%,含量提高到原含量的近6.5倍.     

分子蒸馏从大豆脱臭馏出物中提取维生素E的研究

本文采用三级分子蒸馏,结合两次脱除甾醇,从大豆油脱臭馏出物中提取维生素E。3次分子蒸馏的工艺条件分别为：一次分子蒸馏,加热壁面温度100℃,进料速率3mL/min,刮板转速100r/min,预热温度80℃;二次分子蒸馏,加热壁面温度180℃,进料速率1mL/min,刮板转速50r/min,预热温度80℃;三次分子蒸馏,加热壁面温度130℃,进料速率1mL/min,刮板转速100r/min,预热温度80℃。结果表明,采用3次分子蒸馏,结合两次结晶脱除甾醇,大大提高产品纯度,产品维生素E含量可达74.55%。     

鱼油中棕榈油酸的分离纯化

采用尿素包合-分子蒸馏复合法对乙酯化鱼油的棕榈油酸进行富集.尿素包合的条件为反应温度75℃,m鱼油:m尿素:m乙醇=1:2:4.通过单因素试验研究刮膜转速、进料速度和蒸馏温度对棕榈油酸含量的影响.在单因素试验基础上,应用响应面分析优化得到分子蒸馏富集棕榈油酸的最优条件:设备真空度3.0×10-3 kPa,刮膜转速160...     

分子蒸馏分离提纯甘二酯中试工艺研究

研究了中试分子蒸馏分离提纯甘二酯的工艺方法。棕榈油在一定的条件下经过中试分子蒸馏设备蒸馏,得到重相与轻相。轻相主要是甘二酯,重相主要是甘三酯。通过进料量、温度及刮膜转速的控制可以得到纯度70%以上的甘二酯。研究结果表明,在温度220℃、压力0.01 Pa、进料量10 L/h、蒸发器转速200 r/min的条件下,通过脱气,薄膜蒸发与短程蒸馏可以得到纯度较高的甘二酯。用棒状薄层色谱―氢火焰离子化检测器法(TLC–FID)与反相高效液相色谱–蒸发光散射检测法(RP–HPLC–ELSD)分别分析测定了棕榈油以及轻相、重相中甘油酯的含量,并进行了对比;用气相色谱分析了棕榈油以及轻相、重相脂肪酸组成。     

分子蒸馏技术用于制备高纯二聚脂肪酸的工艺研究

以红花油脂肪酸为原料,通过Diels-Alde反应合成二聚脂肪酸。研究了分子蒸馏技术对反应以及蒸馏时温度、压力、进样速率对二聚酸分离效果的影响。结果表明,从含二聚酸的混合物中除去单体酸的适宜分离条件为:压力4Pa,蒸馏温度160℃,进样速率3g/min;从一次蒸馏残液中提取二聚脂肪酸的适宜条件为:压力4Pa,蒸馏温度220℃,进样速率2g/min。     

分子蒸馏提纯C22-三酸二丁一甲酯的研究

采用刮膜式分子蒸馏装置对C22-三酸二丁一甲酯进行提纯,考察了1级分子蒸馏中,蒸馏温度、蒸馏压力、进料速率和刮膜转速对C22-三酸二丁一甲酯含量和收率的影响。得到1级分子蒸馏提纯C22-三酸二丁一甲酯的适宜分离工艺条件为:蒸馏温度120℃,蒸馏压力40 Pa,进料速率1.2 g/min,刮膜转速240 r/min;在此条件下,C22-三酸二丁一甲酯的含量可达95.6%,收率为85.0%。在蒸馏压力较大情况下,采用多级分子蒸馏可提高产品C22-三酸二丁一甲酯含量,但收率下降,当蒸馏压力增大为80 Pa时,经4级分子蒸馏后,C22-三酸二丁一甲酯含量可达到96.5%,收率由1级分子蒸馏的93.9%下降至78.0%。提纯产物经红外光谱和质谱分析,确定产物为目标产物C22-三酸二丁一甲酯。     

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