芝麻卵磷脂提取工艺条件研究

以芝麻浓缩磷脂为原料,利用丙酮提取除油得到芝麻粉末磷脂,再采用乙醇提取法对其中的卵磷脂(磷脂酰胆碱(PC))进行提取分离。通过单因素试验和正交试验得到最佳提取分离条件为:乙醇体积分数95%,料液比1∶12,提取温度50℃,提取时间20 min。在最佳条件下,卵磷脂提取率为27.92%,产品中PC含量为53.31%。     

高纯度磷脂酰肌醇的提取工艺研究

以低磷脂酰胆碱(PC)含量大豆粉末磷脂为原料,建立以碱性乙醇为溶剂结合冷冻纯化制备高纯度磷脂酰肌醇(PI)的方法。在单因素实验的基础上利用响应面优化实验确定PI的最佳提取条件为:冷冻时间17 h,冷冻温度-20℃,提取温度40℃,料液比1∶27,98%乙醇与25%氨水体积比100∶4,提取时间40 min,提取次数3次。在最佳条件下,产物PI含量为82.62%,得率为14.29%。     

生物柴油副产物甘油中磷脂酰胆碱的提限纯化研究

以生物柴油副产物甘油中分离得到的粗磷脂为原料,采用乙醇提取、减压蒸馏浓缩制备较高纯度磷脂酰胆碱(PC).通过响应曲面设计考察了料液比、提取温度、提取时间、搅拌速度对提取率的影响.优化的最佳提取条件为:液料比42:1(mL/g),提取温度46℃,提取时间38min,搅拌速度328r/min,提取一次.经实验验证,提取率达到78.2%,Pc含量由原来的46%提高到77%.     

大豆磷脂酰肌醇的提取工艺研究

为探究溶剂分提法提取较高纯度的磷脂酰肌醇(PI),以提取PC后的大豆粉末磷脂为原料,在单因素实验的基础上,进行响应面优化实验,以PI含量为指标,确定了以碱性乙醇为溶剂提取磷脂酰肌醇的最佳工艺条件:温度为40℃、液料比为20∶1、碱性乙醇氨水浓度为2.60mL 25%氨水/100mL无水乙醇、时间50min、提取两次。在此条件下,磷脂酰肌醇的纯度为58.86%,得率为70.14%。     

大豆磷脂酰乙醇胺的分离及纯化

以提取卵磷脂(PC)后的大豆粉末磷脂为原料,以碱性乙醇为溶剂提取磷脂酰乙醇胺(PE),并进行冷冻纯化。在单因素实验的基础上,以PE得率为指标,响应面优化实验确定了PE的最佳提取条件为:提取温度45℃,料液比1∶20,乙醇碱浓度V(无水乙醇)∶V(25%氨水)=100∶2,提取时间50 min,提取次数2次。在最佳条件下,PE得率为79.53%,含量为48.42%;当冷冻温度为-15℃,冷冻时间为8 h时,PE含量提升到72.73%,得率为66.71%。     

蛋黄磷脂的制备及脱色工艺的研究

蛋黄磷脂的纯度、提取率和色泽是评价提取效果的关键指标,为得到色泽浅,提取率、磷脂含量高的产品.本试验以磷脂蛋白粉为原料,采用乙醇为溶剂,中性活性炭为脱色剂制备蛋黄磷脂.确定了乙醇提取蛋黄磷脂的较优条件,并对活性炭脱色试验进行优化.试验结果表明,在乙醇浓度为95%,物料与乙醇比为1:7(w/v),提取时间为40 min,提取温度30℃条件下,可以得到提取率及纯度较高的蛋黄磷脂.利用活性炭脱色,结果表明,在活性炭添加量为4%,脱色时间60 min,脱色温度45℃的条件下,脱色率达到96.47%,得到提取率为23.48%,磷脂含量为95.26%的淡黄色蛋黄磷脂.通过此技术,可制得色泽好,提取率和纯度较高的优质蛋黄磷脂.     

丙酮萃取蛋黄磷脂工艺研究

研究了以磷脂酰胆碱萃取率为指标,利用正交试验优化丙酮萃取蛋黄磷脂工艺中料液比、萃取温度、萃取时间等参数,并考察了超声对磷脂酰胆碱萃取率的影响。得到最佳萃取条件:不超声,萃取温度20℃,料液比1∶7,萃取时间70 min。在最佳条件下,PC萃取率可达96.955%。     

浓缩大豆磷脂的溶剂分提

浓缩大豆磷脂为磷脂混合物，并含有中性脂、糖酯、碳水化合物及非磷酯等物质。为了提高磷脂产品中磷脂酰胆碱的含量，试验以浓度大豆磷脂为原料，使用乙醇作溶剂，制备富磷胆酰胆碱产品，最佳工艺条件是：35℃，90%乙醇、萃取时间30min.     

南美白对虾虾头中磷脂提取工艺的优化

以南美白对虾虾头为原料,研究利用正己烷-异丙醇混合溶剂提取虾头中的磷脂。以磷脂相对提取率为评价指标,在单因素试验的基础上进行正交试验,确定优化提取工艺条件为:正己烷与异丙醇的混合比为3:1(V/V)、料液比l:8(g/mL)、提取时间2h、提取温度40℃,此条件下与经典氯仿-甲醇法比较,相对提取率达98.11%。磷脂丙酮不溶物含量为85.4%,乙醚不溶物含量为0.2%,两项指标均高于一级浓缩磷脂的标准。通过薄层色谱分离定性,共有5种磷脂,其中4种分别为磷脂酰乙醇胺、磷脂酰胆碱、神经鞘磷脂和磷脂酰丝氨酸,剩余一种尚未确证。正己烷-异丙醇提取法安全、有效,为充分利用虾头等废弃物资源,从中提取磷脂提供了新的方法。     

乙醇冷冻法纯化分离大豆磷脂酰胆碱研究

以大豆粉末磷脂为原料,结合乙醇萃取和乙醇冷冻纯化两个步骤提取纯化磷脂酰胆碱;重点探讨乙醇冷冻纯化步骤工艺条件,考察冷冻时间、冷冻温度、料液比、乙醇浓度等因素对乙醇冷冻纯化效果影响,并在单因素试验基础上进行正交试验,确定最佳冷冻纯化工艺为:冷冻时间6h,冷冻温度-12℃,料液比1:8,乙醇浓度97.5%,在此条件下纯化分离,磷酯酰胆碱含量由45.8%提高至70.5%、得率为81.2%。     

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