超临界CO_2流体萃取核桃油研究

本文研究应用超临界CO2流体萃取技术提取核桃油工艺。采用四因素三水平正交试验,考 察压力、温度、萃取时间、CO2流量四因素对核桃油萃取率影响效果。最佳萃取条件为:压 力30 Mpa,温度50℃,时间4h,CO2流量25kg/h,在此条件下萃取率可达52.4％。利用 GC/MS分析核桃油成分组成,比较超临界CO2萃取油样和乙醚萃取油样的理化性质。     

超临界CO2萃取核桃油的研究

研究了影响核桃油超临界CO2流体萃取的因素,在试验条件下,其影响因素次序为:夹带剂、萃取压力、CO2体积,萃取温度影响不大.优化了超临界CO2流体萃取核桃油的工艺条件:夹带剂无水乙醇,用量为投料量的质量分数的10%;萃取压力30 MPa,萃取温度35℃,萃取时间3.5 h,CO2流量15～20kg/h.用气相色谱法分析了超临界CO2流体萃取核桃油的脂肪酸酸组成和含量,其不饱和脂肪酸含量较高.     

核桃油的超临界CO2流体萃取及其脂肪酸成分分析

采用超临界CO2流体萃取技术对核桃仁中核桃油的提取进行了研究。通过单因素试验,考察了萃取压力、温度、时间以及CO2流量对核桃油萃取率的影响。在单因素试验的基础上,用正交试验进行了工艺参数优化,其最佳萃取条件为:压力30 MPa、温度45℃、时间3 h、CO2流量4 L/min,在此条件下萃取率达到了50.1%。最后,通过气相色谱仪测定了核桃油的脂肪酸组成成分,结果表明,不饱和脂肪酸的质量分数92.2%,其中油酸、亚油酸和亚麻酸的质量分数分别为36.1%、14.2%和1.4%。     

南瓜子油的超临界CO_2流体萃取研究

应用超临界CO2 萃取技术 ,研究了南瓜子油的提取工艺 ,着重探讨了原料预处理、萃取压力、温度、萃取时间、CO2 流量对油脂萃取率的影响 ,优化了工艺条件 :压力 3 0MPa ,温度 45℃ ,时间 2 .5h ,CO2 流量 2 5kg/h。利用GC/MS分析了南瓜子油的成分组成 ,比较了超临界CO2 萃取的油样和乙醚萃取油样的理化性质。     

超临界CO2和微波萃取核桃油的比较研究

通过超临界CO2萃取核桃油的正交实验和微波萃取核桃油的均匀设计实验,考察影响核桃油萃取的主要因素,寻求最佳萃取工艺条件.研究结果表明,超临界CO2萃取的最佳工艺条件为:萃取压力35 MPa,萃取温度45℃,萃取时间2.5 h,分离温度50℃,CO2流量25 kg/h;在此条件下油脂得率为59.2%.微波萃取最佳工艺条件为:以环己烷为萃取剂,溶料比为3.5:1(W/W),微波功率735 W,每次微波辐射时间60 s,微波辐射累计时间6 min,在此条件下得率为60.4%.比较了不同提取方法对油脂得率和油脂品质的影响.结果表明,微波萃取油脂得率最高,时间最短;超临界CO2萃取的核桃油品质最优,是萃取优质核桃油的首选方法.     

马尾藻的超临界CO2脱脂工艺研究

研究了超临界CO2萃取压力、萃取温度、萃取时间对马尾藻脱脂过程的影响。结果表明,CO2的流量为20L/h时,超临界CO2脱脂的最佳工艺条件为:萃取压力45MPa,萃取温度55℃,时间4h,萃取率为8.07‰。     

玉米胚芽油的超临界CO2萃取

研究了超临界CO2流体萃取玉米胚芽油的条件,着重研究了萃取压力、温度、萃取时间和CO2流量对油脂萃取率的影响,优化了萃取工艺条件;萃取压力35MPa,温度50℃,时间3h,CO3流量34kg/h,并利用GC／MS分析了最佳条件下萃取的玉米胚芽油成分组成。并比较了超临界CO2萃取的玉米胚芽油样和乙醚萃取油样的理化性质。     

超临界CO2萃取红曲色素的研究

对用超临界CO2萃取红曲米中红曲色素进行了初步研究，考察了压力、温度、CO2流量及原料颗粒直径对萃取效果的影响。通过试验得到较佳的操作条件为：红曲米原料颗粒Ф0．3mm，萃取温度50℃，萃取压力20MPa，CO2流量10kg／h，萃取时间4h。     

碱蓬籽油的超临界CO2流体萃取及其GC/MS分析

应用超临界CO2萃取技术，研究了碱蓬籽油的提取工艺，采用四因素三水平正交试验，考察了压力，温度，萃取时间、CO2流量四因素对碱蓬籽油萃取率的影响，研究得出最佳萃取条件为：压力25MPa，温度42．5℃，时间3h，CO2流量25kg/h。利用GC／MS分析了碱蓬籽油的组成成分，比较了超临界CO2萃取油样和乙醚萃取油样的理化性质。     

超临界CO2流体萃取茶籽油的研究

茶籽油是一种很受欢迎的食用油,具有极高的营养和保健价值。本文探讨了超临界CO2萃取的压力、温度、流量、时间等因素对茶油萃取率的影响,确定了其最佳萃取条件：萃取压力35MPa、温度50℃、CO2流量20kg／h、萃取时间150min,萃取率为33．5％。有机溶剂萃取法的萃取率为30．3％,结果表明超临界CO2萃取的萃取率高,萃取时间短,无溶剂残留。     

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