超临界CO2提取与分离花椒油树脂的研究

花椒是我国特有的、资源丰富的一种调味品和中药原料,对其精深加工具有重要的现实意义.通过单因素和正交实验确定了超临界CO2萃取花椒油树脂的最佳工艺条件为原料粒度40目,萃取时间2 h,流量25 kg/h,温度45℃,压力32 MPa,油树脂得率12.63%.采用超临界CO2分离花椒油树脂中挥发油的适宜工艺条件为分离器Ⅰ的分离压力12MPa,温度40℃.分离器Ⅰ花椒油树脂得率为1.2%,其中挥发油含量为15.7%.实验结果表明,采用此工艺可有效地提取与分离花椒油树脂.     

花椒麻味成分的提取与分离技术

花椒是我国特有的、资源丰富的一种调味品和中药原料 ,辛麻味是其主要的风味特征。文中通过单因素和正交试验确定了超临界CO2 萃取花椒麻味成分的最佳工艺条件为 :原料粒度 60目 ,萃取时间 2h ,流量 2 1kg/h ,温度 5 5℃ ,压力 3 6MPa,油树脂得率达 1 2 83 %。采用超临界CO2分离花椒油树脂中麻味成分的适宜工艺条件为 :分离器Ⅰ分离压力 1 2MPa,温度 40℃。分离器Ⅰ花椒油树脂得率为 1 85 % ,其中挥发油含量为 60 0 2 8mg/g。试验结果表明 ,采用此工艺可对花椒麻味成分进行有效地提取与分离     

响应面法优化超临界CO2萃取花椒油的工艺

研究超临界CO2萃取花椒油的最优工艺条件。通过单因素实验考察了萃取温度、萃取压力和萃取时间对花椒油萃取率的影响,采用响应面法进行优化。结果表明:花椒油最优萃取工艺条件为萃取温度42℃、萃取压力19. 8 MPa、萃取时间90 min,在此条件下花椒油平均萃取率为16%。     

超临界CO2萃取花椒油的工艺研究

本文研究了超临界CO2萃取花椒油的工艺，探讨了萃取压力、温度、时间对萃取率的影响。通过正交试验得到最佳萃取工艺条件为：萃取压力20MPa、萃取温度46℃、萃取时间6h。     

超临界萃取花椒中主要成分

采用超临界流体萃取技术萃取花椒油脂,通过单因素试验和正交试验设计,研究花椒粉粒度、萃取压力、萃取时间和萃取温度等因素对花椒油脂的萃取率的影响,找到最佳的工艺条件。研究结果表明最佳工艺参数为花椒粉粒度60目、萃取压力15 MPa、萃取时间1.5 h、萃取温度45℃、CO2流量5 L/h~10 L/h。在此条件下,花椒油脂的萃取率可达12.27%以上。影响提取率的主次因素为萃取温度萃取压力萃取时间。     

花椒油萃取回流工艺的研究

采用正交实验法方法研究不同工艺条件萃取回流法对花椒油的提取工艺的影响，得出最佳浸提工艺及相关工艺参数。试验结果证明采用溶剂用量1：3（g／mL），萃取时间（32h），回流温度（55～60℃），回流时间（1．5h）的工艺进行花椒油的萃取效果最好，并且具有操作简单、提取时间短、纯度高、得率高、无需加热，剩余物无有害残留，可以综合利用的优点。     

花椒麻辣调味汁的工艺研究

利用超临界CO2萃取的花椒油树脂制备了麻辣调味汁。麻辣调味汁配方为：花椒油树脂1．6％，盐10％，糖1．5％，味精0．5％，吐温（80）0．25％。料液温度50-60℃，压力25MPa均质2次，可获得稳定性良好的花椒麻辣调味汁。     

紫外分光光度计法测花椒油中酰胺类物质含量

花椒油中酰胺类物质的含量是影响花椒油质量的重要因素。研究了应用分光光度计法测定花椒酰胺类物质的最适条件。结果表明：应用甲醇萃取花椒油中的酰胺类物质，在萃取时间为4h，萃取温度为40℃，萃取液3h内测定时，具有良好的回收率和重复性。     

超临界CO2萃取芫荽油树脂工艺研究

通过单因素实验和3因素4水平正交实验考察了超临界二氧化碳萃取中萃取压力、萃取温度、CO2流量对芫荽油树脂萃取率的影响,结果表明各影响因素的影响顺序为萃取温度＞萃取压力＞CO2流量.在萃取时间为3h时,得出萃取的最佳工艺条件为萃取压力18MPa、萃取温度43℃、CO2流量35L/h,此条件下芫荽油树脂的萃取率达到1.035%.     

超临界CO_2流体萃取假蒟油树脂的工艺研究

采用超临界CO_2流体萃取技术,以假蒟(地上茎叶部分)为原料,对超临界CO_2萃取假蒟油树脂的工艺进行研究。通过单因素试验,探讨萃取时间、萃取压力以及萃取温度对假蒟油树脂提取率的影响,并采用正交试验优化超临界CO_2萃取假蒟油树脂的工艺条件。结果表明,超临界CO_2流体萃取假蒟油树脂的最佳工艺条件为:萃取时间1.5 h、萃取压力20MPa、萃取温度55℃。在此条件下,对假蒟油树脂进行超临界CO_2提取,提取率高达4.19%。     

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