响应面法优化微波辅助提取枣皮红色素

采用响应面法优化微波辅助提取枣皮中红色素的条件。在单因素试验基础上,选择微波时间、微波功率和NaOH浓度为提取因子,进行三因素三水平Box-Behnken中心组合设计,采用响应面法分析优化提取工艺。结果表明:微波辅助提取枣皮中红色素的最优条件为微波功率540W,微波时间134s,NaOH浓度0.51mol/L,料液比1∶10,在此条件下,模型预测值为1.830,验证实验值为1.815,说明模型具有良好的拟合度,能够较好地描述试验结果。     

响应面优化微波辅助提取甜菜红色素及其稳定性研究

通过单因素试验对甜菜红色素提取条件(料液比、温度、提取时间、提取液p H、提取溶剂等)进行初步探究,并通过微波辅助对色素提取进行响应面优化设计,结果表明影响提取最显著的因素是微波时间,其次是微波功率,最后是料液比。最适提取条件:料液比1∶5.76(g/m L),微波功率398 W,微波时间112.8 s,此条件甜菜红色素最大吸光度值为0.711 4。对提取的甜菜红色素进行超滤处理并对其粗提液进行稳定性研究,结果表明光照、p H对其稳定性影响显著,添加不同稳定剂对甜菜红色素稳定性有一定改善,苯甲酸钠(0.04%)和VC(0.04%)复配使用对于提高其稳定性作用较为明显。     

超声波辅助浸提甜菜红色素的工艺研究

利用超声辅助乙醇浸提法萃取技术,优化甜菜中红色素提取工艺参数。以单因素试验为基础,采用正交实验优化提取甜菜红色素工艺,确定最佳提取条件为:浸提液乙醇浓度40%,pH值5.5,料液比1∶10,超声波功率90%W(占总功率),提取温度40℃,提取时间40 min。     

微波法提取鹿角漆树果穗红色素的工艺研究

采用微波法提取鹿角漆树果穗红色素,采用单因素试验法和正交试验法考察了提取剂的类型、pH值、料液比、微波功率、提取时间5个因素对鹿角漆树果穗红色素提取的影响。试验结果表明:最佳提取溶剂为50%乙醇。微波提取鹿角漆树果穗红色素的各因素影响顺序依次为:微波功率pH值提取时间料液比;优化工艺条件为提取时间5min,微波功率为320W,pH值为5,料液比为1:30。     

响应面法优化微波提取阳荷水溶性膳食纤维工艺

研究野生阳荷水溶性膳食纤维的最佳提取工艺,以提取时间、料液比、微波功率和浸提液pH值为影响因素,进行四因素三水平的响应面试验设计,对其提取工艺条件进行优化,结果表明：最佳提取工艺条件为提取时间151.4 s、料液比1∶33（g/mL）、微波功率264 W、浸提液pH 3.65,此条件下水溶性膳食纤维的提取率为5.52%,与理论值5.75%相差较小。由此可知,响应面法优化微波辅助提取阳荷水溶性膳食纤维具有时间短、能耗低、提取率高等特点。     

响应面法优化微波提取玫瑰茄花色苷工艺研究

采用响应面法优化微波提取玫瑰茄花色苷工艺,在单因素实验基础上,以微波功率、料液比、提取时间为自变量,设计三因素三水平响应面实验,以花色苷含量为响应值进行响应面优化。结果表明,影响花色苷提取效果的3个因素其影响大小依次为料液比微波功率提取时间,最佳工艺条件为微波功率164 W,料液比1:25,提取时间12 min,利用此工艺参数得到的花色苷含量为537.873 mg/100 g。     

响应面法优化微波提取桑叶黄酮和多糖工艺研究

采用微波提取法提取桑叶黄酮和多糖,并用响应面法优化提取工艺。在讨论料液比值、微波功率、微波时间的单因素水平上,根据Box-Behnken试验设计原理,通过响应面分析得到优化组合条件。根据实际试验条件得到最优提取工艺条件为料液比值90 m L/g、微波功率400 W、微波时间15 min。桑叶黄酮和多糖提取率预测值分别是9.94%和4.01%,实际测量值分别是9.84%和3.91%,相对误差分别为1%和2.5%。     

响应面法优化微波辅助提取红皮云杉多酚工艺

采用响应面法优化微波辅助提取红皮云杉多酚工艺。在单因素实验的基础上,选择料液比、微波功率、提取时间为自变量,以多酚得率为响应值,采用Box-Benhnken法设计三因素三水平的响应分析实验。结果表明,回归模型拟合度高,最佳工艺条件为:料液比1∶31(g/mL)、微波功率295W、提取时间46s,乙醇浓度40%。在此条件下,红皮云杉多酚得率的预测值为17.51%,实际值为17.38%,两者相对误差<1%,表明该工艺条件合理可行。     

响应面优化微波辅助提取海鲜菇废菌棒中多糖工艺

采用微波辅助提取工艺从海鲜菇废菌棒中提取多糖,通过控制提取时间、微波功率以及液料比3个提取条件来优化提取工艺。在单因素试验基础上,结合响应面法,得出优化后的提取参数:提取时间10 min,微波功率420 W,液料比31∶1(mL/g)。在此条件下海鲜菇废菌棒多糖的提取效果最佳,提取率为2.01%。     

响应面法优化微波提取生姜多糖的工艺

利用响应面法优化微波提取生姜中多糖的工艺条件。在单因素试验的基础上,选取料液比、浸泡时间、微波时间和微波功率为影响因子,应用Box-behnken中心组合设计建立数学模型,以多糖的提取率为响应值,进行响应面分析。微波提取生姜中多糖的最佳工艺条件为料液比1∶22.21(g/m L),浸泡时间为120.06 min,微波时间为86.43 s,微波功率为247.02 W。此条件下多糖的提取率预测值为18.91%,验证值为18.93%。     

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