水洗法去除蓖麻饼粕中蓖麻碱工艺优化

采用响应面法优化蓖麻饼粕中蓖麻碱的去除工艺,以蓖麻碱去除率为考察指标,在单因素基础上,选取料液比、处理温度及处理时间三个因素进行中心组合实验,通过响应面分析法对处理温度、处理时间及料液比进行优化,得到蓖麻碱去除工艺的最佳料液比为1∶7,最佳处理温度80℃,最佳处理时间6h,此时蓖麻碱的去除率为84.12％.     

蓖麻粕中蓖麻碱的微波辅助提取工艺优化及其抑菌性

以蓖麻粕为原料,以水为提取溶剂,在单因素试验的基础上通过响应面法优化了蓖麻碱的微波辅助提取工艺,并通过滤纸片法初步研究了蓖麻碱的抑菌性。微波辅助提取蓖麻碱的最佳工艺条件为:微波功率408.01 W,提取时间5.21 min,液固比12∶1(mL∶g),在此条件下蓖麻碱的提取率预测值为50.74%,验证实验中蓖麻碱提取率为50.81%,相对偏差为0.14%。蓖麻碱的抑菌性结果表明蓖麻碱对供试菌都具有抑菌作用,对各种菌的抑制效果为:大肠杆菌>淀粉液化芽孢杆菌>金黄色葡萄球菌。     

滩涂植物碱蓬籽中总酚的提取工艺优化

以盐城滩涂湿地物种碱蓬为原料,乙醇为提取溶剂,选用超声辅助的提取方法研究碱蓬籽中的总酚提取工艺并对工艺进行优化。在单因素实验的基础上,确定提取温度、提取时间、料液比及乙醇的体积分数四个主要因素,研究对响应值总酚的提取量。采用响应面分析法中的Box-Behnken Design中心组合法设计实验工艺,通过方差分析确定回归模型及分析各因素的交互作用。优化的最佳工艺条件为:以80%乙醇溶液为提取剂,提取时间为80min,提取温度为80℃,料液比为23g/m L,此时理论预测提取量为996.94μg/g。在此条件下进行三次平行验证实验测得碱蓬籽中的总酚提取率为986.03μg/g,RSD%为1.41,说明实验得到的回归模型用来研究碱蓬中的总酚含量是准确的和科学的,具有一定的参考价值。     

响应面优化碱提棉籽蛋白的工艺条件

采用先酸洗除杂再碱提和响应面设计法优化棉籽蛋白提取工艺。用单因素试验考察了碱提棉籽蛋白的工艺参数,采用响应面分析法对pH、提取温度和提取时间等主要工艺参数进行了优化,优化后最佳提取工艺条件为:pH=11.57、提取温度60.59℃、提取时间2.03 h,在此条件下棉籽蛋白提取率为80.22%,蛋白纯度90.63%。经平行试验,在最佳工艺条件下,棉籽蛋白平均提取率为80.37%,试验结果与响应面优化预测结果较吻合,说明响应面优化得到的工艺条件准确可靠。     

响应面法优化红小豆豆渣中蛋白的提取工艺

采用碱溶酸沉的方法对红小豆豆渣中的蛋白进行提取。通过单因素实验考察了pH、提取温度、提取时间、料液比对蛋白提取率的影响,并通过响应面实验对蛋白的提取条件进行了优化。结果表明:在最佳提取条件下,即pH10.0、提取温度60℃、提取时间100min、料液比1∶18进行提取,提取率可达62.99%,蛋白质的纯度为93.25%。     

大豆异黄酮、大豆皂甙的提取工艺研究

通过溶剂对比实验及单因素实验确定了从大豆粕中提取大豆异黄酮和大豆皂甙的最佳提取溶剂及影响浸提效果的相关因素，并通过响应面实验优化了最佳工艺条件：温度70℃、乙酸浓度72.4%、每次提取液料比为10.3∶1、每次提取时间3.5h，提取2次。该条件下大豆异黄酮提取率为0.507%、皂甙为5.48%。     

仙草多糖提取工艺的优化

目的对仙草多糖碱液提取工艺条件进行优化。方法研究碱提法提取仙草多糖的条件,考察碱浓度、提取温度、提取时间及液料比等因素对仙草多糖得率的影响。在单因素实验的基础上,选取碱浓度、提取时间及液料比3因素应用响应面中Box-Benhnken设计原理进行试验设计,以仙草多糖提取率为响应值,建立多糖提取率的二次回归方程,得到碱液提取多糖的最佳条件。结果仙草多糖提取的最佳浸提条件:Na HCO_3 1.25%,提取时间3h,液料比35:1(V:m),在此条件下仙草多糖提取率为8.10%。结论碱液提取法能够提高仙草多糖的提取率。     

响应面法优化牛大力碱溶性多糖的提取工艺

以牛大力为原料提取碱溶性多糖,比较NaOH浓度、浸提温度、浸提时间、液料比以及提取次数对碱溶性多糖提取率的影响,并以NaOH浓度、温度、时间、液料比为考察因素,基于单因素试验结果,采用RSA响应面分析法优化提取工艺。结果表明,液料比对牛大力碱溶性多糖提取率影响最大,其次是浸提时间和NaOH浓度,浸提温度对牛大力碱溶性多糖提取率影响最小。确定碱溶性多糖提取的最佳工艺参数,即NaOH浓度5.2%、温度61℃、时间2.3 h、液料比34∶1 (mL/g)。在此优化工艺下碱溶性多糖提取率为15.91%,与响应面预测值15.76%拟合良好。     

响应面法优化离子液体双水相提取银杏黄酮的工艺研究

通过合理的实验设计和响应面优化获得一种提取银杏黄酮的最佳工艺条件。采用离子液体[C4mim]Br与(NH_4)_2SO_4形成的双水相体系提取银杏黄酮,通过离子液体用量、盐用量、样品加入量、pH、温度和时间六个影响因素进行单因素分析,依据Design-Expert 8.0.6软件Box-Benhnken试验设计原理设计实验,以离子液体量、盐用量、体系温度为三个独立变量,以总黄酮提取效率为响应值进行方差分析并进行多项式拟合回归建立多元二次响应面回归模型,确定各影响因素对黄酮提取率的主次性为:IL量硫酸铵量体系温度,在[C4mim]Br/(NH_4)_2SO_4双水相提取中,各个因素的最佳条件组合为:离子液体质量分数为35.09%,硫酸铵质量分数为27.94%,样品加入量0.11g,体系温度50.22℃,pH为6,提取时间45min,在优化后的条件下进行实验,银杏叶黄酮的预测提取率可以达到1.65%。在优化后的提取条件下进行黄酮提取,做3次平行实验所得到的黄酮提取率为1.63%,与预测值相比较,误差为1.21%,说明此模型优化的提取条件准确可靠。     

响应面法优化亚临界水提取槟榔籽中槟榔碱的 工艺研究

目的利用响应面试验优化亚临界水提取槟榔籽中槟榔碱的工艺。方法在单因素实验的基础上,利用单因素试验结合Box-Benhnken实验和响应面分析法,研究提取温度、提取时间以及液料比3个因子对槟榔籽槟榔碱提取率的影响,通过回归分析模拟得到二次多项式回归方程的预测模型。结果亚临界水提取槟榔籽中槟榔碱的最佳工艺条件为提取温度144℃,提取时间43 min,液料比35:1(mL/g)。由模型预测提取率为4.23mg/g,验证实验结果为4.25 mg/g,误差仅为0.47%,与预测值较接近,表明模型具有较好预测性。且各因子对提取率的影响大小依次是提取温度提取时间液料比。结论亚临界水提取可以作为一种有效的槟榔籽中槟榔碱提取方法。     

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