响应面分析法优化白籽仁多糖提取工艺的研究

以白籽仁为原料,以水为提取溶剂,采用冷凝回流提取的方法,通过单因素实验和响应面实验研究白籽仁多糖的最佳提取工艺,考察了提取温度、提取时间、液料比和提取次数对白籽仁多糖提取得率的影响,确定最佳提取条件为:提取温度93℃,提取时间1.7 h,液料比180m L/g,提取次数为2次,在此条件下,多糖最高提取得率为57.54%。     

油菜花粉多糖提取工艺条件研究

对油菜花粉多糖的提取工艺进行研究。探讨浸提次数、时间、料液比和温度对多糖得率的影响,在单因素试验的基础上,通过正交试验确定最佳提取工艺条件。结果表明:温度对多糖得率的影响最大,其次为提取时间、次数,料液比的影响最小。油菜花粉多糖提取的最优条件为1:4的料液比,90℃水浴条件下,浸提4次,每次浸提4h,其水溶性多糖提取率达1.450%。     

绿茶中提取茶多糖最佳工艺的优化

采用单因素实验和L9(34)正交实验对绿茶中茶多糖的提取工艺进行了研究,研究了料水质量比、浸提温度、浸提时间、浸提次数对茶多糖提取的影响。结果表明,影响茶多糖得率的主次因素为:料水质量比、浸提温度、浸提次数、浸提时间;最佳提取工艺条件为:料水质量比为1∶25,提取温度85℃,提取时间为90min,提取1次。在此最佳工艺条件下,茶多糖得率为1.92%。      

绿茶中提取茶多糖最佳工艺的优化

采用单因素实验和L9(34)正交实验对绿茶中茶多糖的提取工艺进行了研究,研究了料水质量比、浸提温度、浸提时间、浸提次数对茶多糖提取的影响。结果表明,影响茶多糖得率的主次因素为:料水质量比、浸提温度、浸提次数、浸提时间;最佳提取工艺条件为:料水质量比为1∶25,提取温度85℃,提取时间为90min,提取1次。在此最佳工艺条件下,茶多糖得率为1.92%。     

玫瑰花渣中多糖的提取研究

通过单因素实验和L9（34）正交实验,研究提取时间、提取温度、提取次数和料液比对多糖得率的影响。利用Sevage法脱蛋白,高浓度乙醇反复洗涤法除色素,得到玫瑰多糖。并用苯酚-硫酸法测定多糖纯度。结果表明:提取时间和提取温度是影响玫瑰多糖提取的主要因素,最佳工艺方案为:提取时间5h,提取温度100℃,提取次数2次,料液比1:30,在此工艺条件下,玫瑰多糖的得率为0.6%。经脱蛋白和脱色后,多糖纯度为89.5%。      

超声法提取猴头菇多糖工艺优化研究

目的:考察超声法提取猴头菇多糖的影响因素,并优化提取工艺。方法:以猴头菇多糖提取率为评价指标,用苯酚-硫酸法测定多糖含量,在单因素实验基础上,以超声提取时间、超声提取温度和料液比为实验因素,通过正交实验筛选最佳提取工艺条件。结果:影响猴头菇多糖提取率的因素依次为提取温度提取时间料液比;最佳工艺条件为提取时间20min,提取温度60℃,料液比1∶15 (g/mL),在此条件下猴头菇多糖得率为6.16%。结论:该工艺方便可行。     

响应面法优化去皮绿豆多糖提取工艺技术的研究

以去皮绿豆为主要原料,通过单因素实验,探讨了提取温度、提取时间、料液比、提取次数等因素对绿豆多糖得率的影响。并且在单因素结果的基础上,利用响应面分析法优化提取绿豆多糖的最佳工艺条件。实验结果表明,水提醇沉法提取去皮绿豆多糖的最佳工艺参数为:提取温度95.5℃,提取时间3h,料液比为21∶1,提取1次,在此条件下去皮绿豆中可溶性粗多糖的得率可以达到4.32%。经Sevag法脱蛋白后,其中多糖纯度为50.35%,蛋白含量为31.26%。      

毛酸浆果实多糖的提取

采用水提醇沉法从毛酸浆果实中提取多糖,选择提取温度、提取时间、料液比和提取次数作为单因素进行实验,再通过L9(34)正交实验确定最佳提取条件,得到毛酸浆多糖提取最佳条件为提取温度100℃,时间3h,料液比1:20.在最佳提取工艺条件下,毛酸浆多糖得率为5.38%.     

鹿角灵芝粗粉和超微粉多糖提取工艺的比较研究

以鹿角灵芝粗粉和超微粉为材料,采用热水提取其中的灵芝多糖,通过单因素和正交试验研究提取温度、提取时间和料液比对多糖提取效果的影响,确定鹿角灵芝粗粉和超微粉提取多糖的最佳工艺条件。结果表明,鹿角灵芝粗粉水提多糖的最佳工艺条件为温度90℃、时间2h、料液比1:30,多糖提取率为0.63%;鹿角灵芝超微粉水提多糖的最佳工艺条件为温度90℃、时间1h、料液比1:30,多糖提取率为1.93%;鹿角灵芝超微粉水提多糖的得率是粗粉水提多糖得率的3倍。     

桑黄菌丝体多糖的提取及其抗氧化活性研究

研究了桑黄(Phellinus igniarius)菌丝体多糖热水提取的最佳工艺条件及其体外抗氧化活性。通过单因素实验和正交实验对提取工艺进行优化,考察提取时间、温度和料液比及提取次数对桑黄菌丝体多糖得率的影响。最佳提取工艺条件为温度100℃,时间2 h,料液比1∶15 g/m L,提取2次。在该条件下,桑黄菌丝体多糖得率为6.64%。该粗多糖含量为69.29%,蛋白含量为3.20%。浓度为0.2 mg/m L的桑黄菌丝体多糖对超氧负离子清除率为49.4%,对羟基自由基的清除率为28.7%,还原力为0.072,低于V_C相对应的抗氧化能力。     

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