玉米朊的活性炭脱色工艺研究

系统研究了玉米朊的活性炭脱色工艺。以活性炭为脱色剂,对玉米朊的乙醇溶液进行脱色,并对影响活性炭脱色效果的因素进行了考察,对脱色的工艺条件进行了优化。结果表明:脱色的最佳工艺条件是温度50℃、活性炭与玉米朊的乙醇溶液的固液比2.5%(g/mL)、脱色时间为2h、乙醇浓度为90%、pH值为7,此时玉米朊乙醇溶液的吸光度为0.460;影响脱色效果的因素的主次顺序为乙醇溶液浓度>料液比>pH值>脱色时间。活性炭可用于玉米朊的脱色。     

发酵液中L-异亮氨酸提取工艺研究

为了从发酵液中高效的提取L-异亮氨酸,文本对发酵液中L-异亮氨酸的分离提取工艺作了初步研究。分别考察了蛋白去除温度及时间、活性炭用量、脱色时间、脱色温度、发酵液pH值对L-异亮氨酸分离提取效果的影响。最终确定了提取的工艺条件,即蛋白去除温度及时间分别为90℃和10min、活性炭添加量为2％、脱色温度为60℃、脱色时间为25min、脱色时的最佳pH为4．7。在此工艺条件下,L-异亮氨酸提取收率为94．3％,产品纯度高达96．5％。     

L-缬氨酸发酵液脱色工艺的研究

本文探讨了活性炭对经金属膜分离得到的L-缬氨酸（L-γa1）发酵液脱色效果的影响,并考察了脱色过程中主要影响因素。以活性炭用量、发酵液pH、脱色温度、脱色时间为考察因素,色素去除率和L-缬氨酸回收率为考察指标,采用正交试验法对脱色工艺进行优化,确立了最佳的工艺条件为：活性炭用量2%,脱色料液pH5.4,脱色温度50℃,脱色时间20min,料液浓度35g/L~60g/L。     

梅花鹿胎盘水解液脱色效果的研究

梅花鹿胎盘酶解液有较重的色素。试验采用活性炭对鹿胎盘酶解液进行脱色,研究了不同pH值、活性炭用量、温度、脱色时间下活性炭对鹿胎盘酶解液的脱色效果的影响。由正交试验得出最佳工艺条件为pH值3.0、活性炭用量为2%、温度为40℃、脱色时间为100min,在此条件下鹿胎盘酶解液脱色率为87.77%,蛋白质损失率为40.23%。     

红松松塔多糖活性炭法脱色工艺的研究

摸索红松松塔粗多糖脱色工艺条件,为松塔粗多糖的纯化提供理论依据.实验采用活性炭法对红松松塔多糖进行脱色研究,利用单因素和正交试验研究了活性炭浓度、脱色温度、脱色时间和pH值对松塔粗多糖脱色工艺的影响.研究结果,表明活性炭法最佳脱色工艺条件为活性炭浓度1.5％、时间60min、温度50℃和pH值3.本研究为红松松塔多糖的进一步纯化提供了科学依据,为松塔的开发利用奠定理论基础.     

营养性双糖——麦芽糖脱色工艺优化

麦芽糖是一种营养性双糖,采用粉末活性炭为脱色剂,以麦芽糖液的脱色率为考察指标,对其脱色工艺进行了研究,通过单因素实验和正交实验对麦芽糖脱色条件进行了优化,确定最佳的脱色工艺条件是活性炭用量2.5%(m/m)、脱色温度80℃、脱色时间20 min、pH值3.6,此时活性炭对麦芽糖液的脱色率为85.98%.     

甜菊糖溶液活性炭脱色工艺研究

为解决甜菊糖产品的颜色问题,选用活性炭对甜菊糖苷溶液进行脱色,并对甜菊糖溶液的脱色率和甜菊糖的损失率进行研究。先通过单因素试验初步确定活性炭的添加条件及添加量,在脱色效果达到的情况下针对甜菊糖的损失率进行正交试验,对活性炭添加比例、溶液温度、吸附时间、pH值对溶液脱色率和甜菊糖损失率的影响进行试验,证明各种因素对脱色效果和甜菊糖损失的影响不同,活性炭的添加比例影响因素最大,其次是时间,再次是温度,影响最小的是pH值。单因素试验和正交试验确定最佳工艺条件为:最佳活性炭添加比例为1%,最佳温度10℃,最佳时间为0.5h,最佳pH值为7.0,产品吸光值达到标准要求,甜菊糖损失率为2.72%。     

香菇多糖脱色方法的研究

从香菇菌丝体中提取的香菇多糖色素含量较高,实验采用活性炭对香菇多糖进行脱色,探讨了活性炭用量、吸附时间、pH值、脱色温度对脱色的影响,确定了脱色的最佳工艺。     

桃胶的水解及脱色条件研究

本研究主要是在原粗桃胶的基础上,开展不同因素的水解条件并通过对活性炭的温度、水解液值、活性炭的使用量、脱色时间等单因素条件的试验,优化最佳工艺。确定的最佳水解条件为:水解温度80℃~85℃,水解时间2 h,水解液pH值10.5,固液比6%。活性炭脱色应将温度控制在40℃~50℃,酸性条件下,活性炭用量为1.5%~3%,脱色时间为越长越好。     

蔗渣木糖提取液活性炭脱色工艺的研究

为了优化蔗渣木糖提取液脱色工艺条件,研究了4种活性炭对蔗渣木糖提取液吸附脱色效果的影响.结果表明,活性炭C1具有优良的吸附脱色效果.在以活性炭用量6%、起始pH值为4.5、脱色温度为40℃、脱色时间为60min条件下,蔗渣木糖提取液色素吸附率为96.34%,蔗渣木糖的回收率达88.24%,脱色效果良好.     

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