超声辅助提取佛手废渣果胶的工艺优化

目的：对佛手废渣果胶提取工艺进行优化。方法：分别通过响应面试验和正交试验对果胶的超声辅助酸提和乙醇沉析工艺进行优化。结果：响应面试验优化后的超声辅助酸提工艺条件为浸提时间37min、浸提温度63℃、超声功率395W、pH1.6。正交试验优化后的醇析条件为浓缩比1:4、醇析温度15℃、醇析时间1.5h、醇析液pH2.0、醇析液乙醇体积分数70%。结论：经验证在最佳工艺条件下,果胶提取得率22.1%,果胶醇析得率85.7%。     

砂糖桔皮中果胶提取工艺研究

以干砂糖桔皮为原料,通过对料液比、浸提温度、浸提时间进行单因素试验和L9(33)正交试验,对桔皮果胶提取工艺进行优化。结果表明:桔皮果胶提取的最佳工艺条件为:料液比1∶30(g∶mL)、温度90℃、时间1.5 h,在此条件下桔皮中果胶得率为26.74%。将得到的砂糖桔皮果胶通过活性炭脱色、干燥处理,得到质量较好的果胶产品。     

八角茴香中莽草酸提取工艺优化研究

对八角茴香中莽草酸的提取工艺进行优化研究.以正交试验设计手段探讨出八角茴香中莽草酸的最佳提取工艺条件是:以蒸馏水为提取溶剂、原料粒度20目、温度65℃、料液比1 ∶ 15、提取时间2.5h,最佳结晶条件是:活性炭用量15％、活性炭脱色时间30 min、乙醇与水的体积比为2.5,此条件下莽草酸得率最高为2.43％.     

辣椒粕果胶提取工艺的优化

目的:研究辣椒粕果胶提取、脱色最优工艺。方法:以辣椒粕为原料,采用酸水超声提取果胶,以果胶得率为考察指标,在单因素试验的基础上,采用响应面设计,研究超声功率、超声时间、料液比对辣椒粕果胶提取率的影响;采用单因素实验,对果胶脱色工艺进行了优化。结果:优化辣椒果胶的提取工艺,得到最优工艺为:超声功率为450W,超声时间为35min,料液比为1∶21,优化的脱色条件为:活性炭用量0.6g/100m L、双氧水用量4m L/100m L、脱色温度70℃、脱色时间70min。按该工艺进行试验所得辣椒果胶得率为16.85%,与预测值基本一致,且产品符合QB2484-2000中规定的质量标准,通过验证实验也证实了利用Box-Behnken响应面法优选的辣椒果胶提取工艺稳定可行。     

苹果果胶脱色工艺优化及对面条蒸煮品质的影响研究

以吸附率为指标,采用正交法优化活性炭对苹果果胶的脱色工艺,并就苹果果胶对面条蒸煮品质的影响进行了探索.结果 表明:活性炭对果胶脱色效果的影响因素大小顺序为温度＞脱色时间＞活性炭添加量.最佳因素水平组合为温度60℃、脱色时间30 min、活性炭添加量10 g/L,在此条件下,活性炭对果胶脱色吸附率达到80.50％.当果胶...     

冷榨花生蛋白酶解液活性炭脱色工艺的响应面优化研究

基于单因素试验结果,运用中心复合响应面优化技术对冷榨花生蛋白酶解液活性炭脱色工艺进行了优化分析,探讨了脱色pH、活性炭添加量、脱色时间和脱色温度对酶解液脱色率和多肽损失率的影响规律,并分别建立了酶解液脱色率和多肽损失率的二阶多项式非线性回归方程和数值模型。响应面优化分析发现,用2.0%(占酶解液质量)的活性炭在pH 2.5、40℃条件下脱色60 min,脱色率为(89.12±5.42)%,多肽损失率为(8.62±1.27)%。验证试验结果与模型预测结果基本一致。     

冬枣多糖水提醇沉工艺研究

以冬枣多糖得率为指标,以水为提取溶剂,采用单因素和正交试验对多糖水提工艺和醇沉工艺进行了优化。结果表明,冬枣多糖的最佳水提工艺条件为浸提温度100℃、料液比为1︰25(g/m L)、浸提时间4 h;最佳醇沉工艺为提取液浓缩4倍,加入2倍量95%乙醇,醇沉8 h,多糖得率为14.16%,其中影响冬枣多糖水提工艺的先后次序为浸提温度、浸提时间和料液比;影响醇沉工艺的先后次序为提取液浓缩倍数、乙醇加量、醇沉时间和乙醇体积分数。     

仙人掌果胶提取工艺的研究

对用酸水解法从仙人掌皮渣中提取果胶的工艺条件进行了研究。通过正交实验得到最佳提取工艺条件为料液比1：12,用硫酸调pH值至2.0,95℃提取2h。按提取液体积的1%加入颗粒活性炭,60℃下脱色40min,离心分离液进行真空浓缩后添加酒精至浓度80%进行沉淀,分离后可得纯度为70%的果胶,其果胶提取率为17.8%(干基)。     

乙醇沉淀法从沙田柚皮提取果胶的研究

本文研究了用乙醇沉淀法以柚皮为原料提取果胶时工艺条件,发现水解液经过一定的浓缩后,有利用提高果胶得率,当乙醇浓度达到50％以上时,果胶提取率较高,乙醇浓度高,果胶质量好,最佳条件为浓缩倍数6-7,乙醇浓度60-70％,这时,果胶得率大于26％。     

菊粉分离纯化工艺的研究

以菊糖的保留率为指标,考察了除杂实验中菊糖溶液pH、除杂时间、水浴温度的影响,及其脱色实验中活性炭用量、温度、脱色时间等因素对保留率的影响,并利用正交试验对菊糖的除杂脱色工艺进行了优化,最后对产品采取分离纯化试验.试验结果表明,菊芋中菊糖除杂的优化工艺条件为:除杂温度70℃、水浴时间20 min、溶液最适pH=9;脱色的优化工艺条件为:脱色温度90℃、水浴时间20 min、活性炭用量4％(按体积百分含量加活性炭),然后抽滤除去活性炭,对滤液进行真空浓缩后在50℃条件下干燥,在以上综合条件下得到的菊糖纯度可达92％.     

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