酶解-球磨法制备微细化淀粉的性质研究

传统微细化小颗粒淀粉的制备采用原淀粉直接球磨的方法,耗时长,能耗高,产物易糊化。采用先酶解再球磨的新工艺制备微细化小颗粒淀粉,并与玉米原淀粉、原淀粉球磨淀粉的性质进行比较。结果表明:玉米原淀粉的表面积平均粒径为12.90μm,原淀粉球磨淀粉的表面积平均粒径略有增大,而酶解-球磨淀粉的表面积平均粒径显著降低;酶解-球磨淀粉的结晶结构受到一定程度的破坏,部分偏光十字消失,双折射强度减弱,结晶度显著降低。     

木薯淀粉微细化及颗粒形貌的研究

通过采用机械球磨方法对木薯淀粉颗粒进行粉磨,研究了球磨时间对淀粉颗粒粒度分布及经表面积的影响规律,并根据球磨前后的淀粉颗粒形貌分析了淀粉颗粒破碎的方式及过程,结果表明机械球磨方法能有效地使木薯淀粉颗粒微细化。     

微细化莲子淀粉理化性质研究

采用球磨的方式对莲子淀粉进行了微粉碎,采用winner3001粒度分析仪对微细化淀粉的粒度中位径进行测量分析,研究了粉碎前后淀粉颗粒的粒度分布及比表面积的变化,结果表明机械球磨方法能有效地使莲子淀粉微细化。微细化导致莲子淀粉与水的结合能力增强,溶解度、膨胀度、透光率和吸湿性增强。     

流化床气流超微粉碎不同操作参数对玉米淀粉粒度的影响

目的 研究流化床气流超微粉碎不同操作参数对玉米淀粉颗粒粒度的影响。方法 以玉米淀粉为原料,通过流化床气流粉碎处理,考察原料不同含水量、不同粉碎气体压力、分级轮转速、持料量等参数条件下气流粉碎处理对淀粉颗粒粒径、粒度分布、比表面积、粉体密度及流动性的影响。结果 不同操作参数对淀粉颗粒粒度影响显著,在原料含水量6.18%,气体压力0.8 MPa、持料量1.0 kg、分级转速3600 r/min操作参数条件下获得微细化玉米淀粉粒径最小,中粒径D50为5.22μm,淀粉粒径大小显著降低,微细化玉米淀粉的粒度分布较窄且均匀,颗粒比表面积较原淀粉增大1.8倍,为0.65m²/g,颗粒球形度较好;粉碎降低了淀粉粉体密度,最佳条件下淀粉松装密度和振实密度分别为0.48 g/cm³和0.70 g/cm³,粉体流动性变差。结论 该研究为玉米淀粉资源的加工与应用提供了理论依据与技术支持。     

微细化淀粉颗粒形貌及显微结构分析

采用真空球磨设备,以食用级马铃薯淀粉、木薯淀粉及玉米淀粉为原料,制备不同粒度的微细化淀粉,并对淀粉粒度变化、形貌及聚集态结构等进行表征。扫描电镜形貌分析表明,淀粉颗粒在球磨处理过程中,其形貌特征发生了明显的变化,淀粉颗粒破碎首先发生在颗粒的缺陷处、裂纹处、结晶区处等应力相对集中的区域,当球磨处理时间继续增加时,会呈现一种细化与团聚并存的动态平衡;研究中还发现,淀粉在微细化处理中,并不单是淀粉表面薄层逐渐剥落的过程,大多淀粉颗粒呈现出大块层破碎、淀粉核心崩解等现象。     

气流超微粉碎对玉米淀粉微观结构及老化特性影响

以蜡质玉米淀粉、普通玉米淀粉和高直链玉米淀粉为原料,利用流化床气流粉碎机制备超微粉,采用激光粒度分析仪、扫描电子显微镜、X射线衍射仪、傅里叶变换红外光谱仪、凝胶渗透色谱结合多角度激光光散射仪、差示扫描量热仪等研究气流超微粉碎处理对淀粉颗粒大小、微观结构以及老化特性的影响。结果表明,3种淀粉经微细化处理后,粒径分别减小至6.05、5.22μm和5.53μm,比表面积增大,形态变得无规则,颗粒表面粗糙且有裂纹;淀粉颗粒晶体结构受到破坏,微细化蜡质玉米淀粉相对结晶度降低13.97%,降低程度大于普通玉米淀粉(13.31%)和高直链玉米淀粉(9.44%),粉碎过程无新的基团产生,但使淀粉分子链发生断裂、分子质量减小及分布变宽;微细化处理降低了淀粉的糊化温度和热吸收焓,改变了淀粉重结晶成核方式,降低低温贮藏环境玉米淀粉老化速率,延缓淀粉回生,利于淀粉质食品贮存和性质稳定;微细化处理对不同直链与支链比例玉米淀粉的粉碎效果、微观结构及性质影响存在差异。     

微细化马铃薯淀粉的生物降解性能研究

用机械球磨方法制备不同粒度的微细化马铃薯淀粉,采用半生物体内模型系统研究它们的生物降解性能。结果表明,颗粒的微细化有利于淀粉的生物降解微细化程度越高,淀粉越易被降解。超细马铃薯淀粉颗粒具有良好的生物降解性能。通过控制粒度大小可调节淀粉的生物降解速度和降解程度。     

球磨微细化处理对硬质小麦淀粉理化特性影响研究

以郑麦366淀粉和美硬NS淀粉为原料,通过球磨微细化处理对淀粉的理化特性进行改性。结果表明:球磨时间对淀粉的颗粒特性和淀粉糊特性均有较大影响,随着球磨时间延长,淀粉中损伤淀粉含量增幅较大。球磨6 h处理后淀粉颗粒中偏光十字大部分消失;与原淀粉相比,淀粉糊透明度、沉降体积、冻融稳定性均降低,而热水溶解度却呈上升趋势。     

混合酸交联高温溶胀制备非晶颗粒态淀粉

采用已二酸和醋酸酯的混合酸交联处理玉米淀粉,然后对交联淀粉水浴加热至80℃制备非晶颗粒态淀粉.本文考察了不同的交联剂用量对玉米原淀粉非晶化的影响.用偏光显微镜观测处理后淀粉颗粒结构,结合X射线衍射曲线确认淀粉由多晶态向非晶态的变化.结果表明,当交联剂用量达到13%（淀粉干基）的时候,玉米淀粉可由多晶颗粒态的原淀粉制备出只含无定形结构的非晶颗粒态淀粉.     

球磨微细化处理在植物性原料微粉制备中的应用研究

球磨微细化处理在植物性原料微粉制备中的研究和应用日益广泛。介绍了球磨微细化处理对植物性原料微粉品质特性的影响,以及微粉制备过程中工艺参数的优化。研究颗粒形貌变化与粒径大小、粒度分布的关系以及形貌的变化,对能耗的影响具有重要意义;采用前期剪切粉碎后期球磨处理的组合方式,可缩短原料的球磨时间,降低能耗。     

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