化学法结合酶法提取牛蒡中的可溶性膳食纤维

本文以牛蒡为原料,先用化学方法处理得到牛蒡可溶性膳食纤维(SDF)和牛蒡渣,然后再用酶法处理前一步得到的牛蒡渣,进一步提取牛蒡可溶性膳食纤维。通过单因素试验及正交试验对化学法和酶法条件进行了优化。结果表明,化学法制备可溶性膳食纤维的较佳工艺条件是:温度100℃,反应时间20 min,pH10.0,物料比1∶15,在此条件下,牛蒡提取SDF得率为11.2%。使用复合多糖酶处理前一步得到的牛蒡渣,酶法提取可溶性膳食纤维的较佳条件为:复合多糖酶的用量8%、酶解温度40℃、酶解时间1h、pH 3.9、料液比为1∶18,在此条件下,SDF得率为4.82%。     

酶解法制备高活性水溶性膳食纤维的研究

采用木聚糖酶酶解的方法水解水不溶性膳食纤维(IDF),提取高活性水溶性膳食纤维(SDF),以水溶性膳食纤维(SDF)的得率为指标,通过单因素试验及正交试验得到酶解的最佳条件为p H5.0,温度50℃,木聚糖酶的加酶量为7.0%,反应时间2.5h,物料比1∶20(m∶v),在此条件下,高活性水溶性膳食纤维(SDF)的得率为12.10%,持水性为5.40%,膨胀力为10.13m L·g-1。本研究为水溶性膳食纤维这种新型功能性食品添加剂的提取及应用提供了参考。     

响应面法优化黑灵芝膳食纤维提取工艺

以黑灵芝为原料,采用酶法和化学法联用,从黑灵芝中提取出可溶性膳食纤维和不可溶性膳食纤维,借助响应面设计分析,考察酶解温度、酶解时间、料液比和碱提pH、碱提温度、碱提时间分别对黑灵芝可溶性膳食纤维(SDF)、不可溶性膳食纤维(IDF)得率的影响.结果表明,最佳提取工艺条件分别为:酶解温度98℃、酶解时间103min、料液比1∶32和碱提pH10、碱提温度48℃、碱提时间41min,在此条件下黑灵芝SDF得率为1.08％,IDF得率为88.68％.     

豆渣膳食纤维提取工艺预处理条件的研究

本文介绍的是以一种新的预处理手段一挤压技术,处理豆渣原料,从而提高可溶性膳食纤维(SDF)得率的制备工艺。通过单因素及L9(34)正交试验得出用豆渣提取膳食纤维(DF)最佳工艺条件为:氢氧化钠用量5%、胰蛋白酶用量0.13%、碱浸泡时间60min、碱浸泡温度80℃,产品中小可溶性膳食纤维(IDF)纯度为81.07%,可溶性膳食纤维(SDF)得率6.94%。由于近年来人们对可溶性膳食纤维(SDF)的生理功能越来越认可并关注,且相关报道层出不尽,并已知挤压技术的应用可提高膳食纤维中的可溶性膳食纤维(SDF)含量,其主要依据是纤维素在高温、高压、高剪切力和摩擦力的作用下大部分半纤维素和少数纤维素降解成可溶性膳食纤维(SDF)。因此,在豆渣制取膳食纤维(DF)的预处理过程中加入挤压工艺可显著提高其可溶性膳食纤维(SDF)的得率。通过L9(33)正交试验得出单螺杆挤压最佳工艺条件为:物料水分25%、挤压温度180℃、螺杆转速175r/min。在此工艺条件下,可溶性膳食纤维(SDF)的得率由6.94%提高到19.45%。     

联合酶法提取豆渣蛋白肽和可溶性膳食纤维

豆渣是大豆加工的主要副产物之一,含有丰富的蛋白质和膳食纤维。为促进豆渣高值化利用,采用联合酶法从豆渣中提取蛋白肽和可溶性膳食纤维（SDF）。首先用碱性蛋白酶酶解豆渣蛋白,以蛋白肽得率为指标,通过单因素试验优化了提取豆渣蛋白肽的工艺条件,再将脱蛋白豆渣用纤维素酶酶解制备SDF,以SDF提取率为指标,通过单因素试验优化提取SDF的工艺条件。结果表明：碱性蛋白酶酶解提取蛋白肽最佳工艺条件为料液比1∶ 35、酶与底物比2%、酶解时间5 h、酶解温度50 ℃、pH 95,在此条件下豆渣蛋白肽得率为66.81%;纤维素酶酶解提取SDF最佳工艺条件为料液比1∶ 30、酶与底物比3%、酶解温度50 ℃、酶解时间2 h、pH 4.0,在此条件下SDF提取率为1554%。利用碱性蛋白酶和纤维素酶依次酶解后,豆渣总利用率达到了89.81%,这为豆渣综合开发利用提供了一种新途径。     

蒜皮膳食纤维的促溶改性及抗氧化性研究

目的:提高蒜皮膳食纤维的可溶性、评价其抗氧化活性。方法:以蒜皮为原料,采用酶-重量法进行蒜皮膳食纤维(TDF)提取,以及不溶性膳食纤维(IDF)和可溶性膳食纤维(SDF)的分离,对于分离得到的IDF,通过单因素和正交实验,探索纤维素酶酶法改性的最佳工艺条件;对于蒜皮不溶性膳食纤维,通过纤维素酶法改性提高其可溶性。结果:蒜皮中TDF含量为69.18%,其中SDF含量为7.28%、IDF为61.9%;酶法改性的最优条件为:料液比1∶15g/mL、纤维素酶加酶量5%、酶解温度45℃、酶解时间4h、酶解pH6.5,此条件下蒜皮IDF的33.20%转化成为SDF;酶解后溶出的SDF溶液对羟自由基和DPPH自由基清除效果较好。结论:纤维素酶酶解可以显著改善蒜皮膳食纤维的溶解特性,改性后的蒜皮SDF具有较好抗氧化活性。     

响应面与酶法优化拐枣膳食纤维的提取工艺

以拐枣为试验材料,采用酶法对可溶性膳食纤维进行提取。在酶解温度、酶解时间、p H值、酶用量4个单因素试验基础上,利用Box-Behnken的中心组合设计原理进行响应面设计优化提取工艺参数。结果表明:拐枣中可溶性膳食纤维(soluble dietary fiber,SDF)得率最佳提取工艺条件为酶解温度60℃,酶解时间70 min,p H值为5.0,酶用量0.6%。拐枣中SDF得率可达14.22%,与SDF的提取理论值比较,其相对误差约为0.42%,且重复性好,说明响应面法建立的数学模型对拐枣中SDF提取具有稳定可靠性。     

豆渣膳食纤维生物改性和高效提取技术研究

针对豆渣的可溶性膳食纤维含量较少,通过采用生物发酵和纤维素酶处理技术对大豆膳食纤维进行改性,提高豆渣中可溶性膳食纤维(SDF)含量。在对改性豆渣提取SDF后,采用复合酶辅以超声波提取IDF工艺技术,在复合酶添加量0.6%,超声波功,400w,作用温度50oC,作用时间30min条件时,膳食纤维提取率87.21%,产品持水率、膨胀率得到提高。     

豆渣膳食纤维的制备工艺研究

本文对豆渣膳食纤维的制备工艺进行了研究。利用生物酶法改性提高豆渣中可溶性膳食纤维(SDF)含量,通过单因素实验和正交实验确定了纤维素酶酶解的最佳工艺。最佳工艺条件为:纤维素酶添加量0.5%,料液比1∶12,温度45℃,pH值4.5,酶解时间1.5h,乙醇沉淀时间1h,在此条件下,豆渣SDF得率可达到8.53%。在此基础上,制得了豆渣膳食纤维粉,其持水力和膨胀性分别为5.0783g/g和8.4675mL/g,色泽呈乳白色,具有豆渣膳食纤维固有的气味和滋味,质量指标达到国家二级标准。     

碱法与酶法提取大麦糟膳食纤维的比较

本研究以大麦糟为原料,分别用碱法与酶法提取大麦糟SDF(可溶性膳食纤维)与大麦糟IDF(不可溶性膳食纤维),并对两种方法提取的膳食纤维的得率、纯度、部分理化性质及感官品质进行了研究,经比较分析得出:碱法提取大麦糟膳食纤维与酶法相比有着成本低,得率高的优点.     

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