响应面优化复合酶法提取竹笋膳食纤维工艺

以竹笋为原料,在酶解时间、酶解温度、复合酶质量分数、复合酶质量比值4个单因素实验的基础上,通过响应面法对竹笋膳食纤维提取工艺条件进行优化。结果表明:最佳提取工艺条件为酶解时间95 min、酶解温度56℃、复合酶质量分数0.52%、复合酶质量比值为蛋白酶∶纤维素酶=3∶1,在此条件下竹笋膳食纤维提取率最大,为53.21%。     

响应面法优化花椒籽不可溶性膳食纤维提取工艺研究

以花椒籽为原料,采用酶-化学法从花椒籽中提取不可溶性膳食纤维.在单因素试验基础上,采用Box-Behnken中心组合试验设计,考察碱液质量分数、碱浸温度、碱浸时间、胰蛋白酶用量对不可溶性膳食纤维得率的影响.结果表明,回归模型能较好地反映各因素水平与响应值之间的关系;同时得出最佳提取条件为:碱液质量分数3.17%,碱浸温度49.93℃,碱浸时间40.86 min,胰蛋白酶用量0.4%;在最佳条件下,不可溶性膳食纤维得率为80.58%.     

麦糟不溶性膳食纤维的蛋白质降解工艺研究

优化酶碱法制备麦糟不溶性膳食纤维的过程中,蛋白质酶解和碱溶的工艺条件。通过单因子和正交试验,考察加酶量、酶解温度、酶解时间、NaOH浓度、碱溶温度和碱溶时间对不溶性膳食纤维的得率和蛋白质质量分数的影响,分析因素的主次顺序,优化工艺条件并验证。结果表明在酶解温度45℃,酶解时间3.5 h,加酶量为0.09 g,碱溶温度50℃,碱溶时间45 min,NaOH浓度1 mol/L的条件下,制备得到麦糟不溶性膳食纤维的得率为29.2%,蛋白质质量分数3.1%。结果为制备优质不溶性膳食纤维提供一定参考。     

RSM法研究麦糟不溶性膳食纤维的淀粉酶水解工艺

试验优化麦糟不溶性膳食纤维的淀粉酶水解工艺条件,考察因素对不溶性膳食纤维得率和不溶性膳食纤维中淀粉质量分数的影响。采用响应曲面(RSM)法分析因素的显著性,建立数学模型,优化工艺条件。建立了淀粉酶水解模型,模型高度显著且有效,可用于分析和预测淀粉酶水解过程。优化得到的最佳工艺条件为加酶量0.06 g,水解温度65℃,时间60 min,在该条件下,制备得到不溶性膳食纤维得率为28.8%,不溶性膳食纤维中淀粉质量分数为0.41%。     

山楂中水不溶性膳食纤维提取工艺的优化

以新鲜山楂果实为原料,采用酶化学法提取山楂果实中的水不溶性膳食纤维,通过单因素试验和正交试验优化工艺条件。结果表明,当碱加入量0.50%(样品质量分数),碱解温度45℃,液化淀粉酶用量为0.10%(样品质量分数),酶解时间35 min时,得到的水不溶性膳食纤维纯度高,总杂质去除率为97.8%,水不溶性膳食纤维的提取率为3.52%。所提取的水不溶性膳食纤维持水力为5.27 g/g、膨胀力为5.10 mL/g。     

麦麸膳食纤维提取条件的优化

本实验以麦麸为原料,采用酶-化学结合法制备膳食纤维,通过正交实验得出其最佳提取条件：α-淀粉酶用量为2.33%,酶解时间20min,碱浓度1mol/L,处理时间45min, 此条件下制备的膳食纤维得率为30.42%,纯度可达86%以上,其中可溶性膳食纤维含量为23.28%。     

酶法提取小麦麸皮膳食纤维工艺研究

以小麦麸皮为原料,采用酶法制备膳食纤维,通过正交实验得出最佳提取条件:α-淀粉酶用量0.4%,α-淀粉酶酶解时间50min,蛋白酶用量0.2%,蛋白酶酶解时间50min,此时小麦麸皮膳食纤维得率为81.3%。     

乙醇-过氧化氢纤维素酶提取甜菜膳食纤维工艺的研究

以甜菜干粕为原料,用乙醇和过氧化氢提取膳食纤维.分别以甜菜膳食纤维的膨胀力和持水力为评价指标,最佳提取工艺条件:乙醇体积分数65%,过氧化氢体积分数7%,水浴温度35℃,水浴时间75 min.在此条件下可以提高甜菜膳食纤维的膨胀力2.52%,提高持水力3.14%.用纤维素酶改性甜菜膳食纤维,分别以甜菜膳食纤维的膨胀力和持水力为评价指标,得到两种最佳改性条件:一是在酶用量600μL,反应温度60℃,pH 5.5,反应55min条件下处理,可以提高甜菜膳食纤维的膨胀力13.8%;二是在酶用量600μL,反应温度55℃,pH 5.5,反应65min条件下处理,可以提高甜菜膳食纤维的持水力19.7%.     

响应面法优化脐橙渣中水溶性膳食纤维提取工艺

以赣南脐橙渣为原料,采用纤维素酶制备水溶性膳食纤维。在单因素试验基础上,选取酶解温度、加酶量(质量分数)和酶解时间为响应变量,以水溶性膳食纤维得率为响应值,利用Box-Behnken试验设计方案和响应面分析法,建立水溶性膳食纤维得率与响应变量的回归方程,并确定最佳提取条件为酶解温度48℃、加酶量1.25%、酶解时间5h,此条件下水溶性膳食纤维得率为13.11%,与预测值13.14%较为一致。     

红薯膳食纤维物理-酶法的提取工艺研究

以红薯为原料,对物理-酶法提取膳食纤维的工艺进行研究。结果表明,物理筛分的前处理最佳工艺为浸泡料液比1∶4,浸泡时间8h,浸泡温度50℃;酶解工艺的最佳条件为酶解料液比1∶6,酶解时间1.5h,酶解温度50℃,酶解pH4.0,添加α-淀粉酶质量分数0.03%。在此条件下,原料淀粉去除率达到84.93%,得到的红薯膳食纤维中粗纤维含量达到82.33%。     

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