基于Design-Expert 软件设计优化大蒜多糖提取工艺

主要研究大蒜多糖提取的4种影响因素及其交互作用对大蒜多糖提取率的影响,借助于Design-Expert软件设计,优化大蒜多糖提取工艺条件,以期为开发利用大蒜多糖提供参考。采用水煮醇沉法提取大蒜多糖,以苯酚-硫酸法检测其含量,分别考察浸提时间、料液比、浸提温度及浸提次数对大蒜多糖得率的影响。在单因素试验的基础上,利用Design-Expert软件进行四因素三水平Box-Behnken试验设计,建立了大蒜多糖提取率和各因素之间的数学模型。结果表明,提取温度、液料比、提取时间和提取次数的一次项,个别交互项及其二次项对大蒜多糖得率的影响显著,而液料比与提取时间,液料比与提取次数的交互项作用不明显。大蒜多糖提取最优条件最终确定为:提取温度81℃,液料比14∶1(m L/g),提取时间84 min,提取次数2次。     

黄鸡枞子实体多糖提取工艺优化研究

以多糖得率为评价指标,采用水提醇沉法对黄鸡枞多糖的提取工艺条件进行优化,选用单因素试验和正交试验法,考察料液比、提取温度、浸提时间3个因素对该菌多糖得率的影响。结果表明,影响黄鸡枞水溶性多糖提取率的主要因素依次为料液比提取温度浸提时间,通过正交试验确定该菌多糖的最佳提取条件为料液比1∶30,浸提温度60℃,浸提时间2 h,在此条件下,其多糖得率可达4.7%,为改善黄鸡枞多糖的提取方法提供了试验基础。     

响应面法优化核桃分心木多糖的提取工艺

通过单因素试验研究了浸提温度、浸提时间、料液比和乙醇体积分数4个因素对核桃分心木多糖得率的影响。在此基础上,以多糖得率为响应值,采用响应面法对分心木多糖提取工艺进行优化。结果表明,影响分心木多糖得率的顺序为:浸提时间>乙醇体积分数>浸提温度>料液比;提取核桃分心木多糖的最佳条件为:乙醇体积分数90%,料液比1 g:50 mL,浸提温度95℃,浸提时间156 min。在最佳提取条件下,多糖得率为3.53%,与响应面预测值相差不大。     

响应面分析法优化莲花蜂花粉多糖提取工艺研究

为研究水提法提取莲花蜂花粉多糖的条件,在单因素试验的基础上,根据Box-Behnken 试验设计原理,选取料液比、浸提时间和浸提温度三因素三水平进行响应面分析,建立多糖提取率的二次回归方程,得到提取工艺的优化组合条件。结果表明：料液比、浸提时间和浸提温度对莲花蜂花粉多糖提取率都有显著影响,当提取工艺条件为料液比1:9.4(g/mL)、浸提时间2.4h、浸提温度81.6℃、浸提2 次时,莲花蜂花粉多糖提取率预测值为1.2201%、验证值为1.2317%。     

复合酶法提取石榴皮多糖的工艺研究

对复合酶(纤维素酶、果胶酶和木瓜蛋白酶)提取石榴皮多糖的工艺条件进行研究。以陕西临潼石榴皮为材料,运用正交试验法确定了复合酶的最佳加入量配比。比较了酶解时间、温度、pH以及液料比对多糖得率的影响,通过正交试验确定了最佳酶法提取条件。结果表明复合酶的最佳加入量配比为:纤维素酶120 U/g,果胶酶150 U/g,木瓜蛋白酶90 U/g;提取因素对多糖得率的影响大小为:pH温度时间料液比;最佳酶解提取条件为:浸提时间为120 min、温度为53℃、浸提液pH为4.6、料液比为1:55 g/m L。此条件下石榴皮多糖得率为6.01%。此法可使石榴皮多糖得率比传统水提法提高2倍,是一种提取效率高、温和的多糖提取方法。     

响应面分析法优化油菜花粉多糖提取工艺的研究

研究油菜花粉中水溶性多糖的提取工艺。在单因素试验的基础上,根据Box-Behnken中心组合试验设计原理,选取水料比、提取时间和提取温度3个因素的3个水平进行响应面分析,建立多糖得率的二次回归方程,得到提取工艺的优化组合条件。试验结果表明:水料比、提取时间和提取温度对水溶性多糖得率都有较显著影响,当提取工艺条件为水料比17.4∶1,时间3.4h,温度83.3℃时,多糖得率达到极大值。此条件下水溶性多糖得率预测值为1.4427%,验证值为1.4823%。     

藜麦多糖提取工艺的响应面法优化及其品种差异

研究藜麦种子多糖的最佳提取工艺条件及其品种间的多糖得率差异。采用水浴加热回流法,在单因素试验的基础上,选取提取温度、料液比、浸提时间进行3因素3水平的Box-Behnken中心组合研究,并运用Design Expect 8.0软件对试验数据进行分析,通过响应面分析法对提取条件进行了优化。结果表明,藜麦种子多糖的最佳提取工艺为:提取温度91℃,浸提时间1.5 h,料液比1:34,在此条件下,多糖得率在理论上可达15.81 g/100 g。各因素对多糖提取率的影响程度依次为:料液比提取温度浸提时间;同时发现藜麦种子多糖得率存在明显的品种间差异,其中品种"Quinoa B.Rain Sow"的多糖得率最高,达到15.889 g/100 g。     

油橄榄果渣中多酚提取工艺的优化

采用加热回流提取法,研究了浸提温度、乙醇浓度、料液比和浸提时间对油橄榄果渣多酚提取得率的影响。在单因素试验的基础上,通过正交试验对提取条件进行了优化,得到了油橄榄果渣中多酚的最优提取工艺:浸提温度为60℃、乙醇浓度为75%、料液比为1:13、浸提时间为4 h,油橄榄果渣多酚提取得率为0.2469%。     

茶树花多酚提取工艺的研究

用常规水浴浸提法和超声波辅助浸提法来提取茶树花中的多酚，研究了浸提温度、时间、料液比等因素对多酚得率的影响，比较得出超声波辅助浸提用时短，温度低的优点；通过正交试验设计，研究了各因素对多酚浸提影响的主次顺序，确定了最佳提取参数。实验结果采用统计软件（SPSS）进行分析，影响超声波辅助浸提各因素的主次顺序为料液比、温度、浸提时间,超声波辅助浸提最佳工艺为：温度50℃、提取时间10min、料液比1：30，在此工艺条件下多酚浸提得率75．13ms／g干花。为茶树花资源深度研究开发提供依据。     

油菜花粉多糖提取工艺条件研究

对油菜花粉多糖的提取工艺进行研究。探讨浸提次数、时间、料液比和温度对多糖得率的影响,在单因素试验的基础上,通过正交试验确定最佳提取工艺条件。结果表明:温度对多糖得率的影响最大,其次为提取时间、次数,料液比的影响最小。油菜花粉多糖提取的最优条件为1:4的料液比,90℃水浴条件下,浸提4次,每次浸提4h,其水溶性多糖提取率达1.450%。     

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