乙醇浸提法制备亚麻籽浓缩蛋白工艺研究

以冷榨亚麻籽饼为原料,采用乙醇浸提法制备亚麻籽浓缩蛋白。采用单因素试验研究了浸提工艺参数(浸提温度、浸提时间、乙醇体积分数、液固比以及浸提次数)对产品蛋白质含量的影响。在单因素试验基础上,采用正交试验进行工艺参数优化。结果表明,在所考察的范围内,各因素影响的主次顺序为乙醇体积分数浸提时间浸提温度液固比;最优工艺条件为浸提温度50℃、浸提时间75 min、乙醇体积分数70%、液固比6∶1、浸提次数2次,在此条件下亚麻籽浓缩蛋白的回收率为63. 87%,蛋白质含量为65. 38%。     

乙醇浸提法制备菜籽浓缩蛋白的工艺研究

本实验采用乙醇浸提法制备菜籽浓缩蛋白,在单因素试验的基础上,采用L9(34)正交优化试验,探讨乙醇浓度、浸提温度、浸提次数和料液比对浓缩蛋白产品蛋白含量的影响。单因素试验结果表明,最佳浸提工艺参数分别为：乙醇浓度70%、浸提温度60℃、浸提次数5 次,料液比1:7、每次浸提25min。正交试验结果表明：影响蛋白含量的主要因素为乙醇浓度,其次为浸提温度、料液比、浸提次数。最佳浸提工艺条件为A3B2C2D2,即乙醇浓度70%、浸提温度55℃、料液比1:6,浸提次数5 次。在此条件下制备的浓缩蛋白产品蛋白含量为60.5%,浓缩蛋白得率为75.7%,浓缩蛋白产品中抗营养因子成分——单宁、植酸、硫甙分别被脱除90.5%、66.7%、99.3%。     

热榨芝麻饼生产浓缩蛋白工艺条件的研究

以热榨芝麻饼为原料,利用正己烷-50%乙醇混合溶剂浸提生产芝麻浓缩蛋白。以混合溶剂中乙醇体积分数、醇洗时间、固液比和浸提温度为考察因素,进行单因素实验和正交实验,研究热榨芝麻饼生产浓缩蛋白的最佳工艺。结果表明,芝麻浓缩蛋白最佳生产工艺条件为:混合溶剂中乙醇体积分数55%,浸提温度55℃,固液比1∶6,醇洗时间85 min。在最佳条件下所得芝麻浓缩蛋白的粗蛋白质含量为66.89%,粗脂肪含量为0.53%,氮溶解指数为2.56%。     

加工条件对醇法大豆浓缩蛋白溶解性及结构的影响

为探究工业化生产的醇法大豆浓缩蛋白溶解性较差的原因，研究了醇法加工条件(乙醇体积分数、浸提温度、干燥温度)对大豆浓缩蛋白溶解性及结构的影响。结果表明：大豆浓缩蛋白的溶解度随着乙醇体积分数的增大呈现先降低后升高的趋势，乙醇体积分数为65%时溶解度最低；浸提温度和干燥温度的升高会导致溶解度大幅降低；随着浸提液中乙醇体积分数的增大，大豆浓缩蛋白表面疏水性、分子间的疏水相互作用、二硫键含量及粒径均呈现先增加后降低的趋势，在乙醇体积分数为65%时最大，而α-螺旋含量增加，β-折叠含量整体先增加后降低，无规卷曲含量降低；随着浸提温度和干燥温度的升高，大豆浓缩蛋白分子间氢键作用力降低，而表面疏水性、分子间疏水相互作用、二硫键含量和粒径增大，α-螺旋向β-折叠及无规卷曲转变，蛋白质结构趋于无序。综上，工业化醇法加工工艺(60%～70%乙醇体积分数、50～60℃浸提温度、60～70℃干燥温度)所引发的大豆浓缩蛋白表面疏水性的增大、分子间聚集程度的增加等导致了其溶解度的降低，不利于后期应用。     

从小麦胚芽里提取天然维生素E的试验研究

对传统溶剂法浸提小麦胚芽中维生素E浸提条件进行了一系列的研究。通过试验确定浸提溶剂、最佳的颗粒度和水分含量,用料液比、浸提温度、浸提时间、乙醇体积分数进行单因素试验并通过实验计算得到最佳的控制条件。实验结果表明：乙醇体积分数为95%,浸提温度为70℃,料液比为1：3,浸提时间为120 min,此时的浸提效果最佳。     

豆粕蛋白浓缩工艺的研究

以市售豆粕为原料优化蛋白浓缩工艺,考察浓缩过程中洗脱时间、洗脱次数、豆粕目数、乙醇体积分数、液料比值和洗脱温度等因素对蛋白浓缩效果的影响。在单因素的试验基础上,选择洗脱时间、乙醇体积分数和液料比值进行响应面分析试验,通过建立二次回归方程,对响应面分析可得到浓缩豆粕蛋白的优化组合条件。结果表明,洗脱时间1.5 h,乙醇体积分数65%,液料比值6(mL/g),豆粕目数50目,洗脱次数2次,洗脱温度30℃时,豆粕中蛋白百分含量为62.90%,比浓缩前提高了30.20%,得率为98.15%。     

醇法大豆浓缩蛋白浸提工艺研究

主要介绍了乙醇浸提法生产大豆浓缩蛋白的浸提工艺。探讨了主要工艺参数:乙醇浓度、浸提时间、浸提温度对整个浸提工艺的影响。通过正交试验确定了醇法生产大豆浓缩蛋白的最佳浸提工艺条件为:乙醇浓度70%,浸提时间90 m in,浸提温度50℃,在此条件下生产的大豆浓缩蛋白其蛋白含量可达到75.48%。     

文冠果种仁冷榨饼制取醇洗浓缩蛋白的研究

以文冠果种仁冷榨饼为原料,利用醇洗工艺制取醇洗浓缩蛋白。通过单因素试验和正交试验得到的最佳工艺条件为:乙醇体积分数55%,醇洗时间60 min,醇洗温度50℃,液料比10∶1,醇洗次数2次。各因素对蛋白质含量的影响大小顺序依次是乙醇体积分数醇洗温度液料比醇洗时间。在最佳工艺条件下所得文冠果种仁醇洗浓缩蛋白的蛋白质含量为67.80%,氮溶解指数(NSI)为35.10%。文冠果种仁醇洗浓缩蛋白是一种优质的食用浓缩蛋白。     

大黄鱼鱼卵(籽)磷脂提取工艺及其脂肪酸组成分析

采用乙醇溶剂法提取大黄鱼鱼卵(籽)磷脂的工艺条件。通过单因素试验研究乙醇体积分数、浸提次数、料液比、浸提时间和浸提温度对磷脂提取率的影响。在此基础上,采用Box-Behnken设计方法进行响应曲面法试验设计,确定最佳工艺:乙醇体积分数95%,浸提3次,料液比1∶10 g/m L,浸提时间30 min,浸提温度40℃。在此条件下,鱼卵粉磷脂提取率的平均值为(62±0.38)%,接近模型预测值。采用气相色谱法分析大黄鱼鱼卵(籽)磷脂的脂肪酸组成,结果表明,磷脂中含有20种脂肪酸,多不饱和脂肪酸有9种,占总脂肪酸含量的17.35%,其中EPA和DHA占总脂肪酸含量的15.19%。     

高温花生饼粕生产醇洗浓缩蛋白工艺条件的研究

以高温花生饼粕为原料,采用醇洗工艺生产花生浓缩蛋白。通过单因素实验和正交实验得到高温花生粕醇洗的最佳工艺条件为:乙醇溶液体积分数55%,浸提温度70℃,料液比1∶8,浸提时间80 min,浸提次数2次。在此条件下所得花生粕醇洗浓缩蛋白的粗蛋白含量(干基)68.92%,残油率0.79%。利用同样条件所得高温花生饼醇洗浓缩蛋白的粗蛋白含量(干基)65.23%,残油率3.32%。高温花生粕乙醇浸提糖蜜组分:水分35.02%,粗蛋白10.73%,总脂肪4.36%,磷脂0.783%,总糖33.53%,灰分9.87%;高温花生饼乙醇浸提糖蜜组分:水分28.19%,粗蛋白11.59%,总脂肪10.02%,磷脂0.806%,总糖38.76%,灰分7.14%。     

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