硅橡胶复合膜用于白酒风味成分分离的实验研究

利用PDMS平板复合渗透汽化膜对基酒进行膜分离研究,并用气相色谱法对冷凝液、渗余液进行定性及定量分析.膜分离实验条件为反应罐温度30℃,采用一级冷凝,温度-30℃,真空度0.1 MPa,流量100 L/h.结果表明,渗透汽化膜有良好的分离性能,可得到高酒精度、香味物质富集的冷凝液;过膜速率:乙醇＞酯类(乳酸乙酯除外)＞醛类＞其他醇类＞水;膜对乙醇选择性好,己酸乙酯的过膜率及过膜速率高;乳酸乙酯、醛类及甲醇过膜率较小、损失量较大;渗透汽化膜用于白酒的香气成分分离有良好的工业应用前景.     

硅橡胶复合膜用于白酒风味成分渗透汽化分离的实验研究

利用自制PDMS平板复合膜 ,在 30℃、膜下侧压力为 - 0 0 95Mp(6 0mmHg真空度 )的条件下 ,分别对浓度为 5 2°的成品酒和 72°的基酒进行渗透蒸发分离其中的风味物质。实验结果表明新型PDMS复合膜对白酒风味物质具有良好的分离性能 ,原酒中 5种酯类 (乳酸乙酯除外 )和乙缩醛的分离脱除率在 88%以上 ,对高级醇也有良好的分离表现 ,乙醛的脱除率超过 70 % ,在高浓度的乙醇中能保持良好稳定性。在 5 2°成品酒实验中平均总渗透通量达到 2 0 70g/ (m2 ·h) ,平均分离因子 (按乙醇 -水计算 ,下同 )为 4 9;在 72°基酒实验中平均总渗通量为 2 330g/ (m2 ·h) ,平均分离因子为 3 1。     

硅橡胶复合膜用于改进新型白酒品质的研究

利用一种自行研制的新型的PDMS平板复合膜 ,在温度 4 0℃、膜下侧压力保持为 - 0 .0 95Mp(6 0mmHg真空度 )的条件下 ,对浓度为 5 0°的新型白酒进行渗透汽化分离实验。实验结果表明通过该膜的膜下部分的白酒品质得到很大提高。通过对膜分离前后白酒风味物质的分析 ,该有机膜对白酒风味物质具有良好的选择透过性能 :新型白酒中 5种酯类 (乳酸乙酯除外 )和乙缩醛的过膜率达 10 0 % ,对高级醇也有良好的选择透过性表现 ,乙醛的过膜率也超过 87%。另外 ,通过该膜后 ,白酒中的水和酒精的缔合明显增加 ,乙醛明显降低的同时乙缩醛反而比过膜前增加不少 ,证明通过膜分离白酒中的乙醛发生缩合反应。该膜在提高新型白酒的品质应用上具有很大的前景     

硅橡胶复合膜用于发酵-渗透汽化耦合生产苹果白兰地的研究

香味物质对苹果白兰地的品质起着至关重要的作用.传统蒸馏方法的高温处理会不可避免地造成香味物质的损失和热敏性物质的破坏,影响白兰地的品质.采用苹果原汁发酵与渗透汽化膜分离相耦合的模式.在较低的温度下进行发酵,用硅橡胶复合膜将发酵液中的乙醇及其他挥发性香味成分选择性地分离出来,缩短了发酵周期,有效地避免了热敏性香味物质的损失.硅橡胶膜对发酵液中的乙醇及各种香味物质发挥了优良的渗透汽化分离性能,25℃平均总渗透通量为575.0 g/(m2·h),平均分离因子为5.44,20℃平均总渗透通量为332.2g/(m2.h),平均分离因子为4.75.所得产品清澈透明,酒度适宜,有浓郁酒香和苹果香.气相色谱分析结果表明,产品成分与传统蒸馏法所得的白兰地类似,主要香味物质含量符合相关技术要求,是制造高品质苹果白兰地的优质原型酒液.     

基于乙醇协同作用的柠檬油提取废液中挥发性芳香物的渗透汽化膜分离性能研究

采用涂布法自制了聚二甲基硅氧烷/聚偏氟乙烯树脂（Polydimethylsiloxane/Polyvinylidene Fluoride,PDMS/PVDF）渗透汽化复合膜,用于柠檬精油加工废液中挥发性芳香物的渗透汽化分离。考察了复合膜对橙花醇、α-松油醇和芳樟醇等三种柠檬精油废液中特征性芳香物的渗透汽化分离性能,结果显示,复合膜对3种化合物具有很好的分离选择性,但渗透通量均较低。添加乙醇对芳香物的分离效果有显著影响,当乙醇添加量为5% V/V时,橙花醇和芳樟醇的渗透通量较未加乙醇时提高了82.93%和127.76%,而α-松油醇的渗透通量则随着乙醇浓度的升高先升高后缓慢下降。测试了PDMS/PVDF复合膜对实际柠檬油废液中挥发性芳香物的分离效果,经渗透汽化处理6 h后,柠檬油废液中挥发性芳香物的种类及含量均明显降低,橙花醇、α-松油醇和芳樟醇的回收率分别为92.5%、93.37%、60.36%,应用效果良好。     

来稿摘刊

渗透蒸发原理及在食品加工中的应用施正学等浙江农业大学食品系（杭州）310029渗透蒸发是膜分离技术中较新的一种技术，使用致密高分子膜对混合液体作组分分离。物质跨膜迁移经过三个步骤：①液体与膜接触，溶入膜表面。②液体选择性地分子扩散方式透过膜。③液体从膜的另一表面蒸发、气化。过程中的推动力是膜两表面的浓度差，渗透蒸发过程中料液无需加压。分离膜有亲水性与疏水性两大种。通常采用复合膜。此种技术可用于①酒类、含醇饮料脱乙醇。采用亲水性膜、葡萄酒中大多数芳香成分可得到保留。②芳香成分回收。用疏水性膜，回收效果颇…     

基于渗透汽化膜生产脱醇酒的香气成分及功能特性变化

为保证渗透汽化膜生产脱醇酒的品质,将新疆赤霞珠干红葡萄酒原酒经渗透汽化法制得脱醇酒,测定两种样品中香气成分、多酚物质含量、抗氧化指标并进行动物试验,探究脱醇酒香气及其功能特性的变化。结果表明：两种样品中共含有45种香气化合物,其中原酒香气含量为464.36 mg/L,脱醇酒香气含量为301.75 mg/L,脱醇酒总酚、总黄酮、总黄烷-3-醇、总花色苷含量较原酒分别上升21.59%、25.21%、20.00%、35.64%,DPPH、ABTS以及羟基自由基的清除力分别上升17.45%、9.19%、2.82%,动物试验中相较于对照组,原酒与脱醇酒组的大鼠血清中超氧化物歧化酶（Superoxide Dismutase,SOD）分别升高27.43%、74.97%;过氧化氢酶（Catalase,CAT）分别升高224.69%、566.14%;过谷胱甘肽过氧化物酶3（Glutathione Peroxidase-3,GPX3）分别升高21.45%、102.19%。综上,脱醇酒的香气成分保留度较高风味较好,抗氧化等能力都有一定程度提升,说明了脱醇酒具有的功效特性,为脱醇酒产业提升脱醇酒品质提供理论依据。     

膜法分离无水乙醇研究进展

论述了两种膜法分离技术--渗透汽化法和蒸汽渗透法从近似共沸物中分离无水乙醇的研究现状,列出了渗透汽化法中具有工业应用前景的复合膜材料及中空纤维膜组件的研究结果,并对两种膜法分离技术进行了较全面的比较.     

固定化酵母-膜生物反应器连续发酵生产乙醇的研究

对固定化酿酒活性干酵母-硅橡胶膜生物反应器连续发酵生产乙醇进行了实验研究。对固定化酵母和游离酵母的发酵能力进行了比较,实验研究了系统在长期运行过程中的发酵反应动力学参数和膜传质动力学参数等基本性能。结果表明,酵母细胞固定化后,其发酵速度有明显提高;膜渗透汽化分离产物乙醇使发酵反应能够长时间连续稳定地进行,葡萄糖消耗率和乙醇体积产率都较间歇发酵有明显的提高;在连续运行中,发酵液中葡萄糖浓度控制在20～50g/L的范围内,乙醇体积产率为4.0g/（L·h）,罐内乙醇浓度基本保持在45g/L左右,固定化酵母浓度维持在1.05×10^10～2.15×10^10个/克胶,发酵液中游离酵母浓度维持在0.02×10^10～0.098×10^10个/mL,膜的渗透通量和分离因子分别为300～500g/（m^2·h）和3.6～7.2;实验系统连续运行了294h,收得渗透冷凝液4841.7g,平均质量分数为21.3%。     

膜过滤技术在低醇葡萄酒生产过程中的应用

利用中空纤维膜截留酵母菌,中止酒精发酵,生产低醇葡萄酒。使用UEIS905膜进行超滤,通过循环超滤,整个过程为25℃、0.2MPa下循环60min～100min,超滤后葡萄酒的酒精度为5%vol,酒体澄清度较高,风味丰满圆润。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.