微乳的稳定性研究

本实验以单辛酸甘油酯,丙二醇质量比2∶1为油相;吐温80,乙醇质量比2∶1为表面活性剂相,双蒸水为水相制备出具有3条无限稀释通道的食品级微乳,通过粒径分析,浑浊度测定,Zeta电位比较,离心及稳定性实验,研究稀释,盐离子浓度,酸碱性,温度对单辛酸甘油酯微乳稳定性的影响。实验制备的T82-100微乳,在NaCl浓度0.1~0.6mol/L,pH3~8,温度0~40℃之间,吸光值0.015,采用食品级原料制备的单辛酸甘油酯抑菌性T82微乳不仅稀释稳定性强,且具有较好的耐盐离子、pH及温度特性,整个实验中均保持均一透明的稳定状态。结果表明示选择合适的表面活性剂、助表面活性剂及恰当的比例,能制备出全稀释的稳定微乳,这对扩大微乳在食品中的应用提供可能。     

玫瑰精油微乳制备及性质研究

为改善玫瑰精油的水溶性和稳定性,采用转相乳化法制备玫瑰精油微乳,优化微乳制备工艺,优化静态顶空法测定微乳包封率,并对储藏稳定性进行研究。结果表明:玫瑰精油HLB值≥15.5,微乳的最佳制备工艺为:吐温80为表面活性剂,乙醇为助表面活性剂,最佳Km值为2,S/O值为9,选用磁力搅拌法,最佳制备温度为40℃,当水分质量分数为90%时,平均粒径为10.43 nm,PDI为0.07,包封率达89%。制备的可稀释微乳粒径稳定,溶液澄清透亮,储存稳定性好。     

山茶油微乳液的制备及稳定性分析

以山茶油为原料,采用拟三元相图法优化微乳液配方并研究其稳定性。探讨助表面活性剂种类、表面活性剂与助表面活性剂质量比(Km值)和制备温度对形成微乳液的影响,通过计算并比较拟三元相图微乳区面积确定各因素的最佳值,然后采用电导率法区分山茶油微乳液类型,最后对其稳定性进行分析。结果表明,制备具有最大加水量的山茶油微乳液的最佳条件为:固定山茶油与肉豆蔻酸异丙酯(IPM)(质量比1∶2)作油相占比34%,加水量15%,Tween80与Span80质量比4∶1作表面活性剂,正丁醇为助表面活性剂,Km值4∶1,混合表面活性剂与油相质量比6∶4,制备温度25℃。在最佳条件下,微乳液的类型为W/O型,并具有良好的热稳定性、离心稳定性、储藏稳定性、耐盐性和耐碱性。     

全稀释食品级单辛酸甘油酯微乳体系的构建

以单辛酸甘油酯为油相,通过拟三元相图方法,研究了吐温20、60、80以及单硬脂酸甘油酯、尼泊金乙酯等表面活性剂,乙醇、丙二醇、正丁醇等助表面活性剂对于微乳体系增溶能力的影响.结果表明,添加醇有助于形成微乳体系,油相中醇的比例越高,微乳相越大,但表面活性剂相中醇的含量不易过多;微乳体系的水相全稀释性主要取决于油与表面活性剂的质量比Wo/Ws,在单辛酸甘油酯/吐温80/乙醇/水和单辛酸甘油酯/吐温80/丙二醇/水体系中,当Wo/Ws＞1时,即使添加足量的醇也无法形成全稀释微乳.而且,表面活性剂的复配不一定具有增效作用.最后,确定微乳配方为油相:单辛酸甘油酯与丙二醇质量比2∶1;表面活性剂相:吐温80与乙醇质量比为2∶1;水相:双蒸水.该食品级单辛酸甘油酯微乳单相区面积为73.81％,具有3条可无限稀释通道.盐离子浓度和pH的稳定性研究表明,该微乳体系在NaCl浓度0.1～0.6mol/L范围内稳定性较好,且受pH影响较小.     

全稀释食品级单辛酸甘油酯微乳的稳定性研究

以单辛酸甘油酯(GMC)为油相,吐温80为表面活性剂,丙二醇和乙醇为助剂,与水制备出具有高稀释性的食品级微乳.通过粒径分析,浑浊度对比,离心及贮藏试验,考察盐离子浓度、pH、温度、稀释对表面活性剂相与油相质量比分别为7∶3、8∶2的T73、T82稀释线上微乳贮藏稳定性的影响.结果表明,稀释会导致T73上微乳粒径增大,pH、盐离子、温度对水分含量高达99％的T73-100(用100倍表面活性剂相与油相质量比为7∶3的混合物质量的水相稀释)微乳稳定性影响较大;T82具有较好的稀释稳定性,且T82-100微乳分别在NaCl浓度0.1～0.6 mol/L,pH 3～8,温度0～40℃之间贮藏30 d后,平均粒径均小于35 nm.     

聚甘油单月桂酸酯-油酸微乳体系的构建及其性能

为构建安全高效的微乳体系,提高姜黄素的溶解度,拓展微乳液及姜黄素在食品中的应用,制备具有较高姜黄素溶解度、可无限稀释的食品级微乳液。以油酸和不同聚合度的聚甘油单月桂酸酯、不同碳链长的醇为原料,通过对拟三元相图的分析,筛选表面活性剂和助表面活性剂,研究表面活性剂与助表面活性剂质量比（Km）、水相pH值和NaCl浓度对微乳体系相行为的影响,用电导率法分析微乳液的结构,用激光粒度仪和透射电镜测定观察微乳液滴的粒径、微观形貌。结果表明,以质量比为2∶1的六聚和十聚甘油单月桂酸酯复配为表面活性剂,以乙醇为助表面活性剂,Km=1/2,制备的微乳液效果最好,微乳区域面积占比最大,微乳液滴呈均一球形,粒径在10～100?nm之间。非中性的水相、NaCl的加入均会导致微乳区域面积占比的减小和最小可稀释比的增大。当表面活性剂与油相质量比为9∶1时,能够形成可无限稀释微乳体系,该体系结构在含水量小于45%时为W/O型,继续增加含水量,体系结构逐渐转变为双连续型,含水量超过60%时为O/W型。姜黄素微乳化不影响姜黄素生物活性,且姜黄素的溶解度可达4.87?mg/mL,可有效地解决姜黄素溶解性差、稀释性差的问题,说明微乳液是姜黄素的优良载体。     

吐温/短链醇/丁酸乙酯/水微乳体系相行为及微观结构

通过绘制拟三元相图研究吐温/短链醇/丁酸乙酯/水微乳体系(MEs)的相行为，比较不同吐温表面活性剂、助表面活性剂短链醇及表面活性剂与短链醇的质量比(Km)对单相微乳区面积及全稀释通道数的影响，并基于NMR方法对吐温80/乙醇/丁酸乙酯/水单相微乳区全稀释线上(混合表面活性剂和油相的质量比9∶1，逐渐增大水相分数)的微观结构变化、分子运动性及分子间相互作用进行表征。揭示单相微乳区稀释线上可能存在油包水→有序双连续结构→水包油→肿胀胶束的微观结构变化；根据NMR-1D NOESY选择性激发试验结果推测双连续结构中各组分间的相互作用为:丁酸乙酯分子包裹在双层结构内部，与水分子较少接触；乙醇分子同时存在于液滴界面及水相中，与水相有直接作用；吐温80的亲水基团在界面外层与水相接触，疏水基团在界面内层伸向油滴内部，与水相无相互作用。     

番茄籽油微乳制备工艺的优化及稳定性研究

以番茄籽油为原料,通过对表面活性剂、助表面活性剂及油相等因素的选择优化,确定了番茄籽油微乳的基本制备工艺及其参数。结果表明:以Tween-80为表面活性剂、丙三醇为助表面活性剂,K_m(表面活性剂与助表面活性剂比值)值为2.68、混合表面活性剂与番茄籽油的比值为7.05时,乳化率为65.72%,乳化效果良好;同时考察了不同因素(高温、低温、光照、盐离子浓度和种类)对微乳稳定性的影响,研究表明微乳的低温、盐离子浓度稳定性较好,而高温、光照和盐离子种类稳定性较差。     

板栗花精油微乳的制备工艺

本文采用转相乳化法制备板栗花精油微乳,并通过伪三元相图考察表面活性剂、助表面活性剂、表面活性剂与助表面活性剂的比值(Km值)和油相对微乳形成的影响,以确定板栗花精油微乳的最优制备工艺参数。结果表明:板栗花精油微乳的最佳工艺为:聚乙二醇硬脂酸酯-15(HS-15)为表面活性剂,甘油为助表面活性剂,Km为2,油酸乙酯(EO)与精油等比例混合为油相,所制备的板栗花精油微乳为O/W型。以最佳微乳配方中混合表面活性剂与油相比例7∶3为试样,微乳的特性参数电导率、黏度和p H分别为180.2μs/cm,44.7 m Pa·s和6.66。此研究为板栗花精油微乳的制备及应用提供技术支持。     

食品级刺五加叶黄酮微乳的制备及功能特性

黄酮类物质的溶解度低,耐碱性和抗光解能力差,化学性质很不稳定,限制了其在食品中的应用,而微乳是一种良好的载体,可解决黄酮难以利用的问题。本研究应用滴定法绘制伪三元相图来考察不同的表面活性剂、助表面活性剂、表面活性剂与助表面活性剂的质量比（Km）、油相等对微乳形成的影响,从中筛选出最佳微乳制备配方。利用透射电子显微镜和粒径分析仪研究微乳粒子的形态和粒径分布。同时以刺五加叶为原料,采用微乳化技术制备刺五加叶黄酮微乳,以超氧阴离子自由基、羟自由基及1,1-二苯基-2-三硝基苯肼自由基的清除率来考察黄酮微乳的抗氧化能力,以抑菌圈实验研究黄酮微乳的抑菌性能,以刺五加叶黄酮为对照。结果发现,以肉豆蔻酸异丙酯为油相、Tween-80为表面活性剂、无水乙醇为助表面活性剂,且Km＝2时得到的微乳区域面积最大,微乳平均粒径约18.3 nm,高速离心和长时间放置后体系均匀透明、未见分层、稳定性好。抗氧化实验表明,刺五加叶黄酮微乳的抗氧化能力优于刺五加叶黄酮对照。在抑菌圈实验中,黄酮微乳对大肠杆菌、金黄色葡萄球菌、沙门氏菌及荧光假单胞菌的抑菌效果均好于刺五加叶黄酮对照。     

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.