槲皮万寿菊素纳米乳液的制备和性质表征:乳化剂类型、pH、离子强度、热处理的影响

分别以α-乳白蛋白、β-乳球蛋白和乳铁蛋白为乳化剂,食品级中碳链脂肪酸甘油三酯为油相,以槲皮万寿菊素为芯材,采用二级高压均质法制备槲皮万寿菊素水包油型纳米乳液。通过测定乳液粒径大小、多分散指数、Zeta电位、浊度来对比三种乳化剂的乳化效果,研究不同pH、离子强度、热处理对乳液理化性质的影响,利用分光光度法测定纳米乳液对槲皮万寿菊素的包埋率,并采用Lu Mi Sizer稳定性分析仪对样品稳定性进行分析检测。结果表明,乳化剂种类对乳液粒径大小、分布情况有显著影响,以α-乳白蛋白为乳化剂稳定的槲皮万寿菊素纳米乳液平均粒径最小,为285.3±3.3 nm,多分散指数为0.19±0.03,包埋率约96.8%。在不同pH、离子强度和热处理条件下,以α-乳白蛋白为乳化剂稳定的槲皮万寿菊素纳米乳液具有最优的稳定性。     

OSA变性淀粉的乳化特性及其对纳米乳液构建影响的研究

研究生物大分子辛烯基琥珀酸淀粉(OSA)的乳化特性,并以其为乳化剂构建负载番茄红素的稳定纳米乳液体系。研究结果表明:溶解温度70℃,淀粉浓度为30%(w/w)时,OSA变性淀粉的乳化性能最佳。以其为乳化剂,当油相(中链甘油三酯,MCT)中番茄红素的质量浓度为0.1%(w/w),油水比1∶9时,通过高压均质得到的纳米乳液粒径120 nm,番茄红素负载率63%,经过一个月的储藏后,乳液粒径增加到160 nm,增长幅度小于34%,性状稳定,没有油相析出,表明OSA变性淀粉适合作为构建安全稳定纳米乳液的乳化剂。     

肉桂精油乳液的制备及抑菌性

肉桂精油具有抑菌杀菌、抗氧化等功效,但因其水溶性差、易挥发、稳定性差,限制了应用。将肉桂精油溶解于中链脂肪酸,以司班20与吐温80为乳化剂,制备水包油型乳液。通过改变肉桂精油的质量分数（0%~2.5%）,可得粒径分布在50~280 nm乳液。离心实验发现,该乳液稳定性好,且适宜于在温度低于40 ℃条件下使用。在25 ℃下储藏10 d,乳液的粒径和分散系数几乎不变。此外,利用比浊法测定不同粒径的乳液抑菌效果发现,粒径为150 nm的肉桂精油乳液对大肠杆菌和金黄色葡萄球菌的抑制效果最好。     

高压微射流制备橙皮精油纳米乳液影响因素研究

本文探讨了乳化剂类型、浓度和均质条件(压力和均质次数)对橙皮精油纳米乳液平均粒径(mean droplet diameter,MDD)、浊度以及贮藏稳定性的影响。采用四种乳化剂(皂树苷,QS;变性淀粉,MS;乳清分离蛋白,WPI;十二烷基硫酸钠,SDS),经高压微射流经不同均质压力和均质次数制备橙皮精油纳米乳液。结果表明,在一定范围,随着乳化剂浓度增加,MDD会逐渐减小,而SDS、QS、WPI和MS合适的浓度分别为2%、4%、4%和8%(w/w)。随着均质压力和均质次数增加,纳米乳液MDD和浊度都呈现较相似的减小趋势,在压力和次数分别增加到22000 psi和4次时,四种纳米乳液粒径可小于150 nm。研究发现,均质压力与MDD近似指数关系,乳液的相黏度比也会影响其MDD。贮藏实验表明,经25 ℃贮藏21 d,四种纳米乳液MDD基本稳定。     

肉桂精油的超临界CO2萃取工艺及成分研究

研究了超临界CO2萃取肉桂精油时压力、温度、萃取时间等因素对提取效果的影响,通过正交实验确定最佳的萃取工艺条件为萃取压力15MPa,温度40℃,时间2h,此条件下肉桂精油的产率为3.69%.用GC/MS测定超临界CO2萃取的肉桂精油,鉴定出43种成分,主要有反式肉桂醛、3-甲氧基肉桂醛、α-咕巴烯、δ-杜松烯、α-蛇麻烯、乙酸肉桂酯等,其中反式肉桂醛含量最高,达到30.97%.     

油相浓度对姜黄素纳米乳液稳定性的影响

以中链甘油三酯为油相,卵磷脂为乳化剂,采用高压均质技术制备出含不同油相浓度的姜黄素纳米乳液,于4、25和55℃条件下贮藏30 d,研究不同油相浓度对姜黄素纳米乳液稳定性的影响。结果表明:油相浓度较低(5%、10%)时,姜黄素纳米乳液具有较高的稳定性,姜黄素保留率分别达到48.50%和48.99%,粒径增加了0.79%和15.78%;且4℃贮藏时,其理化稳定性表现最好,30 d后姜黄素损失率仅为14.98%。     

不同乳化剂制备β-胡萝卜素纳米乳液研究

选择吐温20(TW)、十聚甘油单月桂酸酯(DML)、辛烯基琥珀酸淀粉酯(OSS)、乳清分离蛋白(WPI)四种乳化剂(1%,w/w),采用高压均质法制备β-胡萝卜素纳米乳液(0.03%,w/w).利用激光粒度仪分析纳米乳液的粒径大小与分布,Turbiscan浓缩体系稳定性分析仪监测纳米乳液稳定性变化趋势,HPLC法检测纳米乳液中β-胡萝卜素的含量.研究结果显示,纳米乳液粒径主要分布在115.0～303.0nm,多分散系数0.09～0.30,含有TW、DML的纳米乳液粒径显著小于含有OSS、WPI的纳米乳液(P＜0.05);储藏实验中,55℃下纳米乳液粒径增大显著,4℃下粒径变化不显著(P＞0.05);含有OSS的纳米乳液中β-胡萝卜素降解最快,55℃储藏12d、4℃储藏28d后残留率分别仅为22.88%和26.23%,而含有WPI的纳米乳液中β-胡萝卜素降解最慢,在相同条件下储藏,残留率分别为72.23%和62.08%.     

精油纳米乳液对禾谷镰刀菌的抑制作用

禾谷镰刀菌及其产生的真菌毒素会对谷物的质量与安全造成严重危害,开发绿色抗真菌剂是保障食品安全的需要。采用高速搅拌结合高压均质的方法制备4种植物精油纳米乳液,考察其对禾谷镰刀菌生长、脱氧雪腐镰刀菌烯醇(deoxynivalenol, DON)及其衍生物产生的抑制作用。结果表明,乳液各组分质量分数分别为1%卵磷脂、8%油相[丁香油及山苍子油为纯精油,肉桂油和牛至油为精油与中链甘油三酯(medium chain triglycerides, MCT)以1∶1比例混合]及91%的去离子水,丁香油乳液、肉桂油/MCT乳液、牛至油/MCT乳液和山苍子油乳液皆为单峰分布,平均粒径分别为116.9、168.5、206.0和203.9 nm,4种乳液在21 d内展现出较好的储存稳定性;4种乳液均对禾谷镰刀菌生长和真菌毒素的产生具有一定的抑制作用,其中40 mg/g的肉桂油/MCT乳液对禾谷镰刀菌菌丝抑制率达66.2%,1.5 mg/g的质量分数下对真菌生物量的抑制率可达98.9%,0.3 mg/g的质量分数对DON和15-乙酰基脱氧雪腐镰刀菌烯醇(15-acetyl-deoxynivalenol, 15ADON)的抑制效果即可达98.8%和96.6%。     

肉桂皮精油提取工艺的优化及成分分析

为了综合利用肉桂皮,对肉桂皮精油快速溶剂萃取工艺进行优化。以肉桂皮为材料,运用中心组合Box-Behnken设计方案获得萃取工艺的时间、温度和萃取次数等因素对精油得率的影响,对影响快速溶剂萃取精油的主要因素及其相互作用进行探讨,并结合GC-MS分析肉桂精油的化学成分,得到的优化工艺参数为:萃取时间327s,萃取温度92℃,萃取2次,理论提取得率为1.168%,实际提取率为1.133%,比理论值低0.035%。气相色谱-质谱分析鉴定了48种化合物,应用峰面积归一法计算各组分的相对百分含量,已鉴定精油主要成分为反式-肉桂醛(34.11%)、顺式-肉桂醛(4.18%)、肉桂酸(19.96%)、α-蒎烯(3.90%)、α-紫罗烯(2.64%)、邻甲氧基肉桂醛(1.43%)、α-依兰烯(2.45%)、α-毕橙茄醇(1.27%)、愈创木烯(1.79%)等。所得桂皮精油呈淡黄色,具有肉桂特征香气,折光率为1.6094,酸值为4.5。     

肉桂精油纳米乳液的抑菌性和稳定性研究

为改善精油的稳定性及抑菌性能,利用羟丙基-β-环糊精(HPCD)与酪蛋白酸钠(SC)共同乳化肉桂精油(CEO)制备纳米乳液,探究乳液的粒径、抑菌性的变化及乳液在不同温度下的储存稳定性。结果表明：相比单独使用酪蛋白酸钠稳定的乳液,HPCD的添加可以显著降低酪蛋白酸钠-精油乳液的粒径及PDI值。1%酪蛋白酸钠和3%HPCD共同稳定的肉桂精油纳米乳液对大肠杆菌和金黄色葡萄球菌的生长有良好的抑制作用,当精油添加量为10%时,大肠杆菌浓度降低了2.62 Lg(CFU/mL),金黄色葡萄球菌浓度降低了0.85 Lg(CFU/mL);乳液在4、25和40℃下储存过程中的粒径、乳化指数的变化表明1%酪蛋白酸钠和3%HPCD共同乳化的肉桂精油纳米乳液具备良好的稳定性。仅当精油浓度10%时,乳液的粒径、乳化指数随着储藏时间的延长有所增加,但荧光显微镜显示乳液中油滴仍然分布相对均匀。     

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