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1.
采用滴加水法制备甘油解猪油微乳液,考察不同表面活性剂、助表面活性剂、制备温度及制备方式等因素对微乳液形成过程中最大增容水量的影响,并鉴别该微乳液的类型及测定其氧化稳定性.结果表明,以吐温80为表面活性剂,无水乙醇为助表面活性剂,以甘油解猪油为油相,在60℃的条件下通过磁力搅拌的方式制得的微乳液增溶效果最好,该微乳液呈油...  相似文献   

2.
研究了将共轭亚油酸乙酯作为营养强化剂,按不同的量添加到纯牛乳中对产品感官品质的影响,并对产品的贮藏氧化稳定性进行了研究。结果表明:共轭亚油酸乙酯添加量为0.1%时能赋予产品细滑香浓的口感;共轭亚油酸乙酯在牛乳中具有良好的稳定性;添加VE、VC不能起到抗氧化作用。  相似文献   

3.
本文研究了共轭亚油酸乙酯和共轭亚油酸三甘酯的氧化稳定性,并与富含不饱和脂肪酸的红花籽油比较,探讨了变价金属离子和抗氧化剂对共轭亚油酸乙酯和共轭亚油酸三甘酯的氧化稳定性的影响。结果表明共轭亚油酸三甘酯的氧化稳定性优于共轭亚油酸乙酯的氧化稳定性;加入0.02%VE可明显提高它们的氧化稳定性,而0.02%三氯化铁则减弱了它们的氧化稳定性;VC在共轭亚油酸酯类的油状体系中对抗氧化剂维生素E没有增效作用。  相似文献   

4.
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。  相似文献   

5.
以猕猴桃籽油为原料,采用拟三元相图法制备微乳液并研究其稳定性,以推测货架期。在固定表面活性剂为1,2丙二醇、制备温度为30℃的条件下,分别讨论猕猴桃籽油与肉豆蔻酸异丙酯(IPM)、混合表面活性剂吐温80与司盘80及表面活性剂与助表面活性剂(Km值)的比值对形成微乳液面积区大小的影响,通过计算并比较拟三元相图微乳液区面积大小确定各因素的配比;并以过氧化值为稳定性评价指标,采用Schaal烘箱加速氧化法探讨贮藏温度对猕猴桃籽油微乳液氧化稳定性的影响,根据Arrhenius经验公式推导出货架期模型,对猕猴桃籽油微乳液货架期进行科学预测。结果表明,制备具有最大含水量的猕猴桃籽油微乳液的工艺组合为:猕猴桃籽油与IPM质量比11、吐温80与司盘80质量比21、表面活性剂与助表面活性剂质量比31,该条件下油相占体系的24.3%、增水量为19.29%,微乳液的类型为油包水型,并具有良好的离心稳定性;猕猴桃籽油氧化一级反应回归方程为c=0.041 7e~(0.001 1 t),氧化反应动力模型为k=652.3e-(32 763.8)/(RT),该模型预测猕猴桃籽油微乳液在25℃货架期为1 491.53h。  相似文献   

6.
将表面活性剂复配,制备了油包水型紫甘薯色素微乳液。以最大增溶水相质量为指标,通过绘制三元相图确定微乳体系中混合表面活性剂与油相的最佳比例。在此基础上,研究了不同助表面活性剂及其浓度、色素含量、水相p H对最大增溶水相质量的影响。采用电导率法鉴别微乳液的类型。结果表明,将表面活性剂复配后更有利于形成微乳液的形成。不同助表面活性剂及它的浓度都能影响最大增溶水相质量。制备的油包水型微乳液在贮藏期间稳定性良好,未出现分层现象。  相似文献   

7.
本文研究并制备了聚氨酯型金属铬(Ⅲ)络合物微乳液。优选了复配乳化剂的种类、配比及助表面活性剂的种类;讨论了复配乳化剂和助表面活性剂的用量对乳液稳定性与粒径的影响。通过纳米粒度测定仪、透射电镜对最优条件下的微乳液进行了表征。  相似文献   

8.
共轭亚油酸的微乳及其性质研究   总被引:1,自引:0,他引:1  
制备了共轭亚油酸/EL-35和EL-10/乙醇/水体系的O/W型微乳液.考察了温度、防腐剂和pH对微乳液区域的影响;动态光散射测定了微乳液的粒径;利用粘度计测定不同水含量的微乳液的粘度变化来观察微乳液流变性:对O/W、W/O、B.C.中的共轭亚油酸的微乳液和共轭亚油酸乙醇溶液进行了光稳定性研究,还分析了温度和pH对微乳液和乙醇溶液中共轭亚油酸稳定性的影响.结果表明,温度升高,防腐剂苯甲酸钠浓度变大和pH降低使微乳区稍有减小;微乳液粒径在制备三个月后仍保持在80~90nm之间;共轭亚油酸对光热和酸都比较敏感,但同环境条件下,O/W型微乳液中的共轭亚油酸比较稳定.  相似文献   

9.
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。  相似文献   

10.
本文以肉豆蔻酸异丙酯为原料,筛选出肉豆蔻酸异丙酯空白微乳的最佳配方。首先采用伪三元相图法,以微乳区面积为指标,筛选出表面活性剂和助表面活性剂;探究表面活性剂与助表面活性剂质量之比Km值与亲水亲油平衡值(HLB值)对微乳形成的影响,然后以离心和染色实验来判断微乳的稳定性和构型。结果表明:当以肉豆蔻酸异丙酯作为油相,吐温80复配司盘80作为复合表面活性剂,无水乙醇为助表面活性剂(表面活性剂∶助表面活性剂∶IPM=4∶2∶4),且Km=2∶1,HLB=7.5时,形成的微乳液稳定性最好。此条件下,油包水型微乳的最大载水量为15.3%。因此可以说明伪三元相图法制备肉豆蔻酸异丙酯方法方便可行。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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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.  相似文献   

18.
<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  相似文献   

19.
《印刷工业》2014,(11):95-95
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%.  相似文献   

20.
《印刷工业》2014,(8):103-103
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  相似文献   

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