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1.
尿素包合法纯化红花籽油工艺研究   总被引:1,自引:0,他引:1  
介绍了以尿素包合法纯化红花籽油中亚油酸的方法.对多不饱和脂肪酸的制备及尿素包合法纯化其中亚油酸的工艺进行了研究,结果表明,尿素:甲醇浓度为0.3(w/v)、温度10℃、时间为24h、(尿素+甲醇):原料脂肪酸的质量比为1:1时,富集效果最好,纯化后脂肪酸的纯度和得率可分别达到93%和90%以上.  相似文献   

2.
以亚油酸含量81.74%的红花油为原料,采用先碱性醇解,后尿素包合的方法。从红花油中富集亚油酸。通过正交试验,确定了尿素一次包合法富集高纯度亚油酸甲酯的最佳工艺条件:混合脂肪酸甲酯:尿素:甲醇为1.04:1:4(W/W/V),包合温度-10℃,包合时间24h,亚油酸甲酯得率72.95%,纯度99.27%。  相似文献   

3.
尿素包合法纯化共轭亚油酸条件的优化研究   总被引:3,自引:0,他引:3  
采用尿素包合法对纯度在70%的共轭亚油酸(CLA)进行了提纯研究。共轭亚油酸在甲醇与尿素形成的体系中70℃加热回流2h,其中的饱和脂肪酸和单不饱和脂肪酸与尿素形成复合物析出,从而可以使共轭亚油酸得到纯化。研究发现,尿素包合共轭亚油酸的最佳工艺条件为:共轭亚油酸,尿素/甲醇=1:2.5:8,包合温度为-15℃,包合时间为6h,得到的共轭亚油酸经过三氟化硼-甲醇溶液衍生化后,用气相色谱进行检测纯度可达93,6%,基本实现了共轭亚油酸的分离纯化。  相似文献   

4.
葵花油中不饱和脂肪酸的富集工艺研究   总被引:4,自引:0,他引:4  
葵花油中富含不饱和脂肪酸,尤其是亚油酸。采用尿素包合法对葵花同中的不饱和脂肪酸进行富集,一次富集产品使不饱和脂肪酸含量由71.3%提高到95.6%,亚油酸含量从71.3%提高到92.7%,从而使脂肪酸的质量有了进一步提高。从研究过程中得到最佳实验条件为:以甲醇作溶剂,脂肪酸,尿素,甲醇比为1:3:8,包和温度为-10℃,时间为12h.  相似文献   

5.
本文以葵花籽油为原料,以制备多不饱和共轭亚油酸及尿素包合法纯化亚油酸的工艺进行了研究,重点考察了皂化温度、稀硫酸的浓度、离心转速、离心时间、95%乙醇与尿素配比(v/w)、尿素与脂肪酸配比(w/w)以及尿素包合时间对富集效率的影响。结果表明:最佳分离纯化工艺条件为皂化温度80℃、稀硫酸浓度20%、离心转速3 000r/min、离心时间10min、95%乙醇尿素比为3∶1、尿素脂肪酸比为1.5∶1和尿素包合时间12h。  相似文献   

6.
离心对尿素包合法富集玉米油亚油酸效果的影响   总被引:1,自引:1,他引:0  
对北方室温条件下,增加离心步骤对尿素包合法富集玉米油亚油酸的效果进行了探讨,并对尿素包合法富集亚油酸工艺进行了研究.结果表明:离心可以使混合脂肪酸中亚油酸含量提高9.65%,以离心后的混合脂肪酸为原料,经尿素包合,富集后的亚油酸含量达93.99%,与未经离心的混合脂肪酸含量相比,提高了12.29%.同时研究了用80%-100%不同浓度的乙醇溶解尿素,进行尿素包合对亚油酸的影响,结果表明:亚油酸的碘值和回收率差异不显著.  相似文献   

7.
采用气相色谱及气相色谱-质谱定性、定量分析燕麦麸油及尿素包合法富集后的不饱和脂肪酸中的脂肪酸相对含量.结果表明,富集后的不饱和脂肪酸中油酸26.07%、亚油酸67.10%、亚麻酸1.37%、二十碳三烯酸2.47%.其中经过尿素包合法富集后的亚油酸含量达67.10%,远高于燕麦麸油中的35.80%,说明尿素包合法富集不饱和脂肪酸的效果好.  相似文献   

8.
亚油酸及共轭亚油酸异构体纯化技术优化   总被引:2,自引:0,他引:2  
以红花籽油制备的亚油酸样品和共轭亚油酸样品为原料,采用溶剂低温结晶法和尿素包合法对共轭亚油酸与亚油酸进行分离纯化,结果表明,与溶剂结晶法相比,尿素包合法对共轭亚油酸和亚油酸有更好的纯化效果.正交实验得到的尿素包合法最佳工艺条件为:m(共轭亚油酸):m(尿素)=1:3,m(尿素):V(乙醇)=1:5,4℃放置24 h得到含量95.17%的共轭亚油酸;m(亚油酸样品):m(尿素)=1:3,m(尿素):V(乙醇)=1:5,-10 ℃放置24 h得到含量99.93%的亚油酸.  相似文献   

9.
尿素包合法富集松油酸的研究   总被引:1,自引:0,他引:1  
采用尿素包合法对超临界CO2萃取的红松子油中的松油酸进行富集研究。尿素包合法富集红松子油中的松油酸的最佳工艺条件为脂肪酸:尿素:乙醇为1:3.5:8(W:W:V),包合温度为5℃,包合时间为10h,多不饱和脂肪酸得率为11.69%,松油酸含量从14.80%提高到85.92%.  相似文献   

10.
从酸菜中分离出的一株植物乳杆菌Lactobacillus plantarum诱导培养,在氮气保护下利用休止细胞催化制备共轭亚油酸。0.1M磷酸钠缓冲液、pH值7.0、亚油酸浓度2%(w/v)、细胞浓度20%(w/v)、30℃。反应64h,共轭亚油酸产量最高。c9,t11/t9,c11—CLA异构体在产物脂肪酸中的比例为30%。  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   

15.
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H2O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.  相似文献   

16.
17.
A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.  相似文献   

18.
19.
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   

20.
<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   

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