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1.
叶子花红色素的提取及其稳定性研究   总被引:4,自引:0,他引:4  
以叶子花苞叶为原料提取红色素,经正交试验选择最佳提取条件,并对光、温度、pH值、氧化还原介质、6种金属离子和4种食品添加剂对色素稳定性的影响进行了研究。结果表明,叶子花红色素为水溶性花青素的花色苷,在可见光区的最大吸收波长λmax=541nm。最佳提取条件为:以5%乙醇为提取剂,配料比为1:15,25℃下保温浸提3次,每次1h.该色素在70℃以下稳定性较好,对光的耐受性较差:色素在酸性条件下稳定,耐还原性强,但耐氧化性较差。6种金属离子中,Cu^2+、Zn^2+、Fe^3+对色素有明显的破坏作用,而Mn^2+、Mg^2+、Al^3+对色素稳定性较好,并有不同程度的护色作用。葡萄糖、NaCl、VC、苯甲酸钠对色素无不良影响。  相似文献   

2.
樟树熟果红色素提取工艺及稳定性研究   总被引:6,自引:2,他引:4  
为开发利用樟树果实的丰富资源,增加其经济附加值及为寻找新的天然食品着色剂提供依据,从提取工艺条件、pH、温度、时间等方面对樟树熟果红色素的提取方法及其稳定性进行了研究.结果表明,最佳的提取工艺条件为料液比1:25,pH1,提取温度60℃,提取时间90min;该色素在可见区最大吸收波长为509nm;该色素受pH值影响较大,在pH1时的A509nm较大,色泽鲜艳,对温度不稳定.在pH5时的A509nm较小,但对温度较稳定,在pH>9时色素变色;色素对金属离子的稳定性较高,Fe^3+使色素溶液变色,Cu^2+对色素有增色效果,但加速了色素的降解,Ca^2+对色素有一定的降解作用,Mg^2+、Na^+对色素无不良影响;食品添加剂VC、柠檬酸对色素有一定增色效果,苯甲酸钠对色素有降色效果,蔗糖和淀粉对色素的影响不大;氧化还原剂对色素有破坏作用.  相似文献   

3.
草莓色素的提取及稳定性的研究   总被引:8,自引:0,他引:8  
对从草莓果实中提取红色素的方法和条件及该色素的稳定性进行了研究,结果表明最佳的提取工艺为:1.5mol/L的HCl溶液和97.5%的乙醇以体积分数1:9为浸提剂,料液比(质量浓度g/mL)为1:12,提取温度为40℃,提取时间为5h,pH对色素的影响明显,在酸性条件下该红色素较稳定。金属离子Na^ 、Ca^2 、Mg^2 、Zn^2 、K^ 对色素无不良影响,而Fe^3 、Al^3 、Cu^2 、Fe^2 对色素则有明显影响;草莓色素有一定的耐糖性;VC、H2O2、Na2SO3对色素有严重的破坏作用,低浓度的则有明显的降解作用。  相似文献   

4.
红花继木叶红色素的提取及性质研究   总被引:7,自引:1,他引:6  
研究了红花继木叶色素的提取条件和理化性质,结果表明,用料液比1:40、pHl的80%乙醇作提取剂、在80℃恒温浸提40min,提取效率较好。红花继木叶色素属花青素类色素,pH值对色素影响明显,60℃以内比较稳定。光照能加快色素降解。金属离子Na^+、Ca^2+、Al^3+、Cu^2+、Zn^2+对色素色泽无影响,而Fe^3+、Pb^2+有不良影响。色素的抗氧化能力较差而耐还原性能较好。蔗糖、葡葡糖和盐等添加剂对色素无影响。  相似文献   

5.
紫色甘薯茎叶色素提取及稳定性的研究   总被引:1,自引:0,他引:1  
杨萍 《粮油加工》2010,(2):76-79
本文对紫色甘薯茎叶中色素的提取条件及稳定性的研究结果表明:用体积分数为95%乙醇80mL,在50℃恒温下浸取30h,提取效率较好。pH值对色素的色泽影响明显,在酸性条件下色泽稳定,适宜低温储藏;光照加快色素分解,宜在黑暗处保藏;金属离子Ca^2+、Mg^2+、Zn^2+、Cu^2+、Na^+对色素稳定性几乎没影响,Fe^3+使色素的吸光度值明显减少,溶液的颜色逐渐变成深黄色,Sn^4+使溶液的颜色逐渐加深,吸光度值变大;因此在甘薯茎叶的加工和使用过程中要避免与Sn^4+、Fe^3+接触。蔗糖、山梨酸钾和维生素C对色素的稳定性影响较小。  相似文献   

6.
薯莨色素的提取以及稳定性研究   总被引:2,自引:0,他引:2  
张淑云  王玉杰  陈国强 《染整技术》2010,32(3):36-38,55
本文对从薯莨中提取薯莨色素的方法进行了优选,得到了提取的最佳工艺:70%丙酮溶液为提取剂,溶质和溶剂比1:5,60℃水浴中浸提3h。并且对提取的薯莨色素的pH、光照、温度和金属离子对其稳定性的影响进行了研究,结果表明,薯莨色素较长时间的光照对其稳定性有影响,适宜避光保存;在70℃以下、酸碱为中性的条件下性质稳定;Fe^2+和Zn^2+对其稳定性的影响不大,但是Ti^4+对其影响很大。  相似文献   

7.
本文对从薯莨中提取薯莨色素的方法进行了优选,得到了提取的最佳工艺:70%丙酮溶液为提取剂,溶质和溶剂比1:5,60℃水浴中浸提3h。并且对提取的薯莨色素的pH、光照、温度和金属离子对其稳定性的影响进行了研究,结果表明,薯莨色素较长时间的光照对其稳定性有影响,适宜避光保存;在70℃以下、酸碱为中性的条件下性质稳定;Fe^2+和Zn^2+对其稳定性的影响不大,但是Ti^4+对其影响很大。  相似文献   

8.
张钟  柳红 《饮料工业》2006,9(7):11-15
运用超声波辅助技术提取黑糯玉米芯色素,研究了pH、光照、温度、氧化剂、还原刺、金属离子、共存物质对黑糯玉米芯色素稳定性的影响,并与相同条件下常规提取的黑糯王米芯色素进行比较。结果表明:光照、温度对两种方法提取出的色素无显著性影响;过氧化氢、亚硫酸钠、维生素C溶液对黑糯玉米芯色素影响较大;金属离子中的Fe^2+、Fe^2+、Sn^2+对黑糯玉米芯色素稳定性影响较大,食品中常用的葡萄糖、蔗糖对色素有一定的降解作用;防腐剂苯甲酸钠对色素有一定的降解作用,且浓度越大,影响越大。柠檬酸、苹果酸、可溶性淀粉对色素溶液有增色作用;超声波辅助提取的色素和常规法提取的色素的稳定性基本一致。  相似文献   

9.
小米黄色素的研究Ⅱ-提取工艺及稳定性   总被引:7,自引:3,他引:4  
开发研究了小米黄色素,对其提取工艺条件及几种提取剂进行了筛选,确定了最佳提取工艺条件为:95%乙醇为最佳提取剂;v(乙醇):m(小米)=3:1,室温提取3~4次,每次2~4h。研究了光、热、氧化剂、还原剂、金属离子以及几种常用食品添加剂对小米黄色素稳定性的影响,结果表明:该色素溶液的最大吸收波长为445nm;具有一定的耐热性、耐还原性和耐氧化性;但耐光性差,宜避光保存;Fe^3+对色素有破坏作用,K^+、Na^2+、Ca^2+、Mg^2+、Zn^2+、Cu^2+、Fe^2+无不良影响;可与Vc、蔗糖和柠檬酸等食品添加剂调和使用。  相似文献   

10.
建立了海南野生仙人掌果实中红色素提取的最佳工艺条件,并对提取的红色素的稳定性进行了研究,为利用仙人掌果开发天然色素提供理论依据。红色素的提取工艺条件为:70%的乙醇溶液作为溶剂,提取温度为50℃,提取体系的料液比为1:20,提取pH5.0,提取时间1h。稳定性实验结果表明:仙人掌果红色素在pH3-5时红色素较稳定,色素随着光照的天数、氧化剂、还原剂浓度增加稳定性变差,红色素对金属离子Na^+、Mg^2+较稳定,而对Zn^2+、Sn^2+、Fe^3+、Cu^2+、Pb^2+较不稳定。  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.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

16.
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   

17.
18.
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   

19.
The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.  相似文献   

20.
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