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1.
芝麻素的应用性能研究   总被引:8,自引:0,他引:8  
采用滤纸片法和平板培养法研究了芝麻特征性成分芝麻素的抗菌活性,结果表明,芝麻素对细菌的抑(杀)作用显著,且对细菌的最低抑制浓度(MIC)为0.1%;在实验浓度范围内,芝麻素对真菌基本无抑制作用。另外以过氧化值(POV)为指标研究了芝麻素对大豆色拉油和花生油的抗氧化性能,结果表明,芝麻素具有良好的抗油脂氧化活性。ω(芝麻素)=0.04%在大豆色拉油中的抗氧化活性与ω(BHT)=0.02%相当。  相似文献   

2.
特丁基对苯二酚衍生物的抗氧化性能的研究   总被引:3,自引:0,他引:3  
研究了特丁基对苯二酚(TBHQ)的衍生物(DTBHQ)的抗氧化能力,发现它具有良好的抗氧化性能,其抗氧化能力强于BHA,BHT,TBHQ和VE,在高温下亦有较强的抗氧化能力。DTBHQ对Fe^3 有一定的螯合作用。含4ppmFe^3 的猪油中分别添加0.02%和0.04%的DTBHQ,可使其氧化稳定性提高4.5和7.7倍,与柠檬酸(CA)联合使用,表现出很强的抗氧化协同作用。  相似文献   

3.
大米中黄酮和脂肪酸成分及抗氧化性能的分析   总被引:1,自引:0,他引:1  
对大米中黄酮和脂肪酸成分及抗氧化性能进行了分析。采用超声波法提取大米中的黄酮类化合物,通过光谱分析方法测定黄酮含量,方法的回收率为95.35%~102.8%,相对标准偏差小于0.16%。采用索氏提取法提取了大米中的脂肪油,再进行甲酯化处理,以气相色谱.质谱联用仪进行分析,黑龙江大米、辽宁大米、吉林大米、四川大米、浙江大米及深圳大米中鉴定出的脂肪酸分别占其总检出量的98.95%、92.70%、84.28%、95.80%、93.46%、68.47%,不饱和脂肪酸含量分别占72.93%、69.21%、61.62%、68.62%、68.16%、51.11%。通过流动注射化学发光法分析了大米的抗氧化性能,结果表明,大米具有较强的抗氧化性能。  相似文献   

4.
硫酸铵纯化南果梨果肉多酚氧化酶的研究   总被引:1,自引:0,他引:1  
南果梨果肉中多酚氧化酶经硫酸铵分级沉淀、透析后进行了纯化,比活力提高2.1倍;根据凝胶电泳对其同工酶进行分析,发现其粗酶液中有2条谱带,Rf值分别为0.21、0.26。经35%~85%硫酸铵沉淀透析液纯化透析后同功酶共有5条谱带,Rr值分别为0.21、0.26、0.30、0.39、0.48和0.51。  相似文献   

5.
枸杞多糖酶法提取及其对油脂的抗氧化性能研究   总被引:1,自引:0,他引:1  
研究了提取枸杞多糖的酶种类以及pH值、提取温度、提取时间、酶添加量对枸杞多糖得率的影响,并且确定了最佳提取条件。采用烘箱自氧化法研究了枸杞多糖对油脂的抗氧化性能。实验结果表明,混合酶提取效果最好,最佳提取条件:pH5.0,提取温度50℃,添加0.1%的酶,提取2h;枸杞多糖对油脂有一定的抗氧化性能,而且对动物油的抗氧化性优于植物油。  相似文献   

6.
分别用石油醚、三氯甲烷、乙酸乙酯和无水乙醇依次提取迷迭香成分,并对它们的抗氧化性能进行了一系列测定,发现迷迭香的石油醚、三氯甲烷、乙酸乙酯和乙醇提取物均具有很好的抗氧化作用。加入0.01%时,就表现出明显的抗氧化活性(Pf≥5.62),而且均表现出一定剂量相关性。对合铁离子的猪油也表现出很强的抗氧化性能,添加0.02%的抗氧化剂后,猪油的氧化诱导期仍可达到12h以上。几种提取物与BHA、TBHQ、VE和柠檬酸均没有明显的抗氧化协同作用。  相似文献   

7.
汉麻籽油自氧化及抗氧化性能的研究   总被引:3,自引:0,他引:3  
采用Schaal烘箱法,以过氧化值(POV)为指标,研究温度、时间对汉麻籽油自氧化过程的影响及添加抗氧化剂对汉麻籽油抗氧化性能的影响。结果表明,温度、时间对汉麻籽油的自氧化过程有显著影响,且温度的影响更明显;叔丁基对苯二酚(TBHQ)对汉麻籽油具有较好的抗氧化性能,柠檬酸和异VC对TBHQ与丁基羟基茴香醚(BHA)复配的复合抗氧化剂均表现出较强的协同抗氧化性能,且柠檬酸的协同抗氧化性优于异VC;添加0.02%TBHQ+0.005%BHA+0.01%柠檬酸或0.02%TBHQ+0.005%BHA+0.01%异VC复合抗氧化剂,可使汉麻籽油在20℃下的预贮藏时间从4个月延长至11~13个月。  相似文献   

8.
核桃叶抗氧化作用的研究   总被引:22,自引:1,他引:21  
对核桃叶中抗氧化物质的提取、性能及有效成分进行了较系统的研究。结果表明;核桃叶的乙醇、丙酮1水提取物均有很强的抗氧化作用,其中以丙酮提取物抗氧化作用最强;提取物浓度达0.10%时的抗氧化活性超过0.02%BHT;核桃叶提取物的抗氧化有效成分主要是单宁、黄酮及萜类化合物。  相似文献   

9.
大蒜精油对食用油脂的抗氧化特性   总被引:35,自引:3,他引:35  
以过氧化值(POV)为指标研究了大蒜精油对花生油的抗氧化性能。结果表明:大蒜精油对花生油具有较强的抗氧化作用,且具有剂量效应关系;添加了大蒜精油的花生油应尽量贮存于低温条件下;VC、柠檬酸、酒石酸对大蒜精油的抗氧化作用均有协同增效作用;大蒜精油与合成抗氧化剂混合使用时,其抗氧化能力均好于只添加单一抗氧化剂的效果;使用0.2%大蒜精油和0.04%大蒜精油+0.005%PG为花生油的抗氧化剂时,可使花生油在20℃下的贷架寿命由4.2个月延长至24.3个月和14.1个月。  相似文献   

10.
红树莓叶片中黄酮类物质提取及抗氧化性的研究   总被引:20,自引:0,他引:20  
以小浆果果树红树毒叶片为实验材料,利用分光光度法测定其总黄酮含量,并采用烘箱贮存法研究了不同添加量红树毒叶片提取物粗黄酮在猪油中的抗氧化性。结果表明:鲜样中红树毒叶片总黄酮含量是278.73mg/100g,干样中是533.71mg/100g;红树毒叶片提取物粗黄酮对猪油有一定的抗氧化作用,并随添加量的增加而增强;增效剂以(柠檬酸)对红树毒叶片提取物粗黄酮无增效作用,而Vc具有一定的增效作用。抗氧化活性顺序为:0.02%槲皮素>0.02%PG>0.02%BHT>0.4%粗黄酮>0.05%粗黄酮 0.05%Vc>0.2%粗黄酮>0.1%粗黄酮>0.05%粗黄酮>0.02%粗黄酮>0.05%粗黄酮 0.05%CA>对照。  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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