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1.
采用活性炭脱色,选取时间、温度、活性炭用量3个因素进行正交实验,用脱色率和多糖含量作为考察指标。采用三氯乙酸法和Sevage法去除蛋白质,主要研究其浓度与体积比对蛋白质去除率和多糖损失率的影响。结果表明:40℃、40min、活性炭用量为1.0%时去除色素效果最好,脱色率为21.98%,多糖保留率为94.09%。薯蔓多糖溶液与5%TCA溶液体积比为1:2时,去除蛋白质效果较好;Sevage(氯仿:正丁醇=4:1)溶液与薯蔓多糖溶液体积比为1:1时,去除蛋白质效果较好。  相似文献   

2.
为了更好的开发利用香菇资源,本研究以香菇培养基废弃物为材料、多糖为研究对象,通过对比分析和L9(3^4)正交试验设计等研究方法,重点考察不同超声功率、料液比、超声时间对香菇培养基废弃物中多糖提取率的影响。结果表明,最佳提取工艺条件为超声时间45min,料液比1:30,超声功率300W,多糖提取率平均可达3.46%。  相似文献   

3.
采用常用的正交试验法[L16(4^5)]和单因素试验法相结合的方法优选了提取仙草色素的方法,并对该提取工艺的条件进行了初步探索。试验结果表明,各因素对仙草色素提取效果的影响程度依次为:浸提酸度〉原料粒度〉浸提温度〉浸提剂;最佳提取工艺条件是:浸提酸度pH=14,原料粒度为40目,浸提温度为室温(25℃),浸提剂为水,浸提时间为90min;此时色素的提取率可达12.44%。另外,微波或超声波对仙草色素的提取有明显促进作用。  相似文献   

4.
龙井绿茶茶多酚提取工艺研究   总被引:5,自引:0,他引:5  
为了提高茶多酚的得率和纯度,以龙井绿茶为原料,对茶多酚进行乙醇溶液提取、超声波和微波辅助提取。醇提的最佳条件为乙醇浓度50%,浸提4次,每次45min,温度为70℃,液固比为20:1,最大浸提率为24.45%。微波辅助提取最佳条件为预浸30min,乙醇浓度40%,微波解冻档浸提4min,浸提2次,液固比为40:1,最大浸提率为24.70%。超声波辅助浸提最佳条件为乙醇浓度80%,浸提温度50℃,浸提时间25min,浸提2次,液固比为14:1,最大浸提率为24.72%。结果表明:微波与超声波提取率稍高于醇提,但三者差别不大。  相似文献   

5.
正交试验法优选坛紫菜多糖的提取工艺   总被引:2,自引:0,他引:2  
目的:对常规法提取紫菜多糖的工艺进行优化;方法:L16(4^4)正交试验及方差分析;结果:影响紫菜多糖热水提取的主要因素为醇沉浓度,其次是浸提时间,再次是浸提温度和料液比;结论:常规法提取紫菜多糖的优选方案为浸提温度80℃、浸提时间1.5h、料液比1:20、醇沉浓度90%。  相似文献   

6.
以苹果渣为原料。对用微波辅助提取、提取液脱色、乙醇沉析获得果胶的关键提取条件进行了研究。通过L9(3^4)正交试验,得到了在微波辐射功率为250w时果胶提取的最佳工艺条件:料液比1:40,提取时间35min,pH=1.3,提取温度65℃,此时,果胶的提取率可以达到10.61%。效果很佳。  相似文献   

7.
以羊肺为原料,采用微波辅助法及盐解、沉淀剂除蛋白质的方法提取和分离肝素钠。在单因素试验基础上,设计L9(3^4)正交试验确定最佳提取工艺条件。结果表明,最佳提取工艺为料液比1:15(g:mL),微波作用时间180S,微波功率480W,沉淀剂用量为0-8%,此条件下肝素钠得率为294.78mg/kg。  相似文献   

8.
菊花绿茶复合饮料的研制   总被引:1,自引:0,他引:1  
以绿茶、菊花为主要原料,研究了菊花茶饮料加工工艺中的最佳浸提方法和条件,确定了饮料的最佳调配比例。结果表明,采用微波辅助水浴法浸提得到的浸提液品质较常规水浴法的好,微波辅助水浴法浸提绿茶的最佳工艺条件为:茶水比1∶100、pH5、微波功率为400W条件下处理4min、90℃水浴锅中浸提10min;菊花浸提最佳工艺条件为:料水比1∶180、微波功率为175W条件下处理10min、80℃水浴锅中浸提15min。饮料最佳调配比例为绿茶汁40%、菊花汁50%、白砂糖2%、柠檬酸0.02%。  相似文献   

9.
超声波辅助提取茶鲜叶中茶多糖实验研究   总被引:1,自引:0,他引:1  
本文研究了超声波辅助法提取茶树鲜叶中多糖的工艺。通过正交试验设计L9(3^4)提取多糖,以蒽酮-硫酸法测定多糖含量,得出优化工艺的条件为:固液比为1:10,浸提时间为60min、浸提温度为70℃、提取次数为3次,在此条件下茶粗多糖提取率为5.155%。  相似文献   

10.
梁引库  吴三桥 《食品科技》2012,(12):166-169
目的:研究脱色和脱蛋白工艺中不同条件对黄精中多糖纯化效果的影响,得出黄精多糖的最佳脱色和脱蛋白工艺。方法:通过用双氧水和活性炭对黄精多糖进行脱色,在此基础上研究浓度差异对脱色效果的影响,确定最佳脱色工艺。采用Sevage法和TCA法对黄精多糖进行脱蛋白,研究不同条件对脱蛋白效果的影响。结果:双氧水法为黄精多糖的最佳脱色方法,其最佳脱色浓度为1%;Sevage法为黄精多糖的最佳脱蛋白方法,其最佳比例为氯仿:正丁醇为6:1。  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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17.
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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