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纯种强化发酵细菌型豆豉研究 总被引:1,自引:0,他引:1
研究以纯种强化发酵细菌型豆豉为基础,以氨基酸态氮为指标,通过正交试验确定了前发酵条件对豆豉感官评价的影响.结果表明,枯草芽孢杆菌RH3519和BJ1-3最佳前发酵条件为泡豆水pH值为8.0,水温40℃,泡豆12h,接种量1.5%,发酵温度37℃,发酵3d.其中RH3519发酵的豆豉,氨基酸态氮及总酸含量分别为1.12g/100g、0.27g/100g,显著高于枯草芽孢杆菌BJ1-3和自然发酵的豆豉,且色泽与风味最佳.经初步工业放大试验显示,RH3519发酵的豆豉色泽更接近于自然发酵的豆豉,拉丝丰富,豉香诱人,且质地均匀,酱香浓郁,可作为工业纯种强化发酵生产豆豉的优良候选菌株. 相似文献
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《食品科学》2020,(2)
以我国传统大豆发酵食品和稻草样品为来源,根据蛋白酶和纳豆激酶活性、产聚谷氨酸(poly-L-glutamic acid,γ-PGA)性能和生物素依赖特性进行筛选,分离获得了8株具有纳豆芽孢杆菌特性的枯草芽孢杆菌菌株。利用16S~23S rRNA内转录间隔区(internal transcribed spacer,ITS)序列对分离菌株进行系统发育分析,结果显示其与已报道的纳豆芽孢杆菌菌株以较高的相似性(93%~97%)聚类一簇,独立于同种内的其他枯草芽孢杆菌。其中TC100和TC103菌株制作的纳豆粗酶液中的纳豆激酶活性最高,分别为550 U/mL和519 U/mL。HN48和TC100菌株发酵纳豆的感官效果最好,评价分数均为19分。综上所述,本研究根据纳豆芽孢杆菌特有的性状,有效分离获得了具有纳豆芽孢杆菌特性的8株菌株,通过菌株形态和ITS基因序列的系统发育分析确定分离菌株均属纳豆芽孢杆菌,8株分离菌株均能产纳豆激酶,发酵生产纳豆的感官效果良好,有望作为纳豆生产的工业菌株。 相似文献
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分离鉴定溶栓酶高产菌株,对其所产溶栓酶的类型、相对分子质量及发酵曲线进行特性分析。从中国豆豉中分离一株纤溶酶高产菌株MX-6,经个体形态、菌落形态及16S r DNA基因同源性比对,确定该菌株为枯草芽孢杆菌。应用聚合酶链式反应(polymerase chain reaction,PCR)克隆到1 473 bp的纤溶酶编码基因apr N,根据推测氨基酸序列与同源序列的多序列比对及系统进化树结果显示该纤溶酶为纳豆激酶。SDS-聚丙烯酰胺凝胶电泳法(SDS-polyacrylamide gels electrophoresis,SDS-PAGE)确定枯草芽孢杆菌MX-6所产纳豆激酶的相对分子质量约28 ku,与预测的相对分子质量27 712. 72 u相吻合。枯草芽孢杆菌MX-6所产纳豆激酶的发酵曲线结果显示在72 h达到纳豆激酶最大合成量,在纤维蛋白平板上的溶圈直径高达21. 60 mm。为更好地实现纳豆激酶的开发及应用提供一定的理论依据和方法参考。 相似文献
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以产3-羟基丁酮枯草芽孢杆菌(Bacillus subtilis)TH-49(Val-)和产α-乙酰乳酸脱羧酶地衣芽孢杆菌(Bacillus licheniformis)AD-30为亲本菌株,以聚乙二醇为融合促进剂,进行原生质体融合获得融合子,融合子经再生、筛选等过程,最终获得高产3-羟基丁酮菌株HB-32,该菌株3-羟基丁酮产量高达49.64 g/L,比菌株TH-49(Val-)提高了61.8%,且遗传稳定性良好。进一步采用随机扩增多态性DNA(RAPD)技术,从分子水平上分析了高产3-羟基丁酮菌株HB-32与亲本菌株基因组的变化。结果表明,枯草芽孢杆菌(B. subtilis)TH-49(Val-)和地衣芽孢杆菌(B. licheniformis)AD-30原生质体融合成功,提高了融合子HB-32 3-羟基丁酮产量。 相似文献
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以枯草芽孢杆菌BJ3-2的glsA1基因为同源序列,通过构建单交换整合载体,将高活性谷氨酰胺酶基因glsA2定点整合入BJ3-2菌株染色体中,获得能够稳定遗传的重组菌株BJ3-2A2。经检测重组菌株谷氨酰胺酶活力为BJ3-2菌株的3.36倍。利用重组菌株BJ3-2A2发酵豆豉,全氨基酸检测显示,重组菌株发酵的豆豉谷氨酸含量比出发菌株高12.8%。说明枯草芽孢杆菌BJ3-2可以转化且为RecE+菌株,glsA2基因在BJ3-2菌株染色体上可实现较高活性表达,并提高发酵豆豉的鲜味。 相似文献
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以枯草芽孢杆菌BJ3-2 的glsA1 基因为同源序列,通过构建单交换整合载体,将高活性谷氨酰胺酶基因glsA2 定点整合入BJ3-2 菌株染色体中,获得能够稳定遗传的重组菌株BJ3-2A2。经检测重组菌株谷氨酰胺酶活力为BJ3-2 菌株的3.36 倍。利用重组菌株BJ3-2A2 发酵豆豉,全氨基酸检测显示,重组菌株发酵的豆豉谷氨酸含量比出发菌株高12.8%。说明枯草芽孢杆菌BJ3-2 可以转化且为RecE+ 菌株,glsA2 基因在BJ3-2 菌株染色体上可实现较高活性表达,并提高发酵豆豉的鲜味。 相似文献
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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
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John Gilbert Catherine Simoneau David Cote Achim Boenke 《Food Additives & Contaminants》2000,17(10):889-893
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
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
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
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
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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M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
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
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《肉类研究》2014,(2)
<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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《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
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《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