耐高酒精野生酵母菌株的筛选及其特性研究

以从内蒙古各旗县果园的果实和土壤中分离得到的200株酵母菌为出发菌株,经四级筛选最终得到一株酒精耐受力为16%vol的菌株K1-2,并对该菌株的发酵特性与生物学特性进行了研究。结果表明,该酵母菌的最适生长pH值为5.5,最适生长温度为28 ℃,最高可耐受600 mg/L的SO2,在葡萄糖含量为60%的条件下仍可生长。发酵5 d后糖醇转化率可达68.45%,产酒精度为6.4%vol,表明该菌株是一株具有良好酒精耐受性与发酵性能的酵母菌株,除拥有较高的耐SO2与耐高糖能力以外,还具备较强的产酒精能力,有很高的应用价值。     

一株果醋发酵氧化葡糖杆菌的鉴定及发酵特性

从自然发酵果醋中分离和筛选到一株产醋酸的菌株E3,通过形态培养特征、生理生化特征、16S rDNA序列比对及系统发育分析,鉴定菌株E3是氧化葡糖杆菌(Gluconobacter oxydans).菌株E3最适生长和产酸温度为30℃,在20℃～30℃内,菌株生长和产酸性能较稳定.菌株E3最适生长pH值为6,耐酸性较好,pH值为为3时菌体仍能生长.E3能耐受6％vol的乙醇浓度而不影响产酸能力,6％vol乙醇浓度发酵6d酸度达到4.12g/100mL.菌株E3产酸和耐酸性能好,能耐受6％乙醇浓度产酸,为果醋发酵提供了新的菌种资源.     

窖泥中高产丁酸梭菌的筛选、鉴定及其生长耐受性研究

从浓香型白酒窖泥中通过传统微生物分离手段筛选高产丁酸的梭菌,并对分离菌株进行形态学观察、分子生物学鉴定及生长耐受性分析研究。结果表明,通过发酵产物检测获得两株高产丁酸菌株,编号为AB2RH027和AB2RH033,经过菌落观察、革兰氏染色及分子生物学鉴定两株菌均为丁酸梭菌（Clostridium butyricum）。通过耐受性实验,确定菌株AB2RH027最适生长pH值为8,最适生长温度为40 ℃,酒精耐受性为15%vol,发酵24 h丁酸产量为5.29 g/L;菌株AB2RH033最适生长pH值为8,最适生长温度为35 ℃,酒精耐受性为18%vol,发酵24 h丁酸产量为5.23 g/L。该研究筛选得到的两株高产丁酸的菌株在白酒品质提升方面具有一定应用价值。     

发酵木糖酵母菌株的选育

本文介绍了发酵木糖产酒精酵母菌种的筛选方法并利用该方法筛选出一株性能优良的发酵木糖产酒精酵母菌株Zs。该菌株性能测试结果为：发酵木糖产乙醇能力相当于理论产量的60．0％；发酵葡萄糖浓度为8％的发酵液，乙醇转化率为0.388g/g；最低乙醇抑制浓度14％（v/v)；在温度高达42℃的条件下仍能正常生长。并初步鉴定该菌株为奥默毕赤氏酵母（Pichia ahmeri)。     

丁酸梭菌的分离、鉴定与基本特性研究

通过厌氧培养法从朗姆酒发酵过程添加的丹多液中分离得到9株纯菌株,经过生理生化实验和16S r DNA序列分析鉴定出1株丁酸梭菌Y-1。研究了Y-1的基本生长特性和安全性,结果表明,其具有较强的耐酸和耐酒精以及产酸能力,发现菌株在梭菌增殖培养液中最适生长温度为37℃,最适生长p H值为7.0,菌株对于酒精的最高耐受能力为9%vol,耐酸能力最低p H值为4.0。丁酸梭菌作为功能微生物在朗姆酒发酵过程中对香气及风味物质的形成具有重要作用。     

一株耐高浓度乙醇酒精酵母的筛选及发酵特性的研究

为获得乙醇耐受性较高的酵母菌,通过富集培养,从白酒窖池的酒糟中分离筛选出一株耐18%vol乙醇浓度的菌株A2。其最适生长温度为32℃,最适pH值为4.5。通过正交试验得出A2的最优发酵条件为葡萄糖浓度20%(w/v),温度34℃,pH值为4.5。发酵72h后,发酵液酒精浓度达到9.5%vol。     

适合鸭梨果酒酿造酵母菌Y-5的基本生理特性研究

本试验从梨果园土壤中分离出一株产香性能好的酵母菌株Y-5，经鉴定为酵母属（Saccharomyces）的酿酒酵（Sacchromuces cerevisiae）。研究结果表明，Y-5菌株的最适生长温度为36℃，最适生长pH值为4．5；最适发酵温度为30℃，最适发酵pH值为4．5；温度和接种量对生长和发酵曲线的影响显著，pH值对生长和发酵曲线的影响不显著。     

一株耐酒精酵母菌的选育研究

从来源不同的基质中分离得到100株酵母菌,经初筛、复筛和酒精发酵试验,最终获得一株耐酒精度为16%vol酵母菌株,编号为TA-24。研究了温度和pH对生长和发酵的影响。结果表明,其最适生长温度为30℃,最适生长pH为4.5;最适发酵温度为30℃,最适发酵pH为4.5。     

高产酒精絮凝酵母SY-130菌株的选育

以絮凝性强的葡萄汁酵母SN-154和高产酒精酵母菌种NHY4-36做亲本，通过原生质体融合技术，获得一支发酵速度快、高产酒精且絮凝性强的酵母菌株SY-130，以玉米淀粉为原料，32℃发酵60—68h，可产酒精17．5—18．5％(v／v)，耐酒精度可达20％以上，酵母絮凝性能良好。     

耐高温酵母的筛选鉴定及发酵性能的初步研究

为获得耐高温酵母菌,从白酒糟醅中分离筛选出1株在45℃生长良好且产乙醇能力较高的酵母菌株.经ITS和26S rDNAD1/D2区域序列分析比对,结合菌落菌体形态鉴定其为库德毕赤酵母.其最适生长温度为30℃,与安琪酵母相比较,高温条件下生长优势明显.以浓度为10％ (w/v)的葡萄糖为底物,在45℃进行静置发酵,其产乙醇浓度为18.74g/L,安琪酵母产乙醇浓度为11.40g/L,该菌株较安琪酵母表现出明显的优势.     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

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.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

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.     

European priorities for research to support legislation in the area of food contact materials and articles

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<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