肠膜明串珠菌肠膜亚种Z_25在苹果酒中发酵特性的研究

从发酵温度、接种量、酒精度、起始苹果酸浓度等方面研究了肠膜明串珠菌肠膜亚种Z25的苹果酸乳酸发酵（MLF）能力,确定了肠膜明串珠菌MLF适宜条件为温度20℃、接种量6%、酒精度10%（v/v）以及起始苹果酸浓度4.0g/L。按此工艺酿制,发酵时间12d后苹果酒中的乳酸含量由0.99g/L提高到了3.5g/L,苹果酸含量从4g/L下降到0.25g/L,且苹果酸降解发生在菌株Z25的对数生长阶段。显然,辅助肠膜明串珠菌肠膜亚种Z25到苹果酸乳酸发酵中,可以改善苹果酒的品质。     

肠膜明串珠菌在苹果酒苹果酸乳酸发酵中的应用探讨

通过在苹果酒中添加肠膜明串珠菌启动苹果酸乳酸发酵,研究了温度、pH和酒精度等因子对苹果酸-乳酸发酵的影响表明,肠膜明串珠菌能够启动苹果酸-乳酸发酵,其中温度、pH和酒精度均对苹果酒的柔和指数和感官评价有显著影响,不同发酵条件下酿造的苹果酒柔和指数在1.33～7.94之间,感官评分在73.7～91.3之间.添加肠膜明串珠菌后,苹果酸的浓度变化在322.45mg/L～692.44mg/L之间,pH值提高了约0.06～0.11,苹果酒的口感变得柔和,风味得到明显改善.     

苹果酒酿造中的苹果酸-乳酸发酵

在苹果酒酿造中进行苹果酸-乳酸发酵,乳酸菌通过分解苹果酸,产生乳酸,引起其他有机酸的变化,使苹果酒的口感、质量得以改善。pH、温度、SO_2、酒度通过影响乳酸菌的活动而影响苹果酸-乳酸发酵的进行。保证苹果酒苹果酸-乳酸发酵进行的条件为:温度16～18℃,总SO_2含量<70mg/L,pH<3.70,酒精体积分数低于13％。     

苹果酸乳酸发酵的研究进展

苹果酸乳酸发酵是现代葡萄酒、苹果酒酿造工艺中非常重要的二次发酵过程。葡萄酒、苹果酒经过苹果酸乳酸发酵以后 ,原有的酸涩和粗糙感降低 ,而变得柔和、圆润且具有果香味。文中根据国内外研究成果 ,分析总结了苹果酸乳酸发酵的机理并且对苹果酒酿造过程中乳酸菌的一些生长特性进行了阐述。在此基础上 ,论述了现代生物技术在苹果酒和葡萄酒生产中的新应用。     

甜苹果酒的发酵工艺优化

发酵工艺对苹果酒品质有重要影响.以感官质量为评价指标,以发酵温度、糖度、酸度、接种量为试验因素,进行四因素三水平正交试验,对甜苹果酒主发酵工艺进行优化.甜苹果酒主发酵的最佳工艺条件是:发酵醪调至糖度20°Bx、酸度(按苹果酸计)6g/L,按接种量为0.25g/L接入酵母,在18℃温度下发酵7d,前1～2d对发酵醪进行通...     

添加肠膜明串珠菌后的苹果酒苹果酸乳酸发酵工艺优化研究

以苹果酒风味的柔和指数为指标,对添加肠膜明串珠菌后的苹果酒苹果酸乳酸发酵(MLF)工艺条件进行优化。结果表明,发酵温度、pH和肠膜明串珠菌接种量等因素会影响MLF后的苹果酒柔和指数;采用二次正交回归旋转实验确定了苹果酒MLF的适宜工艺参数为:发酵温度21.78℃,pH 3.53,肠膜明串珠菌接种量4.65%(v/v),按该工艺生产柔和指数从2.73提高到3.54,苹果酒的风味得到了明显改善。     

苹果酒苹果酸乳酸发酵乳酸菌的筛选

首先根据乳酸菌对苹果酒风味的贡献情况筛选出 3株乳酸菌 ,再从微生物角度对乳酸菌的生理特征以及环境因素对乳酸菌生长的影响进行了研究和比较 ,发现OenococcusoeniL4能够在SO2 和乙醇体积分数分别为 5 0mg/L和 6% ,pH 3 .2时良好的生长 ;该菌具有良好的苹果酸降解能力 ,达到 2 2 8 5 2mg/(L·d) ,表明O oeniL4能够适应于我国起泡苹果酒的酿造 ,是 1株优良的苹果酒苹果酸乳酸发酵菌株。     

苹果酸-乳酸发酵对军果酒风味的影响

介绍了苹果酸 -乳酸发酵 (简称MLF)的机理、苹果酒发酵过程中苹果酸 -乳酸发酵的控制及苹果酸-乳酸发酵对苹果酒风味的影响     

山葡萄酒苹果酸—乳酸发酵工艺优化

为改善山葡萄酒的风味,对其苹果酸—乳酸发酵工艺条件进行优化。结果表明,山葡萄酒苹果酸—乳酸发酵的最佳工艺条件:初始pH 3.00,温度20℃,接种量4mL/100mL,含糖量10.7g/L。在最佳工艺条件下对东北山葡萄酒进行二次发酵,制品pH值相对于原发酵葡萄汁升高0.19±0.05,总酸度(以苹果酸计)相对于原发酵葡萄汁降低(2.67±0.10)g/L,缓解了山葡萄原酒的酸涩味,增加了适口性。     

荔枝酒生产工艺研究

以"黑叶"荔枝原汁为原料,研究了不同活性干酵母菌种、不同发酵工艺对荔枝酒发酵的影响,研究了荔枝酒的澄清工艺,分析了荔枝酒发酵前后的糖酸变化.结果显示,荔枝酒的较优发酵菌种为DV10,较适发酵温度为20℃,添加偏重亚硫酸钾对防止褐变无效果,采用50mg/L壳聚糖可获得较好的澄清效果.发酵后残余的糖为果糖,含量小于4 g/L,发酵结束后苹果酸有所下降而乳酸有所增加,发酵过程可能存在苹果酸乳酸发酵.     

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.     

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     

Chinese CTP Market

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%.     

Preparatory Work of Print China 2015 is Going Smoothly

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