共查询到20条相似文献,搜索用时 234 毫秒
1.
为获得高产富硒酵母,通过硒浓度梯度驯化啤酒酵母Sac.cerevisiae Fec205、戴氏酵母Sac.delbrueckii Fec209、热带假丝酵母Candida tropicalis Fec2011等3株酵母菌,结果显示啤酒酵母Sac.cerevisiae Fec205比其他2株酵母的耐硒性能更强。因此以啤酒酵母Sac.cerevisiae Fec205为原始菌株进行紫外诱变以提高其富硒能力。通过硒抗性筛选,挑取出6株生长快、菌落大的突变菌株单菌落。取发酵培养基中生物量大的3株酵母菌Sac.cerevisiae Y-3,Y-4,Y-1,接种于硒浓度为40μg/ml发酵培养基,结果显示选育出的3株诱变后的啤酒酵母Sac.cerevisiae Y-3,Y-4,Y-1的硒含量分别为932、832、915μg/g,其中最高的Y-3比原始菌株啤酒酵母Sac.cerevisiae Fec205的硒含量增长50.08%、生物量提高了50.97%。 相似文献
2.
现代啤酒酵母菌种改良途径 总被引:1,自引:0,他引:1
当前啤酒酵母的改良途径有:诱变选育、杂交育种、原生质体融合,以及通过基因工程可培育出许多性能优良的啤酒酵母菌株。本文对上述各种育种方式在酿酒酵母菌种选育方面的应用作一个较为全面的综述,希望能够对啤酒行业,尤其是从事菌种选育方面研究人员有所帮助。 相似文献
3.
五酵母菌种的选育及酵母处理在菌种选育方面已成功的工作是: 1.将许旺酵母的α—淀粉酶和糖化酶基因成功地克隆在啤酒酵母中,从而使直接利用淀粉无需经过糖化就可进行发酵酿造成为可能,并可用于生产低热量啤酒。 2.英国的Bass和Whitbread公司已成功地将β—葡聚糖酶基因克隆在啤酒酵母中。应用此菌株酿酒可解决β—葡聚糖引起的混浊,并可降低啤酒粘度,加速过滤。 相似文献
4.
以实验室保藏的2株耐糖酵母为出发菌株,采用紫外诱变法对这2株酵母进行诱变处理,选育出耐高糖且具有高发酵度的酵母菌株并进行特性研究。结果表明:紫外诱变条件为30 W紫外灯,照射距离50 cm,对于酵母CX1菌株照射时间为(60~150)s,而CXJ-1菌株照射时间为(120~150)s;诱变后菌株的耐糖特性和产酒精特性均有提高,菌株CX13对糖、SO_2、pH及酒精的最大耐受浓度分别为65%、500 mg/L、1.5、14%vol。且菌株发酵度比工业菌株提高6%,酒精度提高1.4%vol,具有很好的研究价值和应用前景。 相似文献
5.
6.
7.
8.
耐低温耐酒精白葡萄酒酵母的选育 总被引:4,自引:0,他引:4
本文通过对白葡萄酒酵母R2进行紫外线诱变的方法进行定向选育和驯化,筛选出耐低温菌株,再与耐酒精酵母进行有性杂交,筛选出在保持原有发酵性能的条件下具备耐低温耐酒精的特性的菌株。 相似文献
9.
10.
高产胡萝卜素红酵母突变株的选育 总被引:2,自引:0,他引:2
以红酵母为初发菌株,经等离子体诱变处理,选育出高产胡萝卜素的红酵母突变株,初步确定了促使胡萝卜素质量提高的适宜培养基组成及培养条件,经96h发酵后,菌体胡萝卜素含量达5.10ug/ml比出发菌株提高59.4%。 相似文献
11.
以青岛啤酒酵母和高浓精酵母为供试菌株,筛选出生长良好的酵母,为选育具有青岛啤酒风味的高浓酵母做准备.比较了7株酵母不同糖类发酵、离子抗性、二氧化碳减重、发酵液风味品评等指标.结果表明:T1、T2和T3是传统的青岛啤酒发酵菌株,其发酵液口味符合青岛啤酒口味要求,且对Cu2+均不耐受;而G4和G6发酵减重试验和风味物质分析中的乙醛含量指标的评价均优于G5和G7菌株,且它们的发酵液的风味也接近青啤口味.因此,选择T1、T2、T3和G4、G6作100L酿造试验,进一步确定融合亲株. 相似文献
12.
《Food microbiology》2000,17(2):217-223
This work compared the efficiency of four methods for the identification of industrial yeast strains and the establishment of a pattern for yeast characterization to be used during industrial fermentation processes, allowing the detection of yeast contaminants. Five strains of yeast currently used in the Brazilian fuel alcohol industry (about 99% of the yeast used for this purpose), and yeast strains isolated from the five major beer industries that represent 95% of the Brazilian beer market were evaluated for their growth and absorption of dyes on differential culture media, their total protein electrophoretic patterns (SDS–PAGE), CHEF chromosome separation patterns, and RAPD profiles. For the identification of brewing yeast, all tested methods were efficient, allowing the identification of at least two different species, one of which wasSaccharomyces cerevisiae . The strains used for the fuel alcohol industries were best characterized by SDS–PAGE and RAPD analysis. Those strains share high level of genetic similarity and they are all known as S. cerevisiae strains. 相似文献
13.
Screening for new brewing yeasts in the non‐Saccharomyces sector with Torulaspora delbrueckii as model
下载免费PDF全文
![点击此处可从《Yeast (Chichester, England)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Maximilian Michel Jana Kopecká Tim Meier‐Dörnberg Martin Zarnkow Fritz Jacob Mathias Hutzler 《Yeast (Chichester, England)》2016,33(4):129-144
This study describes a screening system for future brewing yeasts focusing on non‐Saccharomyces yeasts. The aim was to find new yeast strains that can ferment beer wort into a respectable beer. Ten Torulaspora delbrueckii strains were put through the screening system, which included sugar utilization tests, hop resistance tests, ethanol resistance tests, polymerase chain reaction fingerprinting, propagation tests, amino acid catabolism and anabolism, phenolic off‐flavour tests and trial fermentations. Trial fermentations were analysed for extract reduction, pH drop, yeast concentration in bulk fluid and fermentation by‐products. All investigated strains were able to partly ferment wort sugars and showed high tolerance to hop compounds and ethanol. One of the investigated yeast strains fermented all the wort sugars and produced a respectable fruity flavour and a beer of average ethanol content with a high volatile flavour compound concentration. Two other strains could possibly be used for pre‐fermentation as a bio‐flavouring agent for beers that have been post‐fermented by Saccharomyces strains as a consequence of their low sugar utilization but good flavour‐forming properties. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
14.
G. G. Stewart C. R. Murray C. J. Panchal I. Russell A. M. Sills 《Food microbiology》1984,1(4):289-302
In order to achieve a beer of high quality, the yeast culture must be effective in removing the desired nutrients from the growth medium (i.e. the wort), it must impart the required flavour to the beer and finally, the micro-organisms themselves must be effectively removed from the fermented wort after they have fulfilled their metabolic role. Brewer's wort contains the sugars sucrose, fructose, glucose, maltose and maltotriose, together with dextrin material. In the normal situation, brewer's yeast strains are incapable of fermenting the dextrin material; however, yeast strains capable of fermenting at least a part of this dextrin material and producing a palatable beer are now available.One of the important factors known to affect the fermentation rate is the intracellular yeast glycogen concentration which has been found to be influenced by storage conditions. The glycogen level at pitching significantly affects the fermentation rate of the yeast culture. 相似文献
15.
Leonardo Petruzzi Maria Rosaria Corbo Milena Sinigaglia 《Food Reviews International》2016,32(4):341-363
Historically, brewing beer came from uncontrolled spontaneous fermentations; nowadays, spontaneous fermentation is still used in speciality products such as Belgian acid beers (e.g., lambic, gueze, and Rodenbach) or in various traditional beers worldwide. On the other hand, industrial fermentations sometimes require a combination of phenotypic traits that might not be commonly encountered in nature. In some cases, the demand for increased productivity, as well as changing consumer preferences, leads to a great interest towards improvement and/or design new strains or yeast variants. This review addresses the following topics: controlled and uncontrolled fermentations, and advances in the selection of novel, nonconventional, and superior strains for beer. 相似文献
16.
Michael Lentz Travis Putzke Rick Hessler Eric Luman 《Journal of the Institute of Brewing》2014,120(4):559-564
‘Wild’ and spontaneously fermented beers are growing in popularity in the craft beer industry. Most of these beers are fermented by the use of either pure cultures of unconventional yeast and bacteria or spontaneous fermentation using mixed local microflora. This study examined the potential of using pure strains of new isolates of wild yeast in the fermentation of a unique beer. The microbial communities from the fruit of pindo palm, loquat, hackberry and blackberry were collected in liquid culture, then plated for isolation. Ten isolates were selected for further analysis. Strains were identified by restriction fragment length polymorphism (RFLP) analysis and analysed for growth in a simple liquid media, fermentation in a complex media, alcohol tolerance and acid tolerance. Despite identification of some strains as the same species, they displayed a wide range of physiological properties. All strains were tolerant of pH values as low as 2.4, but none were tolerant of pH 1.9. Alcohol tolerance of different strains varied from 6 to 12%. Several strains had properties that suggest potential as primary fermenters, including the alcohol fermentation of a beer wort. Organoleptic properties of beers fermented with several of the strains demonstrated potential for commercial brewing. Copyright © 2014 The Institute of Brewing & Distilling 相似文献
17.
Total soluble cell proteins from 33 yeast strains from the brewing industry were extracted and subjected to polyacrylamide gel electrophoresis. Yeast strains were grouped by computerized numerical analysis of protein banding patterns. Three clusters were obtained at r>0.90. Cluster I contained 21 Saccharomyces cerevisiae lager beer strains. Cluster II comprised two strains isolated from beer with a phenolic off flavour and a third strain used for lager beer brewing. Cluster III consisted of two bottom ale yeasts. Protein patterns of yeast strains within each cluster corresponded closely or were identical. However, the intensity of certain bands often varied and the number of peaks recorded was not identical. These minor differences were reproducible and regarded as characteristic for the specific strains. Protein patterns can therefore be used to characterize or fingerprint individual yeast strains. 相似文献
18.
啤酒酵母的基因改良研究动态 总被引:7,自引:0,他引:7
近年来 ,利用基因工程进行酵母的育种在发酵广谱碳水化合物、提高糖化效率 ,改良酵母凝聚特性和改善啤酒风味方面取得了很大成绩。基因重组菌株将逐步应用到生产实践中。 相似文献
19.
“SP-3”是新选育的啤酒酵母菌株,而“SP-2”为通常生产大麦芽啤酒使用的啤酒酵母菌株,“SP-3”与“SP-2”啤酒酵母菌株在全小麦啤酒生产中应用对比试验结果表明,“SP-3”啤酒酵母菌株在全小麦芽啤酒的酿造中适用性较强,各项指标均优于“SP-2”啤酒酵母菌株,用其酿制的啤酒口感纯正、清爽、柔和,能够较好地适应当前消费者的口感需求. 相似文献
20.
Koji Suzuki Kazumaru Iijima Shizuka Asano Hidetoshi Kuriyama Yasushi Kitagawa 《Journal of the Institute of Brewing》2006,112(4):295-301
Strong beer spoilage strains Lactobacillus lindneri DSM 20692 and Lactobacillus paracollinoides JCM 11969T were repeatedly subcultured in degassed beer and their culturability on MRS agar was examined. As a result, the two strains were found to show decreased culturability, suggesting that the prolonged contact with beer reduces the culturability of beer spoilage lactic acid bacteria (LAB). After 30 subcultures in degassed beer, both strains were subjected to sublethal heat treatment. As a consequence, L. lindneri DSM 20692 and L. paracollinoides JCM 11969T were no longer detectable on MRS agar despite the presence of 460 viable cells, indicating that the viable but nonculturable (VNC) states were induced for both strains. Problematically, the heat treated VNC strains were shown to exhibit beer spoilage ability, suggesting that spoilage incidents can occur without detection by culture media. It was also shown that, once acquired, the VNC states are stably maintained in beer without further heat treatment. These results suggest the possibility that beer spoilage LAB strains remain hidden in pitching yeast and work‐in‐process products without detection. Furthermore L. lindneri DSM 20692 and L. paracollinoides JCM 11969T in VNC states were successfully stored at ?80°C with 10% dimethyl‐sulfoxide as a cryoprotectant and reconstituted in degassed beer without losing VNC characteristics. Taken together, these findings show that valuable bioresources can be acquired from culturable beer spoilage LAB strains and maintained for long‐term storage as frozen culture stocks. 相似文献