100m3发酵罐上面发酵小麦啤酒生产工艺技术研究

详细介绍了100立方米发酵罐上面发酵小麦啤酒生产工艺技术及质量控制标准.     

进境加拿大大麦中真菌病害的分离与鉴定

目的分离与鉴定进境加拿大大麦中真菌病害。方法从进境加拿大大麦的可疑种子及病残体中分离获得真菌菌株,并对所分离的菌株进行培养性状及形态学观察,同时对核糖体DNA内转录间隔区(internal transcribed spacer,ITS)扩增和测序,进行鉴定。结果共分离出21个真菌菌株,鉴定出6个菌种,包括黑麦麦角菌(Claviceps purpurea)、梨孢镰刀菌(Fusarium poae)、燕麦镰刀菌(Fusarium avenaceum)、细极链格孢(Alternaria tenuissima)、大麦网纹病菌(Pyrenophora teres)、颖枯壳针孢(Phaeosphaeria nodorum)。结论做好进境大麦的检疫、监管工作,对保障啤酒工业安全生产、防止外来危险性病原菌在我国定殖、流行以致造成危害具有极其重要的意义。     

顶空进样-毛细管柱气相色谱法检测果啤风味物质

利用顶空进样、小口径毛细管柱气相色谱法测定果啤风味物质的含量。该方法采用氢火焰离子化检测器，并用面积归一化法进行计算。实验结果表明，分离色度高，色谱峰对称，平均回收率在98％以上，相对标准偏差在1％之内；该方法重现性好、简单、方便、快速、准确，能满足对分析检测的需要。     

ESTIMATION OF ALPHA AMINO NITROGEN

The free alpha amino nitrogen in wort and beer has been estimated by reaction with trinitrobenzene sulphonic acid (TNBS) either at 40°C for 2 h or at 60°C for 30 min. Statistical analysis shows that for worts there is no significant difference between results obtained under the two sets of conditions, but for beers the values are higher when determined at 60°C by amounts which vary from beer to beer. However, there is no loss in precision (± 2 SD) so that the more rapid method can be used with advantage.     

A SIMPLE METHOD FOR THE ISOLATION OF PURINE NUCLEOSIDES FROM WORT AND BEER USING COLUMN CHROMATOGRAPHY

Column chromatography using a variety of dextran based gel matrices was used to fractionate nucleosides in wort and beer. The gel matrices Sephadex G10 and Sephasorb HP Ultrafine were found to elute guanosine, deoxyguanosine, adenosine and deoxyadenosine in a single fraction whereas Sephadex LH20 and Sephadex G25 both yielded two fractions containing nucleosides. The first nucleoside containing fraction from Sephadex LH20 contained guanosine and the second fraction contained deoxyguanosine, adenosine and deoxyadenosine. In contract the first nucleoside containing fraction from Sephadex G25 contained both adenosine and deoxyadenosine and the second fraction contained guanosine and deoxyguanosine. Fractionation of low molecular weight components from wort and beer by column chromatography provides a simple technique for the isolation of purine nucleosides. This may be used to monitor directly the presence of purine nucleosides throughout the brewing process and to obtain quantitative estimates of the content of purine nucleosides in beer.     

YEAST EXTRACELLULAR PROTEOLYTIC ENZYMES FOR CHILL-PROOFING BEER

Yeast belonging to various genera were screened for extracellular protease activity. Of the 119 strains examined the most prolific protease producers belonged to the genera Candida, Kluyveromyces and Hansenula. No strains of Sacharomyces were found to secrete protease. In general only those proteases secreted by the genus Candida possessed chill-proofing activity. However one strain of Debaryomyces and one of Pichia also produced proteases with chill-proofing activity.     

THE CONTENT OF SOME ORGANIC ACIDS IN BEER AND OTHER FERMENTED MEDIA

The acid content of a range of ales and lagers has been measured for some organic acids related to the Krebs cycle, and found to vary widely. Acetate, pyruvate, lactate, succinate, pyroglutamate, malate and citrate were present in all cases and α-ketoglutarate was usually detected. α-Hydroxyglutarate was recognized in a number of beers. The effect of the acids on the pH of beer is assessed. The strain of yeast which is used markedly influences the levels of all acids except pyroglutamate and the conditions of yeast propagation have a substantial influence on the extent of acid accumulation. During the fermentation of wort and synthetic media the extent of organic acid excretion is proportional to the extent of fermentation, but the nature of the acids which are excreted varies during the fermentation period. In synthetic media, nitrogen source is shown to have a substantial effect on the accumulation of organic acid. Pyruvate and acetate levels vary inversely towards the end of fermentation, suggesting that yeast converts pyruvate to acetate.     

利用啤酒酵母生产SOD的提取条件研究

研究了利用异丙醇破壁、丙酮二次纯化提取SOD生产工艺,最佳提取条件为:异丙醇浓度为90%、时间120min、pH7.0,粗酶液的收率为73%,所得SOD的酶比活为3048.7u/mg.与胞内SOD提取老工艺相比,具有工艺简单、设备少、操作简便、成本低等特点.(孙悟)     

仙人掌啤酒的开发研制

在啤酒生产过程中,适量加入仙人掌汁,研制生产出具有一定疗效保健作用的仙人掌啤酒。该产品具有清热解毒、提高肌体的免疫力等功能,适量饮用,可预防感冒、强身健体,尤其适于夏季饮用。     

一个评价啤酒老化程度的新指标--DPPH清除率

啤酒具有一定的内源性抗氧化能力可以清除自由基.利用分光法测定啤酒对DPPH自由基的清除率,来表示啤酒的抗氧化能力,以评价其老化程度,结果显示清除率与老化程度之间有相当高的线性相关性.与TBA法对应,分别考察同一品牌经强制老化啤酒、经自然贮存的啤酒、不同生产批次的啤酒和不同品牌啤酒,该法显示出极强的优越性,尤其是用于评价不同品牌啤酒的老化程度.