PCR技术快速检测鉴定啤酒中的污染菌和破坏性菌

现代啤酒由单一菌种——酵母发酵而成。但在整个啤酒酿造过程中,酿造设备、空气、酿造用水等诸多因素都有可能导致有害微生物进入麦汁或发酵液中,如果这些有害微生物大量生长繁殖,就会污染麦汁或啤酒。污染腐败的细菌对啤酒的质量影响相当大,     

啤酒酿造过程中的微生物控制要点分析

正啤酒被人们称之为"液体面包",与我们的生活息息相关。在啤酒生产过程中,为了保证啤酒的质量和生物稳定性,应该控制好啤酒中的微生物。只有做好微生物控制的各个细节,才能保证啤酒的口感和质量,下面就啤酒生产过程中的微生物控制途径进行分析。啤酒酿造过程中的有害微生物在啤酒酿造过程中,细菌和霉菌是最重要的有害微生物。细菌有有益菌和有害菌之分,而目前所说的是有害菌,它主要包括了乳酸杆菌、四联     

啤酒生产过程中有害微生物的监测与检验

在啤酒酿造过程中，常会有数量不等的有害微生物侵入，造成啤酒的混浊、酸败或回味异常。为生产高质量、口味纯正的啤酒，必须注意生产过程中有害微生物的监测，建立起一套系统、完整的监测检验手段。1．啤酒生产过程中存在的有害微生物种类及主要特性啤酒生产过程中有害微生物     

发酵液厌氧菌的控制

目前国内一些中小啤酒厂微生物污染（尤其是微好氧微生物）还比较严重，对啤酒风味影响较大，本文着重阐述了微生物的危害，啤酒有害菌污染的途径，以及如何防止与控制酿造过程中的微生物污染。     

啤酒酿造中的微生物污染

由于啤酒酿造的环境奈件,如营养丰富的麦芽汁、发酵过程中酵母产生的生长因子以及较长的发酵时间等非常适宜于微生物的生长,所以在啤酒酿造中许多环节都存在微生物污染的可能性。啤酒酿造过程中的微生物污染不仅会影响产品的质量,严重时还会给啤酒生产厂家造成一定的经济损失。介绍了啤酒酿造过程中的污染微生物的种类、来源以及对啤酒质量的影响。通过了解啤酒酿造中微生物的污染情况,可以有助于我们生产高质量的啤酒产品.     

精酿啤酒杀菌前后的微生物鉴定

尽管酿造啤酒是相对安全的生产过程,难免仍存在有害微生物的生长。避免微生物污染最有效的方法是进行适当的杀菌和保持良好的卫生环境以控制污染。本实验的目的是在酒吧精酿啤酒生产过程中进行一定特殊的卫生处理,并鉴定卫生处理前后的微生物菌群。各种选择性分离培养基用于啤酒有害菌的计数是很有效的,但与现代技术相比,这些方法显得比较耗时。而利用精确的分子方法,加上常规的微生物分析可以快速的鉴定啤酒中的微生物。这一结果表明良好的卫生环境对防止有害微生物的污染非常重要。CIP系统清洗可以用来避免微生物的污染。     

啤酒污染菌快速检测和鉴定方法的研究

[概述]啤酒酿造过程中重要的微生物有酵母、细菌、霉菌类。啤酒中含有酒精及来源于酒花的苦味成分,pH 值比较低,对于细菌特别是革兰氏阳性菌具有抑制作用。另外,经煮沸杀菌的麦汁是在低温下进行厌氧发酵,所以相对限制了在啤酒中可能繁殖的微生物种类。但啤酒中存在着有害菌,所谓有害菌就是指损害啤酒产品质量的菌。在啤酒中,当酿造用酵母以外的微生物繁殖时,与酵母的代谢物质相比,分泌出一些不同的物质,当分泌代谢物的量超过感官阈值时,就会损害啤酒的质量。啤酒生产中常见的污染菌包括:     

浅谈纯生啤酒生产中微生物控制

纯生啤酒采用无菌酿造、无菌过滤、无菌包装,生产纯生啤酒的关键是防止和控制有害微生物的污染,即从生产的各个环节入手对微生物进行严格管理和控制,以保证啤酒的微生物安全,它包括纯种酿造、无菌过滤、无茵罐装等过程.     

ATP生物发光法测定啤酒酿造过程中污染微生物变化规律的研究

探讨了利用ATP生物发光微生物快速检测技术测定啤酒酿造过程中污染微生物数量的可行性。跟踪测定证明ATP法与显微镜镜检计数法测定结果有较高的一致性。利用ATP荧光检测技术跟踪酿造过程中微生物的变化,结合显微镜检法探索微生物的变化规律,为啤酒酿造过程污染微生物的控制提供新的检测方法和依据。     

加强酿造过程微生物控制提高啤酒口味纯净性

推行无菌化酿造，控制啤酒酿造过程的有害微生物是每个啤酒厂和工作者追求的目标。对酿造过程的微生物控制实际上主要是控制发酵过程的微生物，从沉淀槽的热麦汁冷却开始到啤酒灌装杀菌出酒的过程是微生物控制的关键环节。     

DISPOSAL OF EXCESS BREWER'S YEAST BY RECYCLING TO THE BREWHOUSE

Waste streams high in B.O.D. are produced by the brewing process itself. These wastes are wholesome but unwanted materials that were once part of or were in intimate contact with the brewing milieu. They are not inherently foreign to the process or the product, and disposal could be accomplished by recycling to the process. We have studied the effect on brewing processes and beer flavour of recycling waste yeast slurry to the mash mixer. Beer flavour is essentially unaffected by recycling, and of the brewhouse processes only lautering is slowed at higher recycle rates. Extract (up to 1% of the total) and soluble nitrogen can be recovered from the recycled yeast, but is strongly influenced by temperature during yeast storage and mashing. Worts made with recycled yeast tend to ferment more rapidly than normal worts and tend to have a lower end gravity.     

Enhancing the Microbiological Stability of Malt and Beer — A Review

While beer provides a very stable microbiological environment, a few niche microorganisms are capable of growth in malt, wort and beer. Growth of mycotoxin‐producing fungi during malting, production of off‐flavours and development of turbidity in the packaged product due to the growth and metabolic activity of wild yeasts, certain lactic acid bacteria (LAB) and anaerobic Gram negative bacteria, impact negatively on beer quality. It follows that any means by which microbial contamination can be reduced or controlled would be of great economic interest to the brewing industry and would serve the public interest. There has been an increasing effort to develop novel approaches to minimal processing, such as the exploitation of inhibitory components natural to raw materials, to enhance the microbiological stability of beer. LAB species, which occur as part of the natural barley microbiota, persist during malting and mashing, and can play a positive role in the beer‐manufacturing process by their contribution to wort bioacidification or the elimination of undesirable microorganisms. Other naturally occurring components of beer that have been valued for their preservative properties are hop compounds. It may be possible to enhance the antimicrobial activities of these compounds during brewing. Some yeast strains produce and excrete extracellular toxins called zymocins, which are lethal to sensitive yeast strains. Yeast strains resistant to zymocins have been constructed. Imparting zymocinogenic activity to brewing yeast would offer a defence against wild yeasts in the brewery. Thus, the antimicrobial properties of naturally occurring components of raw materials can be exploited to enhance the microbial stability of beer.     

微生物对麦芽品质的影响

大麦作为啤酒酿造的主要原料，其表面或外源的微生物在制麦过程中会影响麦芽的品质，并最终影响成品啤酒的质量。近年来研究发现在制麦过程中添加启动子培养物，既能作为微生物控制剂，抑制有害微生糖的生长；同时又能利用微生物分泌的水解酶系来提高麦芽的品质和安全性。本文介绍了麦芽中的微生物种类及其对麦芽质量的影响，并对添加不同启动子培养物对麦芽品质的改善及其工业化应用的可行性进行了探讨。     

Bioprotective potential of lactic acid bacteria in malting and brewing

Lactic acid bacteria (LAB) are naturally associated with many foods or their raw ingredients and are popularly used in food fermentation to enhance the sensory, aromatic, and textural properties of food. These microorganisms are well recognized for their biopreservative properties, which are achieved through the production of antimicrobial compounds such as lactic acid, diacetyl, bacteriocins, and other metabolites. The antifungal activity of certain LAB is less well characterized, but organic acids, as yet uncharacterized proteinaceous compounds, and cyclic dipeptides can inhibit the growth of some fungi. A variety of microbes are carried on raw materials used in beer brewing, rendering the process susceptible to contamination and often resulting in spoilage or inferior quality of the finished product. The application of antimicrobial-producing LAB at various points in the malting and brewing process could help to negate this problem, providing an added hurdle for spoilage organisms to overcome and leading to the production of a higher quality beer. This review outlines the bioprotective potential of LAB and its application with specific reference to the brewing industry.     

大豆酶解产物复合含氮糖浆用于啤酒发酵的研究

本文主要对大豆蛋白水解产物用于部分替代麦汁进行啤酒发酵的可行性进行了实验研究,并对发酵液的理化指标进行了检测分析.实验证明酵母在添加了大豆蛋白酶解液中的发酵液里可以正常发酵,所得啤酒各项指标均符合国家标准.     

发酵环境变化对酵母生长和成品啤酒的影响

啤酒发酵是一个复杂的生物和物质转化过程,在整个酿造过程中,从原料粉碎到开始发酵直至发酵结束降温冷贮,环境变量因素很多,会影响啤酒酵母生长,从而影响成品啤酒中的挥发性风味物质和啤酒品质。该文重点总结介绍麦汁浓度、接种率、发酵温度、压力变量对发酵过程的影响,旨在为解决啤酒酿造过程可能出现的问题提供一些思路,从而提高啤酒质量。     

啤酒腐败菌的检测技术研究进展

啤酒腐败菌会影响啤酒的质量和安全,因此,啤酒生产过程中腐败菌的检测尤为重要。传统的培养基检测方法简单、易操作且准确性强、但耗时较长。随着现代啤酒工业和分子生物学技术的不断发展,快速、灵敏的检测技术层出不穷,如改进后的培养基法、生化发光检测法、基于PCR的检测方法、基于核酸杂交的检测方法和基质辅助激光解吸电离飞行时间质谱等。本文从方法、原理、优缺点等多个方面总结和阐述啤酒腐败菌的检测方法,以期为啤酒生产过程中高效、准确的检测腐败菌提供参考。     

A Review: The Role of Barley Seed Pathogenesis‐Related Proteins (PRs) in Beer Production

Pathogenesis‐related proteins (PRs) are involved in the protection of dormant and germinating cereal seeds against pathogenic microorganisms and pests. Moreover, barley grain PRs have considerable technological importance in the brewing of beer. The compact structure of PRs allows them to survive the hostile conditions of the extracellular compartments, where they are usually localized, and enables the endurance of certain classes of PRs during the harsh conditions of the technological steps of beer production. Beer proteome maps reveal a dominant presence of PRs and facilitate association between particular proteins and specific beer quality traits. Current knowledge on the influence of PRs on the various aspects of beer quality has been summarized in this review.     

Comparison of beer quality attributes between beers brewed with 100% barley malt and 100% barley raw material

BACKGROUND: Brewing with 100% barley using the Ondea^® Pro exogenous brewing enzyme product was compared to brewing with 100% barley. The use of barley, rather than malt, in the brewing process and the consequences for selected beer quality attributes (foam formation, colloidal stability and filterability, sensory differences, protein content and composition) was considered. RESULTS: The quality attributes of barley, malt, kettle‐full‐wort, cold wort, unfiltered beer and filtered beer were assessed. A particular focus was given to monitoring changes in the barley protein composition during the brewing process and how the exogenous OndeaPro^® enzymes influenced wort protein composition. All analyses were based on standard brewing methods described in ASBC, EBC or MEBAK. To monitor the protein changes two‐dimensional polyacrylamide gel electrophoresis was used. CONCLUSION: It was shown that by brewing beer with 100% barley and an appropriate addition of exogenous Ondea^® Pro enzymes it was possible to efficiently brew beer of a satisfactory quality. The production of beers brewed with 100% barley resulted in good process efficiency (lautering and filtration) and to a final product whose sensory quality was described as light, with little body and mouthfeel, very good foam stability and similar organoleptic qualities compared to conventional malt beer. In spite of the sensory evaluation differences could still be seen in protein content and composition. Copyright © 2011 Society of Chemical Industry