不同发酵方法生产100%大麦啤酒饮料的研究

本文研究了利用诺维信公司Ondea Pro?酶进行100%大麦啤酒饮料的生产。分别利用上面发酵法与下面发酵法进行100%大麦啤酒饮料的生产,酿造而成100%啤酒饮料,并对其麦汁糖谱组成、氨基酸含量、蛋白质隆丁区分、α-氨基氮含量、啤酒风味物质等指标进行了全分析,特别是对上面发酵的特色风味物质4VG进行了检测,最后邀请国家级品酒委员进行了感官品评。研究发现,利用Ondea Pro?酶生产的麦汁,完全能够为酵母提供足够的营养物质,从而生产出令人满意的啤酒饮料。而上面发酵法生产的100%大麦啤酒饮料,由于采用了独特的酵母菌种和较高的发酵温度,其风味物质含量远高于下面发酵法,品评口感也远胜于下面发酵法生产的产品。上面发酵法生产的100%大麦啤酒饮料具有极大的市场潜力,是极具推广价值的一款啤酒饮料。     

安徽轻工化学厂JPI酒精生产工程特点

ＪＰＩ为芬兰雅哥贝利国际公司的简称,安微轻工化学厂与其合作建成的ＪＰＩ酒精生产工程的主要特点是低温液化;连续发酵,成熟醪含酒精达１２％,由５个发酵罐和１个缓冲罐组成,总发酵时间最多５５小时,双塔差压蒸馏,产品达到食用酒精标准,有的指标达优级酒精标准。     

双轮底发酵过程中酒醅温度变化规律的探讨

温度对窖池酒醅发酵过程有着极为重要的影响,酒醅在发酵过程中的温度变化主要是环境温度、酒醅入窖温度及窖池微生物生长代谢三者共同作用的结果。该试验利用窖池温度检测系统对成都某酒厂采用浓香型白酒双轮底工艺的三口窖池酒醅温度进行实时精确检测,并绘制出其温度变化曲线。结果发现：采用双轮底工艺时,酒醅温度变化基本符合“前缓、中挺、后缓落”的传统经验,相比于普通工艺,双轮底酒醅温度变化更为平缓。     

一种剑杆织机剑带冷却装置的设计

介绍了剑杆织机剑带及相关零件在使用过程中产生热量而造成磨损,影响其使用寿命,针对冷却装置的磨损,对冷却装置材料及表面涂层的几个设计方案作了对比分析。结果表明,冷却装置以铝合金为材料,表面采用陶瓷涂层,设计成可拆卸结构,可使冷却装置的使用寿命延长。最后对新型纳米涂层在纺机零部件中的应用进行了展望。     

提高北方浓香型白酒质量的研究

辽宁西北地区的风大干燥、水质欠佳及冬夏温差太大等自然条件,不利于酿酒微生物的生长繁殖,致使浓香型白酒的品质存在某些欠缺。试验中,利用多粮发酵巧妙地添加大麦芽;借用酱香型白酒窖外高温堆积工艺;提高双轮底发酵温度等措施,克服了自然不利条件,使北方浓香型酒复合香气更加浓郁,品质大幅提升。     

RAPID BEER PRODUCTION AND CONDITIONING USING A PLUG FERMENTOR

Beer has been produced very rapidly, with residence time of less than 1 hour, by passing wort continuously through a plug formed from a yeast/kieselguhr mixture. Using malt wort the total output from the fermentor is limited by gradual blockage of the plug; nevertheless output is high per unit of yeast used. Prolonged operation is possible using nitrogen-free sugar solutions. The properties of beer produced from normal wort vary over the period of operation of the fermentor and blending is required to give a constant product. The average pH and nitrogen content of the beer is high if conventional wort is used but can be reduced to normal levels by control of wort composition. Details of a procedure for controlling the content of diacetyl and 2,3-pentane-dione in the beer are described and the potential value of a yeast-plug unit for beer conditioning is discussed.     

CONTAMINATION OF IMMOBILIZED YEAST BIOREACTORS

Microbiological contamination of immobilized yeast bioreactors for lagering of beer was studied. Four common brewery contaminants and two contaminants isolated from the continuous processing system were tested for their ability to survive and grow in the packed bed DEAE-cellulose bioreactors. Bacterial contaminants were washed out within less than six weeks without causing any alterations in the flavour composition of the beer. The initial contamination levels were 10⁴–10⁶ cells ml^?1. Gram positive lactic acid bacteria, Lactobacillus brevis and Pediococcus damnosus, were more persistent than a Gram negative wort bacterium, Enterobacter agglomerans. The wild yeasts Saccharomyces cerevisiae (ex. diastaticus) and Candida krusei were the most persistent contaminants and the only ones able to grow in the reactors. Another wild yeast, Rhodotorula rubra, did not survive in competition with brewer's yeast and was washed out within a few weeks. C. krusei and R. rubra were previously isolated from a spontaneously contaminated system. None of the contaminants caused formation of phenolic or other off-flavour compounds in detectable levels.     

THE ROLE OF DIMETHYL SULPHOXIDE REDUCTASE IN THE FORMATION OF DIMETHYL SULPHIDE DURING FERMENTATIONS

The ability to produce dimethyl sulphide (DMS) during fermentation of wort is apparently a general characteristic of Saccheromyces cerevisiae and Saccharomyces uvarum. Washed suspensions of these yeasts reduce dimethyl sulphoxide (DMSO) but there is no correlation between DMS formation in fermentation and DMSO reduction in whole cells. Although different strains vary widely in their ability to reduce DMSO they all contain similar levels of NADPH—dependent DMSO reductase. This enzyme is a multi-protein system which closely resembles methionine sulphoxide reductase. Spoilage bacteria including Enterobacter cloacae can reduce DMSO more efficiently than can yeast probably because a different enzyme system is involved.     

包装机行程机构的创新设计

本文介绍了作者设计的一种手电两用包装机,并通过对其主压板行程的工作原理和运动分析等研究,为6面体挤压型包装机的设计提供了新的理论和方法。     

聚酯切片厂2000M3乙二醇贮罐设计及制造

乙二醇贮罐的设计和制造既有一般化工油罐的普遍性,又有其特殊性.要在保证满足生产工艺要求的前提下,力求安全、经济.本文就乙二醇贮罐设计及制造加以总结概述.     

酒鬼酒生产中双轮底夹泥发酵工艺

取上轮发酵正常的底槽1.8m^2左右,不蒸馏,加入大曲粉20kg左右,酒尾6～8kg,拌匀入窖发酵。控制水分64%～65%,入窖酸度2.8～3.5,入窖温度春冬16～18℃,夏秋平地温或低于地温,淀粉含量9%～10%,可加入10kg左右糖化料调整淀粉含量。双轮底入窖底后踩紧,上覆盖5cm厚的优质窖泥,再覆糟醅发酵48天左右出窖蒸馏。试验结果表明,夹泥发酵双轮底酒中的已酸乙酯含量达398～442.5mg/100ml,窖香明显,酯香突出。     

包装机主执行机构的设计与机构运动分析

探讨了设计包装机主执行机构的选型原则；应用机构学理论，采用罗列比较法，并结合新产品设计，开发了一个主执行机构的选型方案，并对机构运动进行了分析，为产品设计提供了一种新的设计理论和方法。     

上面发酵高粱啤酒的工艺研究

高粱啤酒作为一种营养丰富、口感独特的无麸质酒精饮料,具有广阔的发展前景。为研制品质优良的高粱啤酒,本研究以高粱芽为原料,分别对糖化工艺对高粱汁中总还原糖和α-氨基氮量的影响;发酵工艺对高级醇含量的影响以及发酵后不同澄清剂对高粱啤酒的澄清效果和色度的影响进行了研究。结果表明:高粱汁制备的最佳糖化方法为倾出糖化法,糖化条件为:浸酶温度35℃,浸酶时间20 min,糊化温度90℃,糊化时间30 min,糖化温度65℃,糖化时间1 h,糖化后高粱芽汁的总还原糖含量为83.23 g/L,α-氨基氮含量适中,为180.8 mg/L。高粱啤酒的最佳发酵条件为:高粱芽汁浓度12°P、酵母菌接种量2.0×107个/m L、发酵温度16℃,发酵后啤酒中的高级醇含量为109.09 mg/L,该条件可有效降低高级醇含量。最佳的澄清剂为皂土,当添加比例为0.9%时,透光率达到90%,高粱啤酒的澄清效果最佳。在此工艺条件下,酿造出的上面发酵高粱啤酒澄清透明、色泽鲜亮、口感独特,高级醇含量适宜,是一种风味独特的新型酒精饮品。     

STORAGE OF PITCHING YEAST FOR PRODUCTION OF WHISKY

The viability of pitching yeast stored at 5°C and at 20°C was compared. The viability of the yeast stored at 5°C was about 80% after 54 d storage and its CO₂ producing activity also remained high. The ethanol production rate of yeast stored for a long period at 5°C was unaffected in a subsequent fermentation test, even though the viability was only about 50%. The ethanol production rate of yeast stored at 20°C decreased in proportion to a rapid decrease in viability during storage. The concentration of intracellular sulphur compounds, important for the production of aromatic components of whisky, of yeast stored at 5°C was higher than that of yeast stored at 20°C. Therefore, the storage of yeast at 5°C seems appropriate for production both of ethanol and aroma.     

FUNDAMENTALS OF IMMOBILISED YEAST CELLS FOR CONTINUOUS BEER FERMENTATION: A REVIEW

Recent fundamental research conducted on immobilised cells with a focus on continuous primary beer fermentation is presented in this review. The knowledge of whole-cell immobilisation, continuous fermentation, yeast biochemistry associated with beer flavour production, and bioreactor engineering design is required to apply immobilised yeast cells for industrial scale beer production. Understanding how immobilisation and continuous bioreactor operation affect yeast cell metabolism and viability will provide the groundwork for optimising beer quality. The latest studies on immobilised cell carriers, viability, vitality, mass transfer characteristics and bioreactor design indicate that an industrial scale immobilised cell system for primary beer fermentation may soon be a reality in the modern brewery .     

THE REDUCTION OF DIMETHYL SULPHOXIDE TO DIMETHYL SULPHIDE DURING FERMENTATION

Dimethyl sulphide (DMS) produced by yeast during fermentation is formed from dimethyl sulphoxide (DMSO) rather than from S-methyl methionine (HADMS). All the yeasts and one of the two spoilage organisms examined formed DMS from DMSO. In fermentations at 8°C only 13–21% of the DMSO is reduced to DMS by yeast and the extent of conversion is greatly decreased by raising the fermentation temperature. The amount of DMS formed increases as the gravity of the wort is raised but is also dependent on the fermentable sugar employed. There is therefore no simple correlation between DMSO content of the wort and DMS formation.     

OCCURRENCE OF A KILLER STRAIN OF SACCHAROMYCES CEREVISIAE IN A BATCH FERMENTATION PLANT

A killer strain of Saccharomyces cerevisiae has been isolated from batch fermented beer which had attenuated poorly and possessed an unpleasant phenolic (clove-like) aroma.     

移动式液压倒纸机的设计

本文介绍了利用液压传动和电气自动控制方案设计出的全桥式晾纸机上使用的全自动倒纸机。该机结构简单,运行平稳,应用范围广泛,且可大大提高生产率和晾纸的质量。     

Mozzarella干酪拉伸机的设计

描述一种用于生产Mozzarella干酪的单螺杆拉伸机的设计,包括理论分析、机械设计以及试验论证.该拉伸机可以实现对凝乳颗粒的可控加热与拉伸,同时,为了直接获得直径20 mm～30mm的干酪块,在拉伸机出口处安装了小孔均匀分布的挤出板,使小尺寸的干酪块冷却时间缩短.该机试制的样品符合美国农业部关于Mozzarella干酪产品的标准.