【作者】 李凤；

【导师】 周广田；

【作者基本信息】 山东轻工业学院 ， 发酵工程， 2008， 硕士

【摘要】 近年来,随着许多新型啤酒如纯生啤酒、无醇啤酒等的日益流行,啤酒的泡沫问题也日益突出——泡沫不细腻、附着力差等,急需改善。由于工艺改进有一定的局限性,因此主要措施是添加泡沫增强剂。而目前市面上销售的泡沫增强剂多为化工产品,存在一定的安全隐患,添加泡沫增强剂对啤酒的稳定性造成了威胁,因此急需研究一种纯天然的啤酒泡沫增强剂来解决啤酒泡沫与稳定性的问题。本论文首先通过实验,分析比较了啤酒原液,啤酒泡沫及泡沫残液中蛋白质,尤其是高分子蛋白质(MW>5,000Da)的含量分布,结果显示泡沫稳定性与高分子蛋白质具有比低分子蛋白质更高的相关性。从凝胶色谱分析可以看出,泡沫蛋白主要为分子量10000Da,40000Da左右的高分子蛋白质,验证了分子量5000Da以上的高分子蛋白质与泡沫稳定性的密切相关性和高度重合性。本文研究了大麦、小麦、大麦芽等原料的特性,并结合原料的优缺点进行原料的组合搭配,确定使用大麦与大麦芽的组合或小麦与大麦芽的组合;对原料进行粉碎、糖化、真空浓缩等工艺,生产出一种纯天然的、60°P的、高浓、高生物稳定性的啤酒泡沫增强剂。并通过试验,确定了特殊的糖化工艺参数。对本产品的分析结果显示,其主要成分为糖蛋白,与啤酒泡沫主要的作用物质相同。通过SDS变性凝胶电泳图可以看出,产品蛋白质分子量主要在40000 Da与15000Da左右,而这两部分正是被普遍认为在啤酒泡沫中起作用的蛋白质。进一步对产品的应用进行试验,产品使用量视具体啤酒质量情况来定。产品对啤酒,尤其是本身泡沫质量差的啤酒,促泡效果明显。由于其主要原料也可作为啤酒生产的主要原料,所以它的组成与麦汁组成相似,添加到啤酒后,不会破坏啤酒的平衡体系,也不会影响啤酒的口味。通过试验确定,添加有啤酒泡沫增强剂的啤酒稳定性极高。另外,它是天然绿色产品,符合食品卫生要求,使用方便,便于计量,是极具开发价值的产品。更多还原

【Abstract】 In recent years, with many new kinds of beer becoming increasingly popular such as unpasteurized beer, alcohol-free beer and so on, the beer foam problem - foam not exquisite, poor foam adhesion etc., is also day by day prominent in urgent need of improvement. Because the limitation on technically improvement, the beer foam intensifier become the major choice. At present, most of foam intensifier on the market belongs to chemical, and these products could bring some safety problems and could have impact on the beer stability. So a natural beer foam intensifier is urgently needed to resolve the problem of beer foam and stability.In this paper, firstly we analyzed and compared the contents of total protein, especially the high-molecular weight proteins (MW>5,000Da) of original beer, liquid from beer foam and the rest liquid after foaming by experimental measurement. The results showed that the high-molecular weight proteins had higher linear relativity to beer foam stability than the low-molecular weight proteins. In the gel chromatographic study, most of the foaming proteins appeared to be MW 10000Da or 40000Da, verifying that the close relationship and high coherence between high-molecular weight proteins (MW>5,000Da) and beer foam performance.In this study, the properties of barley, wheat and malt were examined, and proper combinations were conducted according to the character of materials. By use of the combination of malt with barley or malt with wheat, smash, saccharification and vacuum concentration, a natural, 60°P, high-concentration, high biological stability beer foam intensifier was produced, and the specific saccharification technological parameter was determined.The analysis of this product showed that its main component was glycoprotein, as same as the beer foam. It was also shown that the molecular weight of product protein was around 40000Da or 15000Da in the SDS gel chromatography, and these two parts are generally considered to be effective proteins in the beer foam.Further product testing for application indicated that the amount of use depended on the special details of beer. The product could promote frothiness evidently for beer especially for ropy beer in foam. Because of its major materials also can be used as the main raw material for beer production, so its composition is similar with that of the wort. After adding this product into beer, it will not disrupt the balance system and affect the taste of the beer. The experiment confirmed that the beer added by this beer foam intensifier had high stability. In addition, it is a natural green product, in line with the food hygiene requirements, ease of use, ease of measurement, and it is of great value for development.更多还原