麦汁混浊原因及主要解决措施

麦汁产生混浊的原因主要有原料（麦芽、大米、玉米、酒花）质量、原料粉碎度、糖化工艺、过滤条件（入醪刀速、阀门开度、耕糟刀高度）、煮沸条件（煮沸强度、麦汁pH、煮沸时间）、回旋沉淀效果等。解决麦汁混浊的主要措施：包括提高麦芽、辅料以及酒花的质量;控制麦芽和辅料的粉碎度;控制糖化工艺、麦汁过滤洗糟和麦汁煮沸条件及沉淀冷却效果。（孙悟）     

供酿造黑啤用的麦汁生产方法

该方法涉及生产一种供酿造啤酒用浅色麦芽汁的糖化醪。其法是先添加着色剂、糖化、过滤后使含有酒花的麦芽汁煮沸。为了提高萃取物产量，降     

单锅高效糖化法研究

糖化方法有多种:煮出糖化法、浸出糖化法、双醪糖化法。目前,国内糖化工艺一般都采用双醪浸出糖化,两锅操作,糊化醪并入糖化锅后,不再分醪煮沸,在糖化锅内直接升温糖化。相比,此工艺糖化周期短、麦皮中多酚物质、麦胶物质等溶出少,色度低,适合淡爽啤酒的生产。但到目前为止,国内啤酒生产过程中糊化和糖化醪尚无在一锅进行之先例。单锅高效糖化法,就是打破常规,糊化、液化、糖化过程在一锅完成,此工艺无论在降低成本、改善麦汁质量,还是在简化操作方面都有独到之处;糊化下料水温可提高到75℃以上,不经煮醪。     

试谈采用传统设备合理缩短发酵周期

几项主要技术措施一、制备组成良好的麦汁1.麦芽搭配使用麦芽分级存放,投料时,根据不同品种、酒型,选用不同的麦芽,按照色度、糖化力、α—氨态氮等指标,常常是两种或三种搭配使用,实践证明,这是制备组成良好麦汁的重要措施。2.采用双醪煮出浸出糖化工艺此法对含酶的麦芽不进行煮沸,只煮沸米醪、混合醪液全部经过63℃、70℃的最适作用温度,升温缓慢,生化反应充分,可发酵性糖、可溶性氮均能得到提高,麦汁的最     

使用格瓦斯麦汁酿造黑啤

该方法涉及生产一种供酿造黑啤酒用浅色麦芽汁的糖化醪。其法是糖化、过滤，使含有酒花的麦芽汁煮沸，添加着色剂。为了改善麦芽汁和啤酒的质     

11°全麦芽淡色啤酒酿造工艺

1.关于全麦芽啤酒定义:全麦芽啤酒就是不添加任何辅料,完全以麦芽为原料,经糖化、麦汁过滤、煮沸并加酒花,经冷却、发酵、贮存而成的啤酒。全麦芽啤酒的特点:具有更加明显、浓郁的麦芽、酒花香味;口感爽适、醇厚、杀口力强;相对于辅料啤酒,其酒体呈金黄色;泡沫特性十分优越。2.生产工艺控制2.1 原料选用:①宜选用溶解度较好的麦芽,煮沸色度应小于     

缩短麦汁过滤时间的探求

麦汁糖化过程结束后,麦芽和辅料中大分子颗粒的分解已完成,此时,应迅速将糖化醪液中已溶解的可溶性物质和不溶性物质分离,以得到澄清麦汁。将醪液中麦汁和麦糟进行分离,称为过滤洗糟,想要缩短麦汁过滤的时间,就必须考虑影响麦汁过滤的因素有哪些,比如麦芽粉碎质量、醪液糖化效果、过滤槽结构、洗糟方法控制等等。     

啤酒酿造过程中有机酸的研究

研究不同的糖化工艺对麦汁中有机酸含量的影响。通过改变原料状况（不同的辅料比、粉碎度）、糖化水pH、糖化温度、糖化时间等工艺参数,发现麦汁中的有机酸主要来自麦芽呼吸产生的酸,糖化过程中的酶解作用几乎不产生有机酸,且麦芽原始酸和总有机酸含量之间具有较好的线性关系（R^2=0．943）。麦汁煮沸时添加酒花和钙离子,可以使麦汁中的有机酸含量下降10％。     

影响啤酒风味稳定性的工艺因素

<正> 虽然啤酒风味的稳定性主要取决于瓶装啤酒的氧含量,但是麦芽汁生产的各个步骤也具有同样的重要性。即: 1.在麦芽糖化、麦芽汁过滤和煮沸过程中,防止氧的吸入,保护还原性物质。 2.通过糖化醪和麦芽汁的彻底分离操作,去除易于与风味活性物质,如羰基类化合物     

10°P淡爽型浓色啤酒的研制

本试验以小麦和大米为辅料，采用焙焦小麦芽调节啤酒色度，经过双醪一次煮出糖化法糖化和低温发酵成功地酿制出１０°Ｐ淡爽型浓色啤酒，该产品色呈红褐色或宝石红色，泡洁细腻，挂标，有明显小麦芽焦香味，苦味较轻，口味清爽，纯正，经济效益和社会效益明显。     

Effect of mashing procedures on brewing

The effect of the double decoction mashing method (method A) and the single decoction plus infusion mashing method (method B) on brewing were compared. The trials were carried out with the same raw material (malt and a minor amount of corn as adjunct) on an industrial-scale plant. The effects of mashing methods A and B were evaluated in wort and beer samples obtained with the high gravity system. The analytical parameters of the worts and beers produced and the economic aspects of production (yield, beer quality, time and energy) were discussed. The results showed no considerable differences in beer quality, while a significant difference was observed in the composition of fermentable sugars of worts. Method B gave a wort with a higher content of fermentable sugars which were converted to alcohol during fermentation; therefore, it allowed to obtain a higher beer volumetric yield of the same quality while saving time and energy.     

THE INFLUENCE OF MASHING CONDITIONS ON WORT AND BEER QUALITY

From a comparison of the performance of ale and lager malts mashed by constant temperature infusion, by temperature programmed infusion, and by decoction procedures it emerges that malt modification and the pattern of kilning are as important in determining the composition of wort as are the mashing conditions. Worts with appropriate levels of amino and total nitrogen and of fermentable sugars may be obtained by selecting lightly-dried well-modified malts and mashing with a constant temperature infusion rather than by using less modified malt in conjunction with more complex mashing programmes. Ale malts yield worts of lower pH which is reflected in a slight reduction in hop utilization. Head retention is improved by the use of undermodified malts but colloidal stability is improved when well-modified malts are used. In the case of well-modified malts a high final curing temperature is not a prerequisite for achieving good colloidal stability in beer.     

Effect of varying starch properties and mashing conditions on wort sugar profiles

The aim of this research was to investigate the relationship between starch composition in barley and its malted counterpart alongside malt enzyme activity and determine how these factors contribute to the fermentable sugar profile of wort. Two Australian malting barley varieties, Commander and Gairdner, were sourced from eight growing locations alongside a commercial sample of each. For barley and malt, total starch and gelatinisation temperature were taken, and for malt, α‐ and β‐amylase activities were measured. Samples were mashed using two mashing profiles (infusion and Congress) and the subsequent wort sugar composition and other quality measures (colour, original gravity, soluble nitrogen) were tested. Variety had no significant (<0.05) effect on any barley, malt, enzyme or wort characteristics. However, growing location impacted gelatinisation temperature, colour, malt protein content and original gravity. The gelatinisation temperature in malt samples was higher, by ~0.8°C, than in the equivalent barley sample. Several malt samples, even with protein contents <12.0%, had gelatinisation temperature >65°C. The fermentable sugars measured in the malt prior to mashing showed a higher proportion of maltose than glucose or maltotriose. In addition, there were significant differences in the amount of sugar produced by each mashing method with the high temperature infusion producing a higher amount of sugar and proportionally more maltose. There is scope for further research on the effect of genetics and growing environment on gelatinisation temperature, mash performance and fermentable sugar development. Routinely measuring gelatinisation temperature and providing this information on malt specification sheets could help brewers optimise performance. © 2019 The Institute of Brewing & Distilling     

Effect of malting time,mashing temperature and added commercial enzymes on extract recovery from a Nigerian malted yellow sorghum variety

Preliminary microbiological studies carried out on sorghum grains showed that the major microorganisms found were mainly bacteria and that aflatoxin‐producing fungi were not found. The effect of added commercial enzyme preparations and different infusion mashing temperatures on extract yield, from sorghum malted at 30 °C, was studied. The infusion mashing method (65 °C) developed for mashing well‐modified barley malt produces poor extract yields with sorghum malt. The extract yield from the sorghum malt in this study was very low with infusion mashing at 65 °C, without the addition of commercial enzyme preparations. A higher extract yield was obtained from the sorghum malt, without the commercial enzyme addition, when using infusion mashing at 85 °C. Both infusion mashing temperatures (65 and 85 °C) showed an improved extract yield over the control malt when commercial enzyme preparations were used during mashing of the sorghum malt. The added enzyme preparations resulted in a higher extract yield from the germinated sorghum when infusion mashing was performed at 65 °C over mashing at 85 °C. The use of individual commercial enzymes (α‐amylase, β‐glucanase, protease, xylanase, saccharifying enzyme and combinations of some hydrolytic enzyme) increased extract yields, when complemented with the enzymes that had developed in the sorghum malt. Copyright © 2016 The Institute of Brewing & Distilling     

啤酒糖化生产过程预测统计数学模型的研究

本文对啤酒生产糖化过程预测统计数学模型的建立进行了研究。首先采用正交拟因子试验设计法,对不同质量的麦芽确定对麦芽汁质量具有显著影响的因素,并得出了二次煮出糖化法最佳工艺条件。在此基础上建立了麦芽汁主要质量指标与不同质量的麦芽和其它影响因素之间关系的预测统计数学模型。通过实验验证,模型的预测精度较高。     

ROLE OF ALPHA-GLUCOSIDASE IN THE FERMENTABLE SUGAR COMPOSITION OF SORGHUM MALT MASHES*

The cause of the high glucose to maltose ratio in sorghum malt worts was studied. Mashing temperature and pH strongly affected both the amount of glucose and the proportion of glucose relative to total fermentable sugars. The relative proportion of glucose was higher when mashing was performed. at pH 4.0, close to the pH optimum for sorghum alpha-glucosidase, than at the natural pH of the mash (pH 6.0–5.5). Mashing according to the EBC procedure using an enzymic malt extract with pre-cooked malt insoluble solids producing a wort containing maltose and glucose in an approximately 4:1 ratio, whereas mashing with a malt extract without pre-cooking the malt insoluble solids resulted in a wort with approximately equal amounts of maltose and glucose. Both treatments gave the same quantity of total fermentable sugars and amount of wort extract. Sorghum alpha-glucosidase was confirmed to be highly insoluble in water. All or virtually all activity was associated with the insoluble solids. Hence, it appears that the high amount of glucose formed when sorghum malt is mashed conventionally is due to alpha-glucosidase activity. Pre-cooking the malt insoluble solids inactivates the alpha-glucosidase, preventing the hydrolysis of maltose to glucose.     

Studies on the mashing conditions of teff (Eragrostis tef) malt as a raw material for lactic acid‐fermented gluten‐free beverage

Formation of extracts and fermentable sugars during mashing can be limited by incomplete starch gelatinisation. The aim of this research was to develop mashing programme for 100% teff malt as a potential raw material for gluten‐free lactic acid‐fermented beverage. Isothermal mashing at temperatures ranging between 60 and 84 °C was conducted, and the highest extract (85%) was observed for the wort samples produced at temperatures higher than 76 °C. Sixty‐minute rest at 71 °C resulted in higher fermentable sugars than other tested conversion rest temperatures. Inclusion of lower mashing‐in temperature in the mashing programme also substantially improved the concentrations of free amino nitrogen (128 mg L^?1) and fermentable sugar (58 g L^?1) in the final wort. Therefore, 30‐min rest at 40 °C followed by 60‐min rest at 71 °C and 10‐min rest at 78 °C was found to be a suitable mashing programme for teff malt.     

Influence of sorghum grain type on wort physico‐chemical and sensory quality in a whole‐grain and commercial enzyme mashing process

To determine the most suitable types of sorghum for whole‐grain adjunct in lager beer brewing, 14 cultivars of five different types: white tan‐plant, white non‐tan‐plant, red non‐tannin, white tannin (type II) and red tannin (type III) were evaluated. The effects of grain type on wort physico‐chemical and sensory quality with raw grain and malt plus commercial enzyme mashing were assessed. Tannin content correlated significantly and negatively with wort extract and fermentable sugars (p < 0.001) and free amino nitrogen (FAN; p < 0.1). This is attributable to inactivation of the exogenous enzymes by the tannins during the mashing process. However, the type II tannin sorghums had wort quality attributes closer to the non‐tannin sorghum types, probably owing to their relatively low tannin content (≤1%). Malting gave a great improvement in wort extract, fermentable sugars and FAN, but substantially influenced wort sensory properties in terms of higher sourness, bitterness and astringency, as well as the expected more malty flavour. Worts from raw red non‐tannin sorghums were similar to those of white tan‐plant sorghums in both physico‐chemical and sensory quality. Thus, red non‐tannin sorghums, in view of their better agronomic quality, have considerable potential as a whole‐grain adjunct in lager beer brewing. Copyright © 2013 The Institute of Brewing & Distilling     

Validation and application of osmolyte concentration as an indicator to evaluate fermentability of wort and malt

The objective was to develop a new simple and quick approach to predict fermentability, based on osmolyte concentration (OC). Eight malts were assayed for diastatic power, starch‐degrading enzymes [α ‐amylase, β ‐amylase and limit dextrinase (LD)] and malt OC (MOC). All malts were mashed to determine wort OC (WOC), real degree of fermentation (RDF) and sugar contents in a small‐scale mashing protocol. The results showed that MOC was correlated with malt α ‐amylase, LD, the resultant WOC, RDF and fermentable sugar (r  = 0.813, 0.762, 0.795, 0.867, 0.744, respectively), suggesting that MOC was discriminating in predicting levels of malt amylolytic enzymes, wort sugar and RDF without the mashing and fermentation process. Moreover, WOC showed stronger correlations with malt α ‐amylase, LD, RDF and fermentable sugars (r  = 0.796, 0.841, 0.884, 0.982, respectively), suggesting that WOC can be used to quickly predict wort sugar contents and RDF without a fermentation step. Furthermore, the effects of mashing temperature and duration on WOC, RDF and sugar contents are discussed. Adjusting mash temperature to 65°C or extending the mash duration dramatically increased RDF and WOC, whereas malt extract was relatively stable. Similarly, WOC showed significant correlations with RDF and fermentable sugars (r  = 0.912 and 0.942, respectively), suggesting that WOC provides a simple and reliable tool to assist brewers to optimize mash parameters towards the production of ideal wort fermentability. In conclusion, the ability of OC to predict malt fermentability and sugar content allows brewers to keep better control of fermentability in the face of variation of malt quality, and to quickly adjust mashing conditions for the consistency of wort fermentability. Copyright © 2017 The Institute of Brewing & Distilling     

Carbohydrate content and structure during malting and brewing: a mass balance study

A holistic view of the fate of barley starch, arabinoxylan and β-glucan throughout malting and brewing is largely missing. Here, an industrial scale malting trial and pilot brewing trial were performed, and the concentration and structural characteristics of carbohydrates were analysed at 28 key points in the process. The barley starch content decreased during malting from 75.0% to 69.7%. During mashing, malt starch was converted to fermentable sugars (75.3%), dextrin (22.8%) or was retained in spent grains (1.8%). Arabinoxylan was partially hydrolysed during malting. Despite mashing-in at 45°C, no further solubilisation of arabinoxylan was observed during mashing. However, the average degree of polymerisation of the soluble arabinoxylan fraction decreased slightly. During fermentation, the arabinoxylan content decreased to 2.5 g/L. The amount of barley β-glucan decreased gradually in time during malting. Of the solubilised β-glucan, 31% was retained in the spent grains during wort filtration, slightly lowering the β-glucan content in the wort. The β-glucan content remained at 0.5 g/L during fermentation. Sucrose was hydrolysed during mashing, probably by barley invertases. From the total amount of malt used, 41.0% was converted to fermentable sugars. This mashing yield could have been improved by the full hydrolysis to fermentable sugars of the present β-glucan (to 41.1%), the remaining starch in spent grains (to 42.0%) and dextrin in wort (to 50.3%). These results provide more insight into the carbohydrate conversions during malting and brewing and can act as a baseline measurement for future work. © 2020 The Institute of Brewing & Distilling