糖化麦汁生产中TBA值控制研究

啤酒TBA值能够有效直接的反应啤酒的老化程度,糖化麦汁作为啤酒发酵的原材料,麦汁TBA值将直接影响到啤酒的TBA值。对糖化麦汁生产中影响TBA值的因素进行了研究,确定降低麦汁TBA值的措施。     

麦汁煮沸工艺条件的优化

从麦汁煮沸过程中TBA值的改变、麦汁中可凝固氮的改变、酒花α-酸异构化率3个方面来论述麦汁煮沸对啤酒酿造质量的影响.     

麦汁煮沸工艺的优化试验

麦汁煮沸是啤酒酿造的重要工序之一，影响啤酒的口味和非生物稳定性。通过提前麦汁初沸时间、缩短麦汁总煮沸加热时间，对麦汁煮沸工艺进行优化，在保证啤酒非生物稳定性的前提下，改善啤酒口味，降低资源消耗。     

优化麦汁煮沸条件,提高麦汁质量

麦汁煮沸过程中TBA值有很大的改变,麦汁可凝固氮、酒花α-酸异构化率等也有所变化。本文拟从三个方面来论述麦汁煮沸对啤酒酿造质量的影响,在总结试验结果的基础上,提出优化麦汁的煮沸条件。     

低压煮沸工艺降低麦汁中可凝固氮含量

采用低压煮沸工艺，可提高煮沸麦汁温度至100．5℃，加强蛋白质凝聚，麦汁可凝固氮下降0．5mg／100mL；煮沸过程加强了美拉德反应、“棕色反应”，类黑精、类黑素化合物增加，麦汁色度增加，麦汁的抗氧化能力增强；煮沸强度从9％～12％降至7％～8％，煮沸时间缩短10～20min，提高生产效率，节约能源20％；改善啤酒非生物稳定性。（孙悟）     

麦汁缓冲性能对啤酒酵母高级醇生成量的影响

在麦汁主要成分给定的情况下，水质、外加酸以及麦汁煮沸时间是影响麦汁缓冲容量的重要因素，缓冲容量愈大，高级醇含量愈高。结果表明：pH5．0的酸水糖化效果较好；较大缓冲容量的水质有利于麦芽的糖化；盐酸、磷酸和乳酸的使用能提高麦汁的缓冲容量；充分的煮沸可使其缓冲容量降低30％以上；麦汁的缓冲容量对啤酒中高级醇浓度有较大的影响，可以通过控制麦汁的缓冲容量来实现对发酵过程pH的控制。     

啤酒中SO2与TBA的变化关系研究

研究了TBA值与二氧化硫指标在酒体老化过程中的变化关系。表明了酒体中大部分二氧化硫的损失是其本身的氧化作用，其次才是与部分羰基化舍物结合。TBA值的适用性方面，我们认为其比较适合新鲜啤酒的老化物质与趋势的分析，对于老化后的啤酒比较不适舍。本文又研究了TBA值与二氧化硫指标在麦汁煮沸、发酵过程中的变化情况。     

麦汁煮沸工艺对凝固氮含量的影响

延长煮沸时间和增加煮沸温度可降低麦芽汁凝固氮含量，但会增加麦汁色度；单宁的理想添加浓度为60mg／kg；添加复合硅胶可吸附沉淀部分蛋白质颗粒，降低啤酒色度，提高啤酒非生物稳定性。     

生产工艺对高辅料啤酒非生物稳定性的影响

探索了糖化方法、糖化温度、麦汁煮沸时间、麦汁pH值和PVPP添加量等生产工艺对高辅料啤酒非生物稳定性的影响.结果表明:最佳的糖化工艺条件是:采用一次煮出糖化法,糖化温度70℃,麦汁pH值为5.2～5.4,麦汁煮沸90min～100min.在啤酒中添加150mg/L的PVPP,可以明显降低啤酒中的多酚物质,提高高辅料啤酒的非生物稳定性.     

啤酒老化评价及酵母和发酵条件对啤酒抗老化影响的研究

本文研究了老化过程中啤酒的老化物质、TBA值、抗老化指标及其相互之间的关联性。相关性分析表明,TBA值与自由基清除活性（DPPH）、自由基阳离子清除活性（ABTS）及糠醛、Strecker醛存在显著的相关性,采用TBA评价啤酒老化程度是简单和可靠的方法。研究酵母和发酵条件对啤酒抗老化能力的影响,试验结果表明使用低代酵母、高活性的酵母、酵母接种量（0．8～1．6）×10^7／mL、在相对较高的发酵温度15℃条件下发酵,延长发酵冷贮存期,可降低发酵液TBA值;调节麦汁pH值5．2—5．4和适宜的麦汁溶解氧,有利于降低发酵液羰基化合物含量,提高啤酒抗老化能力。     

The Impact of Low Heat Load and Activated Carbon Treatment of Second Wort on Beer Taste and Flavour Stability

There is a vast repository of knowledge regarding improving beer taste stability via wort boiling. However, as far as we are aware, there are few reports dealing with taste stability improvement in terms of quality characteristics by boiling, under proper conditions, the first wort and second worts separately. In this study, more than 50 brews in a pilot scale brewing facility were conducted to investigate suitable boiling conditions for first and second worts. When the second wort (i.e., the last 10% of the total filtered wort) was kept under a low heat load atmosphere (78°C), casted to the boiling first wort, and then re‐boiled for 10 min, the produced beer exhibited no significant differences compared to that of the general beer in terms of taste stability. However, when an adsorbent (bentonite, silica gel, activated carbon or PVPP) was individually added to the second wort and the same boiling procedure was performed, the oxidized flavour of the forced aged beer, treated with activated carbon, significantly decreased, compared to that of the general brew (level of significance α = 0.01). The data from the chemical analysis and fermentation behavior are presented.     

模糊数学结合响应面法优化啤酒鱼的煮制工艺

为实现广西阳朔地方特色菜啤酒鱼的标准化加工,对啤酒鱼加工过程中煮制工艺参数进行优化。以罗非鱼为原料,通过模糊数学感官综合评价法,对啤酒鱼嫩度、弹性、组织状态、气味、滋味进行感官的权重分析;利用Box-Behnken响应面优化设计研究啤酒添加量、煮制时间、加热功率对啤酒鱼感官评分的影响;分别使用气相色谱-离子迁移谱（gas chromatography-ion mobility spectrum, GC-IMS）和质构仪对用最优参数煮制的啤酒鱼进行挥发性风味物质测定及质构剖面分析（texture profile analysis, TPA）。结果表明:嫩度和滋味是影响啤酒鱼模糊数学感官综合评价值的重要指标,工艺参数对啤酒鱼综合评价值的影响强弱顺序为煮制时间>啤酒添加量>加热功率。啤酒鱼最佳煮制工艺参数为:啤酒添加量66%,煮制时间33 min,加热功率500 W,预测值7.89,实际综合评价值为7.91。啤酒鱼的啤酒风味主要由乙醇、2, 3-戊二酮等醇、酮类物质组成;啤酒的添加使鱼肉的硬度、咀嚼性降低。本研究可为啤酒鱼的工业化生产工艺提供一定的理论支持。     

The Role of Malt and Hop Polyphenols in Beer Quality,Flavour and Haze Stability

Pilot‐scale brewing trials of a 12°P pale lager beer were conducted to look at the effect of a modified dose of hop and malt polyphenols on haze, flavour quality, and stability. Results confirmed that malt polyphenols, and particularly hop polyphenols, in the course of wort boiling, improved reducing activity values and the carbonyl content in fresh and stored beers. Hop polyphenols significantly increased reducing activity and decreased the formation of carbonyls (TBA value) in fresh and stored beer. Reduced content of malt polyphenols, combined with the use of hop CO₂ extract, caused an increase in the TBA value in beer. PVPP stabilized beers tended to be lower in reducing activity. Both malt and hop polyphenols affected the intensity of “harsh taste” in fresh beers and a significant influence from PVPP stabilization of beer was not observed. The staling degree of forced‐aged beers depended on the polyphenol content in the brewhouse. Both hop and malt polyphenols had a positive impact on flavour stability. PVPP treatment of beer had a positive effect on the flavour stability of heat‐aged beers. Polyphenols, especially hop polyphenols, slowed down flavour deterioration during the nine month storage period, but the primary effect was seen during the first four months of storage. Storage trials did not show any unambiguous effects for PVPP stabilization on beer flavour stability. Results confirmed the negative impact of malt and hop polyphenols on haze stability, and PVPP stabilization minimized differences in shelf life prediction values between beers prepared with the modified dose of polyphenols.     

降低啤酒中乙酸含量的初步研究

啤酒中的乙酸主要来自麦芽及发酵过程。不同品种和制麦工艺制作的原料麦芽中乙酸含量有较大差异。麦汁浓度与麦汁pH值的升高均使乙酸增加，尤以后者的影响更显著。发酵前期，乙酸含量不断减少，在后酵过程中到达最低值后缓慢上升，最后趋于稳定。另外，在保证煮沸麦汁质量的前提下，增加煮沸时间和强度能大量减少乙酸含量。空气洗涤处理对麦汁中乙酸量的降低也有明显影响。     

新型添加剂Brewbrite在麦汁制造中的应用

对Brewbrite在麦汁中的应用进行了初步研究．通过麦汁外观和其他指标的分析。结果表明，在麦汁煮沸结束前10min添加Brewbrite 30mg／L，可以有效地澄清麦汁，降低麦汁中的可凝固性氮含量。与卡拉胶、单宁、HD-003，DHG，PVPP等添加剂相比，Brewbrite可降低麦汁和啤酒中的总多酚含量、可凝固性氮含量、麦汁色度、麦汁浊度等，减少高分子氮的比例，有助于提高啤酒的非生物稳定性。（孙悟）     

一种增香黑啤酒的研制

通过在麦汁煮沸时添加中草药，研制出一种具有独特芳香气味的黑啤酒，此黑啤酒为红棕色，口味协调，香气怡人。详细介绍了中草药的种类、添加比例和添加量及此黑啤酒的生产工艺。     

异构酒花颗粒在啤酒酿造中的应用研究

对异构酒花颗粒和普通酒花颗粒进行了对比研究。结果表明,添加异构酒花颗粒可减少苦味物质的损失,酿造出的啤酒优于只采用普通酒花颗粒酿造出的啤酒,特别是酒花香突出,泡特性好。     

A study of beer bitterness loss during the various stages of the Romanian beer production process

Beer is one of the oldest known alcoholic beverages produced by a yeast fermentation of a cereal extract that was germinated in water beforehand. The bitter taste of beer comes from the group of substances introduced during wort boiling, which are the extracted components of hops. The aim of this study was to determine some characteristics of beer (original extract, alcohol content, colour, pH, total acidity, carbon dioxide and bitterness values) during the three stages of the beer production process in a typical Romanian brewery. Measurements were carried out on 60 samples of beers, 10 measurements for each step of the process examining wort, unfiltered fermented beer and bottled beer (final product) from two different types of beer (light and dark). Statistical process control of the beer was performed. Losses in the bitterness units during the production process were between 24.7 and 41.54%, reported in terms of final product. Copyright © 2013 The Institute of Brewing & Distilling