糖化工艺对麦汁糖组分的影响

本文探讨在麦汁制备过程中，不同的糖化工艺对麦汁糖类成分的影响。在生产中，必须针对实际情况，制定合理的糖化配方，以得到适合的麦汁糖组分。     

用麦芽四糖淀粉酶生产麦芽四糖

采用麦芽四糖淀粉酶，以可溶性淀粉为底物进行了包括温度、ｐＨ值、反应时间、加酶量等多种产糖条件的试验，得到了较理想的反应参数。所得产品麦芽四糖占总糖的比例达８０％以上，转化率为５５％左右。     

重组Bacillus subtilis产麦芽四糖淀粉酶的发酵优化及麦芽四糖制备

麦芽四糖淀粉酶可水解淀粉或麦芽糊精生成麦芽四糖,在食品领域有着广泛应用。为降低生产成本,对前期构建的生产麦芽四糖淀粉酶的重组枯草芽孢杆菌进行发酵优化。通过对培养基的氮源和碳源进行优化,以5%的接种量,在33℃、200 r/min条件下发酵48 h,发现以25 g/L豆粕粉和25 g/L工业蛋白胨为氮源,5 g/L甘油为碳源时,重组酶酶活力最高可达236 U/m L。利用发酵所得重组麦芽四糖淀粉酶制备麦芽四糖并进行酶反应条件优化,使用高效液相色谱检测产物含量。发现当酶转化反应温度为50℃,反应p H为7. 0,加酶量为30U/g底物,底物麦芽糊精的质量浓度为250 g/L时,反应12 h,麦芽四糖转化率可达73. 2%,为降低生产成本和工业制备麦芽四糖提供了理论依据。     

生长调节剂对麦芽中淀粉酶活力的影响

对大麦发芽过程中生长调节剂影响麦芽合成淀粉酶的活性进行了研究,结果表明:大麦发芽过程添加适量的生长调节剂可以明显提高淀粉酶活性.     

几种α-淀粉酶系生产麦芽低聚糖工艺研究

用三种α－ 淀粉酶系与普鲁兰酶协同糖化、精制、工业化生产出三种麦芽低聚糖浆。在现有酶源条件下,为生产麦芽低聚糖找到了捷径。     

Thermobifida fusca麦芽三糖淀粉酶的重组表达及其在麦芽三糖制备中的应用

麦芽三糖淀粉酶以淀粉或麦芽糊精为原料,可生产麦芽三糖,在食品、饮料等行业具有广泛的应用前景。实验将Thermobifida fusca NTU22来源的麦芽三糖淀粉酶在枯草芽孢杆菌WS11中进行重组表达,并进行酶学性质分析,重组酶的最适温度和pH分别是55℃和6.0。在此基础上探究了重组酶作用于麦芽糊精生产麦芽三糖的最佳条件。结果表明,以15%浓度的麦芽糊精(DE 5-7)作为底物时,酶转化的最佳条件是温度55℃、pH 5.5、加酶量60 U/g(底物)、普鲁兰酶加酶量32 U/g(底物)、反应时间11 h,此时得到麦芽三糖转化率44.4%。该研究为工业制备麦芽三糖提供了理论依据。     

麦汁组分对酵母凝聚性的影响

多年以来，我公司啤酒生产使用的麦芽一直以进口大麦加工的澳麦芽为主，麦芽质量很稳定，没有出现过质量问题。但去年7月份以来出现了啤酒后酵过程酵母不易沉降的现象，滤酒前酵母数在800—1000万个，毫升，个别罐次达2000万个／毫升，严重影响啤酒过滤，造成硅藻土耗量增加，酒损上升。针对这一问题进行了系统的检查分析。     

几种α—淀粉酶系生产麦芽低聚糖工艺研究

用三种α－淀粉酶系与普鲁兰酶协同糖化，精制，工业化生产出三种麦芽低聚糖浆，在现有酶源条件下，为生产麦芽低聚糖找到了捷径。     

糖化中麦芽淀粉酶系热稳定性的研究

本文研究了糖化过程中麦芽淀粉酶系的热稳定性、不同品种麦芽间淀粉酶热稳定性的差异及对麦汁糖组分的影响。结果表明糖化中45～65℃α-淀粉酶活力变化不显著;β-淀粉酶在60℃左右时酶活最大;极限糊精酶在45～60℃时酶活力稳定;温度超过60℃,β-淀粉酶和极限糊精酶的酶活显著下降,温度超过65℃α-淀粉酶活力下降明显。不同品种麦芽中淀粉酶系的热稳定性存在差异,其中β-淀粉酶热稳定性的差异最为显著。麦芽品种对麦汁可发酵性的影响明显。研究表明β-淀粉酶活力及其热稳定性是决定麦汁可发酵性的主要因素。     

麦芽四糖的性质及在食品中的应用

报道了新型麦芽低聚糖－－麦芽四糖的理化性质、保健功能其在食品中的应用,介绍了20世纪80年代以来国际、国内在麦芽四糖方面的研究进展。     

α-液化酶在麦汁制备中的应用

随着啤酒产业的技术革新与发展,传统的、原始的工艺正逐步的被快捷先进良好的工艺所取代,同时也使啤酒的更新换代步伐加快。这给整体啤酒业带来了一次技术性的飞跃,又为啤酒内在产品质量的稳定提高打下了坚实的基础。酶制剂在啤酒生产中的广泛使用,对一些由于资金不足、麦汁制备中使用的麦芽质量较差的厂家来说,是一次质的飞     

啤酒大麦制麦过程中淀粉酶活性变化动态的研究

以不同品种的大麦为材料,运用底物分析法检测3种淀粉酶的活性。不同品种的大麦中α-淀粉酶、β-淀粉酶和极限糊精酶活力差异较大,因此实际生产中可对不同品种大麦进行筛选,选用酶活较高的大麦来制备麦芽;在制麦过程中,浸麦可在一定程度卜抑制淀粉酶的活力;淀粉酶的总活力在发芽初期缓慢增加,2d～3d后急剧增加至最大值;焙焦可使3种酶酶活有不同程度地下降。     

麦汁过滤性能与麦芽质量相关因子的研究

麦芽质量是影响麦汁过滤性能的重要因素,该研究采用小型模拟过滤设备,控制恒温恒压,对不同质量麦芽进行粉碎、糖化、过滤,评价一系列麦汁过滤性能参数及主要影响指标,麦汁过滤性能评价参数包括200m L过滤时间、总过滤量、滤饼重量、20 s过滤性能和总过滤性能,麦芽溶解度和黏度是麦汁总过滤性能的主要影响指标。同时采用贝克曼库尔特LS 13 320型激光衍射粒度分析仪、贝克曼Multisizer 3库尔特计数及颗粒分析仪两种设备对过滤前后的麦汁进行粒度分析,确定了麦汁过滤前、过滤后的粒径分布及粒径分布与麦汁过滤性能的关系。     

国产苏北麦芽麦汁浊度的影响因素研究

研究了多酚、糊精、蛋白类物质对苏北麦汁浊度的影响。结果表明,苏北麦汁浊度受各添加物的影响程度排序为高、中分子蛋白多酚糊精,麦芽糊精对苏北麦汁浊度无明显影响。故酿造时应重点控制高、中分子蛋白和多酚的含量。     

一种麦芽β-淀粉酶的纯化和特性研究

主要对一种麦芽中提取的β-淀粉酶进行特性的研究。纯 化研究发现,采用乙醇分级和Sephadex G—75相结合的 方法,可使酶的比活从389U/mg提高到1410U/mg,纯化 后酶的性质与原粗酶基本相似:最适温度都是50℃,最适 pH分别是5.8、5.6;高效液相色谱对粗酶水解产物分析, 水解产物里主要是麦芽糖,仅有少量的葡萄糖和少量麦 芽四糖或五糖,说明该麦芽β-淀粉酶酶系较纯。     

The influence of malt and wort processing on spirit character: the lost styles of Scotch malt whisky

Over the last 50 years there has been considerable analytical research on the malt parameters which govern the flavour and aroma, i.e. the ‘character’, of Scotch malt whisky. This has led to a standard format, the Flavour Wheel, to describe the attributes of any malt spirit and to relate them to a common group of malt parameters. What has not been well documented in the same period are the changes in malt processing technology which have led to a gradual but significant change in the concentrations of reference compounds used in the Flavour Wheel relating to sulphury, nutty/burnt/smoky, peaty and fruity/estery characters. This review covers the most significant of these changes, which have become common practice across the industry, and specifically demonstrates how different malting barley varieties, malt kilning and peating, wort recovery, yeast management, and wash still heating have all contributed to the loss of some styles of malt whisky. © 2019 The Institute of Brewing & Distilling     

Impact of Fusarium infection and fungicide treatment on wheat malt wort quality

Two wheat genotypes varying in susceptibility to infection by Fusarium species were assessed by four different treatments in the field: (a) control, (b) treated with fungicide (Prosaro®), (c) inoculated with Fusarium culmorum spores and treated with fungicide and (d) inoculated with F. culmorum spores. Wort quality indicators (saccharification time, speed of filtration, wort colour, pH, extract, air dried extract and dried extract) were determined using standard methods. The results indicate that infection with F. culmorum affected wort quality, particularly wort colour and significantly extended (or stopped) saccharification and rate of filtration. Treatment with fungicide reduced the extent of quality deterioration, even with samples infected with F. culmorum. The wheat type which was less susceptible to Fusarium infection produced less compromised worts, confirming its superiority to the more susceptible wheat genotype. Further study is suggested at a commercial scale to determine the interrelationship between Fusarium infection, fungicide treatment and wheat malt quality. © 2018 The Institute of Brewing & Distilling     

Effects of arabinoxylan solubilization on wort viscosity and filtration when mashing with grist containing wheat and wheat malt

Arabinoxylans are partially water-extractable, high-molecular-weight polymers that contribute to the problems of viscosity and membrane filterability during beer brewing. These problems are more pronounced when wheat and wheat malt are used as adjuncts due to their higher arabinoxylan contents and higher molecular weights. This paper aimed at investigating the effects of mashing temperature, time, grist size and liquor:grist ratio on the solubilization of arabinoxylans. Results indicated that increasing the mashing temperature generally increased the amount of arabinoxylans released into the wort. When greater proportions of wheat or wheat malt were used as adjunct, higher arabinoxylan contents in the final wort were observed. The more finely ground the grist, the more were arabinoxylans released into the wort. When more diluted mashes were used, more efficient solubilization of arabinoxylans was observed. The effects of arabinoxylan content and β-glucan content on the wort viscosity were also examined using a General Linear Model (GLM). There was a good correlation (R² = 0.98) between wort viscosity and its arabinoxylan and β-glucan contents.