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高浓啤酒稀释技术在我国啤酒行业中,占据着比较重要的作用。良好的稀释技术,能帮助啤酒厂酿造更精纯的啤酒。本文对高浓稀释啤酒质量的内在与外在影响因素进行了分析说明,在此基础上提出了提高高浓稀释啤酒质量的有效措施,以期对提高啤酒厂高浓啤酒稀释技术与稀释啤酒的质量,具有一定的参考作用。 相似文献
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啤酒中含有一定量的SO2,SO2可由酵母产生,也可由外源添加的亚硫酸盐类物质产生。SO2对于保护啤酒的风味生物稳定性具有重要的作用,阐述了啤酒中SO2的来源、含量及在保护啤酒的风味生物稳定性等方面的作用。 相似文献
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Free radical reactions in beer during pasteurization 总被引:2,自引:0,他引:2
HIROTAKA KANEDA‡ YUKINOBU KANO TOSHIHIKO OSAWA† SHUNRO KAWAKISHI† SHOUHEI KOSHINO 《International Journal of Food Science & Technology》1994,29(2):195-200
Oxidative reactions during beer pasterization were studied using chemiluminescence (CL) and electron spin resonance (ESR) analyses. the CL production of beer was acclerated by pasteurization and the maximum CL intensity appeared sooner than that in non-pasteurized beer. Beers pasteurized with 15–30 pasteurization units (P.U) had the same CL producing activities as the non-pasteurized beers stored at 20°C for 6–10 days. Free radicals were produced and some of them were consumed by beer oxidation during pasteurization. It seems that free radicals were consumed by beer oxidation during pasteurization. It seems that free radical reactions occur in beer during pasteurization and that the degree of oxidation during pasteurization generally corresponded to that of non-pasteurized beer stored at room temperature for about 1 wee. 相似文献
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超氧化物歧化酶普遍存在于生物体内,具有清除氧活性自由基的生物活性,在啤酒生产过程中具有重要的作用.本文对啤酒风味老化因素给予了分析,并对减少啤酒风味的老化提供了一定的技术方案,重点对影响老化的关键因素氧进行了论述,并给与清除和阻断氧的方法,超氧化物歧化酶作为一种抗氧化剂,本文分别对麦芽、酵母中的超氧化物歧化酶的特性进行了分析,并且对啤酒发酵中不同时期提高超氧化物歧化酶的含量的措施给予了探讨,在生产过程中添加外源性超氧化物歧化酶对于提高原麦汁的还原力,发酵液的抗氧化力以及成品啤酒的风味稳定性都有明显的作用,同时,本文就目前外源性超氧化物歧化酶的来源,存在的问题进行了探讨,并对其在工业化生产上的应用前景进行了分析和探讨. 相似文献
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分别采用上面发酵工艺与下面发酵工艺进行100%大麦啤酒及100%麦芽啤酒的酿制,并对其麦汁的氨基酸含量、老化Strecker醛、自由基以及新鲜啤酒中老化Strecker醛的含量等进行了对比分析。研究发现,就麦汁而言,100%大麦麦汁中老化Strecker醛的含量都明显低于100%麦芽麦汁;同样的麦汁,上面发酵方式还原Strecker醛的能力明显优于下面发酵方式。就啤酒而言,经酵母还原后,新鲜啤酒中的老化Strecker醛含量较麦汁含量低,且100%大麦啤酒中老化Strecker醛的含量低于100%麦芽啤酒中的含量。100%麦芽麦汁的自由基含量是100%大麦麦汁的近3倍。这都预示着100%大麦啤酒的风味稳定性(新鲜度)明显好于100%麦芽啤酒。 相似文献
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选用啤酒酵母为原料,采用热水浸提提取还原型谷胱甘肽(GSH),经过高速离心分离、阳离子交换树脂纯化、等电点沉淀及真空浓缩干燥制备还原型谷胱甘肽。采用1,1-二苯基-2-苦肼基(DPPH)自由基反应体系,抗氧化性物质抗坏血酸作为参照物,根据DPPH·体系吸光值的变化研究GSH清除自由基的能力,DPPH·反应体系为5mL0.0817mmol/L DPPH·溶液+5mL样品溶液,反应时间30min。考察了不同浓度GSH和抗坏血酸与DPPH·自由基清除率的关系。结果表明,GSH比抗坏血酸抗氧化能力差一些,但GSH清除DPPH自由基能力与其浓度呈明显的量效关系,因此,啤酒酵母GSH有重要的抗氧化开发价值。 相似文献
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Dominik Szwajgier 《Journal of the Institute of Brewing》2009,115(3):243-252
Phenolic acids are widely distributed in foods and raw materials. They are easily absorbed by humans due to their simplicity. Once they enter the blood plasma, they act as antioxidants. Beer can be a rich source of phenolic acids in the diet. The aim of this study was to determine the concentrations of phenolic acids in two experimental worts and beers as well as in nine market beers (using HPLC‐UV). An examination of the total antiradical activities of phenolic acids with in vitro model systems (using ABTS and DPPH free radicals), at the concentrations comparable to those detected in beers, was performed. Only low fractions of the main phenolic acids present in barley malt (ferulic, vanillic and p‐coumaric acid) were detected in the experimental worts. Moreover, the concentrations of phenolic acids significantly decreased until the last steps of beer production. The main beer phenolic acids (vanillic and ferulic acid) exerted a lower share of total antiradical activity against both free radicals (calculated as the sum of the individual activities of all acids detected in beer) than the minor phenolic acids (caffeic, chlorogenic, o‐coumaric, sinapic or syringic acid). The synergies, between individual phenolic acids in pairs, were also studied with in vitro model solutions using free radicals. The total antiradical activity of the compounds studied in pairs, was at the most as high as the sum of the antiradical activity of the individual phenolic acids, but in most cases it was considerably lower (i.e. no synergy was detected). 相似文献
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C. Laane G. de Roo E. van den Ban M-W. Sjauw-En-Wa M.G. Duyvis W.A. Hagen W.J.H. van Berkel R. Hilhorst D.J.M. Schmedding D.J. Evans 《Journal of the Institute of Brewing》1999,105(6):392-397
The effect of riboflavin and riboflavin binding proteins on the light-induced formation of reactive oxygen species and sunstruck off-flavour was studied in model beer solutions. Under model beer conditions (pH 4.0, 1 ppm riboflavin, 5% ethanol and traces of O2) hydroxyl and hydroxyethyl radicals were formed upon illumination. Radical formation was measured with the spin traps N-t-butyl-α-phenylnitrone (PBN) and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). DMPO appeared to be a better spin trap than PBN for studying the effect of light exposure, since PBN is photochemically active by itself. Addition of isohumulones to the model beer reduced the amount of riboflavin-induced radicals. Two different riboflavin binding proteins were tested both for their ability to scavenge riboflavin and how in turn this influenced free radical formation. The apoform of egg white riboflavin binding protein (RfBP) was more efficient in reducing radical formation than an apo-flavodoxin protein isolated from Azotobacter vinelandii. Organoleptic assessment clearly indicated that the addition of apo-RfBP to model beer solutions, containing stiochiometric amounts of riboflavin as well as isohumulones and cysteine, reduced sunstruck off-flavour formation. The dual role of riboflavin and ethanol as radical propagators in oxidiatve flavour change is discussed. 相似文献