浓香型高低度白酒货架期稳定性对比研究

试验主要通过对浓香型高低度白酒在货架期中总酸、总酯、己酸乙酯及酸酯比值等变化的对比研究,发现低度成品酒虽然在储存过程中各理化成分相较于中高度成品酒变化速度稍快,但是对比同样低度的原酒变化相对缓慢。要想让低度成品酒在货架期间能够更稳定,不仅要选用好的基酒和调味酒,还要让酒体更加协调,尽量使勾兑好的酒总酸含量高些以抑制己酸乙酯的水解。增加酸的用量,扩大酸酯比,在对口感质量影响不大的前提下,使酸和酯尽可能地接近平衡,从而减少由于酸与酯不平衡导致的酒体在货架期内口感质量发生变化的现象产生。     

关于低度浓香型白酒几个问题的探讨

对低度浓香型白酒的研究发现,基础酒的质量、除浊工艺、勾调技术是影响其质量的重要因素;低度浓香型白酒在货架期易水解,增加酒的水味和酸味.采用活性炭吸附法与优质调味酒调味可有效解决低度酒失光、浑浊与酒体寡淡问题;用高酸、高酯白酒及含有丰富微量成分的基酒可提高低度浓香型白酒的稳定性,延长货架期.(孙悟)     

低档低度浓香型白酒稳定性研究

适当提高酒中总酸含量可以改善低度白酒质量。在低度白酒中添加不同含量的酸后,选取口感较好的酒样观察其在货架期内的稳定性。结果表明,酒体中添加适量的酸后,能提高酒体质量且能增加其货架期稳定性,添加适量的己酸可使酒体的稳定性达到最好。     

低度白酒生产方式的研究进展

高度白酒加浆降度后,会产生沉淀物质,且口感改变较大.要使低度白酒延续高度酒的风味,首先须生产出酸酯比例协调的基础酒,精心勾调之后,再通过吸附法、过滤法、复蒸馏法、加入增溶剂等方法除去沉淀物质,观察其在货架期内酸、酯含量的变化.回顾了低度白酒在生产、勾调、除浊澄清及货架期稳定性的进展,展望了超低度白酒的未来.     

不同香型的低度白酒在货架期的质量变化

通过研究酱香型、浓香型、兼香型3种香型高、低档低度白酒在货架期的质量变化,围绕酒精度、总酸、总酯、主要色谱成分在货架期的变化,探究不同货架期对不同香型高、低档低度白酒的质量影响。结果发现,在水解反应的作用下,3种香型的低度白酒的酒精度都有不同程度的降低,总酸、总酯呈"酸增酯减"的规律,并有着明显阶段性特征,在前期(第一年)"酸增酯减"表现明显,中期、后期,总酸、总酯趋于稳定,变化幅度较小。主要色谱成分中,四大酯主要呈下降趋势,乙醛、乙缩醛变化较小。感官质量方面,3种香型低度白酒的风格典型性始终存在,货架期对于3种香型低度白酒感官质量的提升主要为陈香、柔和度和风格典型性,且高档白酒的提升更为明显,而低档白酒的爽净度有所下降。     

浅谈低度白酒存储过程的变化

本文主要通过对不同档次低度白酒的货架期质量的变化情况,进行定期追踪检验、品评,发现其中的一些变化情况,以便进行酒体设计,确保产品质量。发现在存储过程中总酯逐步下降、总酸增加;低档酒的质量明显下降,高档酒质量较稳定。     

气相色谱在低度白酒分析中的应用

低度白酒随酒精度的降低,酒中微量的呈香呈味物质溶解度降低而析出,微量成分含量减少,彼此间的平衡、协调、缓冲等关系被破坏,同时在货架期发生氧化、水解等反应,使低度白酒、降度白酒易出现"味淡"、"欠丰满"、"单调"、"欠浓厚"等问题.利用气相色谱法进行酒体设计、基础酒成分分析、低度白酒和降度白酒货架期成分跟踪分析,了解低度白酒质量变化的原因,再进行香型融合,可生产高质量的低度白酒,提高低度白酒在贮存过程中的质量稳定性.     

有机酯在低酒精度水溶液中的贮存变化分析

低度白酒中有机酯在酒体中的变化一直是白酒行业中非常热门的话题，通过对有机酯在单纯低度酒精-水溶液的贮存变化和添加对应有机酸后的变化从而验证有机酯在低度酒精-水溶液中的变化规律属于有机酯的酸水解过程，对应酸在其中起催化剂的作用。     

冷冻过滤技术在特香型白酒中的应用

为了解决低度白酒在低温下容易出现失光、浑浊或沉淀等问题,提高特香型低度白酒的质量,四特酒公司引进了冷冻过滤设备,并研究了冷冻过滤技术在低度白酒生产中的应用效果和最佳工艺参数,为实际生产提供了真实可靠的数据支持。同时,通过冷冻过滤和活性炭吸附过滤的对比实验,证明了冷冻过滤技术能更有效地减小低度白酒中总酸、总酯和微量香味成分的损失,使酒体香气舒适、入口绵甜,从而提高了成品酒的质量。     

低度白酒生产技术的现状与创新

低度白酒在货架期易出现结晶形沉淀、白色絮状沉淀或失光现象,及发生水解、氧化与还原、缔合与离解、凝胶与溶胶等变化。可采用胶溶特性、助溶原理的应用和提高酒体的缔合度措施延缓中低度白酒质量变化。中国低度白酒应该从淡化香型概念、缩短发酵周期、降低有机酸酯的含量、全液法发酵生产等方面突破,进行生产工艺的创新、创新中国白酒。（孙悟）     

白酒中酸酯含量及平衡性在勾兑中的作用

酸酯平衡是白酒勾兑的核心，酸与酯相辅相成，相互依托。酸是形成白酒口味的主要香味物质，是形成酯类物质的前趋物质，必须注意酸的含量与配比。四大酸的结构和平衡性对酒质影响很大。酒的香主要由酯决定，四大酯的比例不同而形成了各具独特风格的众多香型的酒。勾兑中应注意四大酯的量比关系及含量(陶然)     

Equilibrium moisture content of bell pepper

Equilibrium moisture content (EMC) of bell pepper at selected levels of temperature (30‐70°C) and relative humidity (10‐75%) of the surrounding air was determined experimentally by the static method. The EMC increased with relative humidity but decreased with increase in temperature. Results demonstrated that Henderson model predicted accurately the variation of EMC with relative humidity at selected temperatures. The standard error was less than 0.077 while correlation coefficient was greater than 0.942 in all cases.     

Research Watch: Equilibrium composition

Assessment.     

谷物平衡水分研究概况

控制吸湿是谷物安全贮藏的基本原则之一,平衡水分测定可用来判断谷物水分变化的趋向.概述了谷物平衡水分测定的原理及数学模型分析,并归纳,发生纳滞后效应的可能理论、影响谷物吸着(包括吸附与解吸)等温线测定的因子,还重点介绍了近年发展起来的、利用平衡水分吸附/解吸数据分析谷物及食品的热动力学函数--水分吸着等热.这些研究进展对完善我国储粮生态区域划分、谷物主产区低温干燥、设计干燥程序和设备、谷物及加工产品的包装及货架期皆有意义.     

Equilibrium modified atmosphere packaging of wild strawberries

Wild strawberries (Fragaria vesca L.) are high‐added‐value fruits but their marketing is complex owing to their short postharvest life. In this work, equilibrium modified atmosphere packaging (EMAP) technology was used to maintain their quality and consequently to extend their life. Fresh strawberries were packaged with two continuous and three microperforated films (with different gas permeabilities) with the purpose of obtaining equilibrium atmospheres of diverse compositions. Weight loss, pH and acidity, solid content, colour, firmness, fungal decay and development of off‐flavours were selected to monitor fruit quality during 6 days at 10 °C. Among the five packages tested, microperforated films with one and three perforations provided adequate CO₂ and O₂ equilibrium concentrations in view of the evolution of chemical and physical quality parameters. These results were confirmed by sensory analysis. Copyright © 2007 Society of Chemical Industry     

Equilibrium moisture content of groundnut and chillies

Hygroscopic material, when it comes into contact with atmospheric air, desorps or absorps the moisture from the surroundings until it reaches equilibrium. In the present study, groundnut and chillies were dried in a controlled air supply (at a particular temperature and relative humidity). The equilibrium moisture content (e.m.c.) and relative humidity (r.h.) relationships were studied at different temperatures. Values of constants c and n of Henderson's equation were computed and desorption isotherms were drawn for groundnut components and chillies. It was observed that e.m.c. depends upon type of material, the temperature and r.h. of the air.     

Equilibrium and kinetics of bromine chloride hydrolysis

Aqueous-phase halogen reactions play an important role in tropospheric ozone depletion that is observed during Arctic sunrise where bromine chloride is a key intermediate. The temperature dependencies of BrCl(aq) equilibration with BrCl2-, HOBr(aq), Br2(aq), Cl2(aq), HOCl(aq), Br-, and other species (Br3-, Br2Cl-, Cl3-, OBr-, and OCI-) are determined as a function of Cl- concentration from pH 0 to pH 7. Values for K1 (=[BrCl2-]/([BrCl(aq)][Cl-])) at mu = 1.0 M are 3.8 M(-1) at 25.0 degrees C, 4.7 M(-1) at 10.0 degrees C, and 5.5 M(-1) at 0.0 degrees C, with deltaH1 degrees = -9.9 kJ mol(-1) and deltaS1 degrees = -22 J K(-1) mol(-1). BrCl(aq) hydrolysis equilibria have little or no temperature dependence with Kh1 (=[HOBr(aq)][Cl-][H+]/[BrCl(aq)]) = 1.3 x 10(-4) M2 from 25.0 to 5.0 degrees C, mu = 1.0 M. When conditions are adjusted to give a rapid partial hydrolysis of BrCl in equilibrium with HOBr and Cl- at p[H+] 4.31, a relatively slow reaction (kobsd = 2.4 s(-1)) to form HOCl and Br- is observed. This takes place via BrCl reaction with Cl- to form Cl2, which hydrolyzes in the rate-determining step to give HOCl. On the other hand, the rate of complete BrCl hydrolysis to form HOBr and Cl- at p[H+] 6.4 is extremely rapid with a first-order rate constant of 3.0 x 10(6) s(-1) at 25.0 degrees C. The reverse reaction between HOBr, Cl-, and H+ has a rate constant of 2.3 x 10(10) M(-2) s(-1), so that in seawater, where [Cl-]/[Br-] = 700, the formation of BrCl is much faster than the formation of Br2 from HOBr, Br-, and H+. Rapid formation of BrCl(aq) and its subsequent reaction with Br- is a viable pathway to give Br2(aq). Photolysis of Br2(g) is believed to initiate the reactions associated with ozone depletion.     

啤酒生产控制中的工艺平衡

通过对啤酒胶体稳定性、风味稳定性、泡沫、风味特点以及成本和质量之间的一些相互矛盾分析,提出在啤酒生产控制中应根据原料质量、成本目标、风味特点或消费者需求,品质及品质侧重需要等因素,采取工艺平衡的措施.