葡萄酒和果酒下胶澄清和稳定工艺的再探讨

最近经常接到一些酿酒师来电咨询葡萄酒下胶澄清和稳定的相关技术问题,基于职业的特点和对葡萄酒的钟爱,在共同探讨和学习的过程中,在公司酿酒技术服务工程师和国外专家的指导下,终于促成了本文的完成.我们也希望该文能对促进国内葡萄酒和果酒界的技术交流和进步起到抛砖引玉的作用,同时作为专业的葡萄酒和果酒技术辅料提供商,也希望在提升中国葡萄酒和果酒的整体质量水平的事业中做出自己应有的贡献.     

两种澄清剂对4种鲜葡萄酒的下胶效果分析

选用保香皂土和蛋清作为下胶澄清剂对4种鲜葡萄酒下胶,分析2种下胶澄清剂的下胶量对4种鲜葡萄酒热稳定性及感官质量（包括外观、香气和口感）的影响。结果表明,鲜酒轻柔桃红葡萄酒、鲜酒轻柔红葡萄酒和鲜酒浓甜红葡萄酒选用保香皂土下胶,下胶量为1.0 g/L时,3款葡萄酒的热稳定性均合格且风味物质损失最少,感官评分分别为92、91、93;鲜酒轻柔干红葡萄酒选用蛋清下胶,下胶用量为0.07 g/L时,轻柔干红葡萄酒热稳定性合格且风味物质损失最少,感官评分为93分。     

不同澄清方法对山葡萄酒澄清效果的影响

采用不同的澄清方法对山葡萄酒的澄清效果进行了对比试验。结果表明,采用不同的澄清方法可获得不同的效果,澄清后的葡萄酒透明度提高,色泽更加鲜艳。     

葡萄酒澄清工艺探讨

作者根据皂土膨胀时表面急剧增大，可提高吸附效率的原理，提出了以分次添加皂土代替传统加胶的方法，改造了葡萄酒的澄清生产工艺。通过多次生产性实验，证明方法可行，提高了葡萄酒的稳定性。并具有易于操作、安全、效果好的特点。     

不同澄清剂对葡萄酒澄清效果及葡萄酒品质的影响

本试验从澄清后葡萄酒的澄清效果及下胶处理后酒样的部分理化指标等方面比较研究了明胶和皂土（或明胶和皂土配合使用）、蛋清粉、明胶＋蛋清蛋白、植源胶、蛋清蛋白对葡萄酒的澄清效果,确定了不同澄清剂的最佳使用剂量。结果表明,明胶＋蛋清蛋白、植源胶在起到澄清作用的同时,葡萄酒综合理化指标及感官质量明显优于其它几种澄清剂法,最佳澄清剂量为明胶＋蛋清蛋白90mg／L,植源胶80mg／L。     

不同澄清剂对葡萄酒澄清效果及葡萄酒品质的影响

本试验从澄清后葡萄酒的澄清效果及下胶处理后酒样的部分理化指标等方面比较研究了明胶和皂土(或明胶和皂土配合使用)、蛋清粉,明胶+蛋清蛋白、植源胶、蛋清蛋白对葡萄酒的澄清效果,确定了不同澄清剂的最佳使用剂量.结果表明,明胶+蛋清蛋白、植源胶在起到澄清作用的同时,葡萄酒综合理化指标及感官质量明显优于其它几种澄清剂法,最佳澄清剂量为明胶+蛋清蛋白90mg/L,植源胶80mg/L.     

葡萄酒下胶时应注意的几个问题

葡萄酒下胶是指通过加入能促使发酵结束后的原酒中的悬浮物及有害微生物沉淀的有机或无机物质,从而使酒变得澄清和稳定的操作,它是每一个葡萄酒生产厂家的工艺流程中都必须进行的一道非常普通而又十分重要的工序。但在生产实际应用中,由于设备不完善或操作不当,往往不...     

葡萄酒澄清和稳定工艺理论与实践探讨

1澄清工艺概述葡萄酒的澄清是指通过特定工艺手段使酒中的悬浮物沉降下来的过程。由于胶体的作用,未经澄清处理的新葡萄酒往往浑浊、透明度差,为了保证葡萄酒质量,使其成为澄清透亮的合格产品,必须进行及时澄清处理,目前主要有以下几种澄清法:(1)自然澄清法:通过自然     

如何对葡萄酒进行下胶

葡萄酒营养丰富、成分复杂,其中一些成分以真溶液状态存在,而另外一些成分以胶体状态存在,这些胶体物质与葡萄酒的感官质量密切相关,葡萄酒浑浊沉淀现象多是由这些胶体物质引起的.为了保证葡萄酒装瓶后能够澄清、稳定,几乎所有的葡萄酒在装瓶前都至少经过一次下胶.所谓下胶,就是在葡萄酒中加入亲水胶体,使之与葡萄酒中的胶体物质发生絮凝反应,将这些物质除去.但是下胶会对葡萄酒产生一些负面影响,例如,口味变淡,红葡萄酒颜色变浅等.所以,如何合理地进行下胶,将下胶的负面影响降低到最低程度,就成为酿酒工作者的心愿.     

不同澄清剂对起泡葡萄酒原酒的澄清作用及对香气品质的影响

以自然澄清的起泡葡萄酒原酒（霞多丽）为试材,研究大豆蛋白、皂土、酪蛋白、明胶和聚乙烯吡咯烷酮5?种不同类型下胶澄清剂对酒样澄清度、理化指标、风味成分和感官品质的影响。结果表明,下胶澄清处理可显著提高酒样透光率、降低酒样色度（P＜0.05）,酒样中乙醇体积分数无显著变化,总酸、挥发酸、总糖和总酚质量浓度分别降低0.18～0.30、0～0.09、0.25～1.20?g/L和0.05～0.21?g/L,其中除皂土和酪蛋白对总糖含量影响较大外,各处理间总酸、挥发酸和总酚含量无较大差异;下胶澄清后酒样中香气物质的种类及含量均有所下降,但大豆蛋白处理组中香气化合物含量显著高于其他处理组,主成分分析也印证了这一结果;200?mg/L大豆蛋白处理的酒样澄清透亮,香气浓郁丰富,感官评价最接近自然澄清的对照组,表明新型植物蛋白澄清剂大豆蛋白可用于起泡葡萄酒原酒的下胶澄清。     

如何料学地把握葡萄酒的"下胶"和"澄清"工艺--就部分洒厂的该项工艺进行商榷

最近带着国外酿酒专家走访客户时我们发现,部分酒厂无论对白葡萄酒还是红葡萄酒,均全部或大量采用皂土下胶--这使得国外专家非常震惊!于是国外专家和这部分酒厂的酿酒师进行讨论,这些值得大家思考.     

Effects of fining agents on trans-resveratrol concentration in wine

Resveratrol has been identified as a wine component related to moderate wine consumption and a reduction in serum cholesterol levels. Processes such as wine fining that result in loss of resveratrol during winemaking are therefore of interest, and led to these present studies. A number of agents were compared and were found to lower resveratrol levels in all wines to some extent. Results from two studies (1996 and 1997) are reported. The standard addition method was used in combination with High Pressure Liquid Chromatography to calculate resveratrol levels. In Study 1 (1996), recommended maximum levels of all fining agents (Level 3), bentonite, egg white, gelatin + kieselsol and polyvinylpolypyrrolidone (PVPP), lowered resveratrol levels significantly compared to controls (Level 0). Nevertheless, addition of fining agents at Level 0 resulted in resveratrol levels that were significantly higher than those at Level 3, but resveratrol levels in wine from Level 0 were not significantly different from Level 1. In Study 2 (1997), carbon + egg white, and gelatin + kieselsol fining was studied, and their effects differed according to grape variety. Least removal of resveratrol by carbon fining occurred in wine from Cabernet Sauvignon (Vitis vinifera) whereas most removal occurred in wines from Cynthiana (Vitis aestivalis) and Noble (Vitis rotundifolia). Resveratrol levels of control wine were significantly higher than resveratrol levels of wine treated with recommended maximum addition of fining agent in all varieties. Taken overall, any addition of any fining agent lowered resveratrol levels in all wines to some extent, but complex interactions between fining agent and wine variety resulted in different regression trends. While recognising the constraints set by our particular data that could reflect unique circumstances, we are nevertheless able to infer from these trends that low levels of fining agents can be used without statistically significant loss of resveratrol.     

Clarifying effect of different fining agents on mulberry wine

Fining experiments have been conducted on mulberry wine, in which five fining agents (bentonite, gelatin, casein, egg albumin and PVPP) were investigated. The effect of these agents on polyphenol content, colour intensity, antioxidant activity and aromatic profile has been determined. In general, all treatments improved the limpidity of the mulberry wines to some extent. The wine was mostly negatively affected by gelatin and led to the greatest reduction of phenol content (16.61%), colour intensity (32.26%) and antioxidant activity. Concerning aroma, the addition of PVPP, casein and bentonite both significantly altered the aroma profile. It is noteworthy that egg albumin led to the lowest diminution total phenol value (5.74%) and improvement of antioxidant capacity and colour among the tested fining agents. Furthermore, the aroma profile remained mostly unaffected by egg albumin. As consequence, the optimal fining agent for mulberry wine was egg albumin.     

澄清剂对黄酒混浊蛋白去除效果的研究

研究了单宁、硅胶和Polyclar R Brewbrite等澄清剂对黄酒混浊蛋白特异性去除的效果,并通过采用N-三(羟甲基)甘氨酸-十二烷基磺酸钠-聚丙烯酰胺凝胶电泳、基质辅助激光解析电离飞行时间串联质谱,研究了黄酒混浊蛋白及不同澄清剂吸附蛋白的分子量、蛋白质种类及来源,并比较了澄清剂处理前后酒样隆丁区分和非生物稳定性的变化。结果表明:黄酒混浊蛋白的主要成分为类燕麦蛋白和二聚α-淀粉酶抑制剂,主要来源于小麦,几种澄清剂对二聚α-淀粉酶抑制剂都有一定的吸附作用,且处理后的酒样稳定性得到提高,其中以单宁效果最为明显。     

Amelioration of smoke taint in wine by treatment with commercial fining agents

Background and Aims: Fermentation of smoke‐affected grapes can lead to wines that exhibit objectionable smoke‐related sensory attributes, i.e. smoke taint. Fining agents are routinely used at different stages of the winemaking process to address constituents that are considered to adversely affect juice or wine quality. This study aimed to evaluate the efficacy of commercial fining agents in reducing the concentration of volatile phenols and the intensity of sensory attributes associated with smoke‐tainted wine. Methods and Results: Smoke‐affected wines were treated with a range of fining agents, two of which, an activated carbon and a synthetic mineral, were found to appreciably ameliorate the taint. Treated wines contained a significantly lower level of smoke‐derived volatile phenols and exhibited less intense ‘smoke’ and ‘cold ash’ aromas, ‘smoky’ flavour and ‘ashy’ aftertaste, compared with that of untreated (control) wines; with little or no impact on wine colour. Conclusions: Selected fining agents can ameliorate smoke taint in wine. Whereas most fining agents showed poor specificity towards the wine components responsible for smoke taint, some, an activated carbon in particular, were highly effective. Significance of the Study: This research identifies a treatment that can be used to mitigate the impact of grapevine exposure to smoke on wine composition and sensory properties.     

Impact of wine manufacturing practice on the occurrence of fining agents with allergenic potential

Proteinogenic wine fining agents are hidden allergens and could present a risk for consumers with allergies. Therefore, the European Parliament adopted Directive 2003/89/EC amending Directive 2000/13/EC to declare ingredients, contaminations and processing aids that are known to trigger allergic reactions. The Amendment Regulation (EU) 1266/2010 excluded the labelling of wines which are processed with hen’s egg and products thereof until 30 June 2012 to get more scientific findings. After 1 July 2012 wine fining agents have to be declared if above 0.25 mg l^–1 (Regulation (EU) 579/2012 in conjunction with article 120 g of Regulation (EU) 1234/2007). The Organisation International de la Vigne et du Vin (OIV) advises this limit of detection (LOD) for potential allergenic residues of proteins. Wine fining agents are processing aids and according to the wine producer’s knowledge will be removed after coagulation by filtration or other production steps. Due to lack of scientific data, residues of fining agents in the final product could not be excluded. In this risk assessment, highly sensitive ELISA methods for ovalbumin of known origin for wine have been developed. The objective was to investigate the presence of allergen residues in wine after certain technological treatments were applied to remove the wine fining agents. For all developed ELISA methods the LODs are in the low µg l^–1 range between 5 and 10 µg l^–1 fining agent, whereas the LOQ varies between 5 and 80 µg l^–1 fining agent. The results of the investigation of well-known wines and fining agents demonstrate that white wines fined with white or ovalbumin from hen’s egg could retain allergens. The use of certain technological procedures during wine processing leads to different results. In white wine, bentonite or sheet filtration followed by sterile filtration lead to wines containing no detectable amounts of ovalbumin. In red wine, especially the final sterile filtration removes the fining agents.     

Interactions between protein fining agents and proanthocyanidins in white wine

A comparative fining trial was conducted in a laboratory scale to study the influence of protein fining agents on proanthocyanidins, colour and browning potential of white wine. The monomeric flavanols were significantly depleted by casein, and gelatine with low molecular weight (MW) distribution, and isinglass obtained from fish swim bladder (MW > 94.0, containing some bands in the range 94.0–43.0 and at 20.1 kDa). However, the other gelatines and isinglass with a MW polydispersion below 20.1 kDa did not interact significantly (P < 0.05) with these compounds. In contrast, the oligomeric compounds were not decreased by swim bladder isinglass. It was also observed that neither of the isinglasses decreased the polymeric flavanols significantly (P < 0.05). Although casein and potassium caseinate had similar MW distributions and isoelectric points, potassium caseinate decreased the polymeric flavanols, whereas casein did decrease monomeric, oligomeric and polymeric flavanols significantly (P < 0.05). The degree of polymerisation of polymeric proanthocyanidins that remained in the fined wine decreased significantly (P < 0.05) after addition of protein fining agents except when potassium caseinate was used. Casein, potassium caseinate and swim bladder isinglass induced a significant (P < 0.05) decrease in wine colour (A_420nm), a decrease in browning potential and a decrease in turbidity.     

Comparing the impact of bentonite addition for both must clarification and wine fining on the chemical profile of wine from Chambave Muscat grapes

The impact of bentonite fining is generally studied on final wines, and few studies have evaluated it throughout the winemaking process. This work studied the fate of proteins and terpenols, the main targets of bentonite addition, during the processing of Chambave Muscat aromatic grapes. The experimental trials were performed in two vintages (2006 and 2007) and included the following processes: bentonite addition to must only (100 g hL^?1 in both vintages), fining of wine only (100 g hL^?1 in both vintages), double bentonite treatment on must and wine (200 and 150 g hL^?1 in 2006 and in 2007, respectively) and no treatment (control). The results demonstrated that the treatment allowing the best removal of protein was the addition of bentonite to must only. Moreover, a lower removal of free terpenols was observed in samples from double treatment compared with wines fined with bentonite only after alcoholic fermentation.