葡萄酒中为何含有二氧化硫?

喜欢喝葡萄酒的人发现,欧美的葡萄酒标签中的成分栏内几乎都含二氧化硫。这个常常跟酸雨、空气污染物相关联的"有毒有害的化学物质"怎么会堂而皇之地出现在了"典雅"的葡萄酒中?二氧化硫,葡萄酒不得不用葡萄酒是由葡萄汁发酵而成,葡萄汁中含有大量的糖,在发酵过程中酵母菌会把它们转化成酒精。所以,发酵越充分,转化就越完全,最后的成品中酒精含量就越高,糖含     

发酵营养剂NutrienFast添加时期对葡萄酒发酵的影响

在含糖量高、酵母可同化氮不足的葡萄汁中,研究不同发酵时期添加安琪发酵营养剂NutrienFast对葡萄酒发酵的影响。结果表明,在发酵第3天（糖消耗36.26%）、第4天（糖消耗到达44.18%）时添加发酵营养剂NutrienFast对葡萄酒发酵的影响最大,此时CO2累积质量损失最高,分别为129.62 g/L和128.82 g/L;葡萄汁中的酵母干物质含量达到最高值,分别为3.57 g/L、3.62 g/L;葡萄酒相对密度、残糖含量最低;酒精度最高,分别为16.5%vol、16.4%vol,酒精发酵完全（残糖＜4 g/L）,可有效解决或者预防葡萄酒的发酵停止或停滞问题。     

野生葡萄酒酵母的选育及其发酵过程中电导率的研究

对葡萄皮上野生葡萄酒酵母进行分离选育,并且利用WL培养基对所筛选菌株进行鉴定,获得了性能优良的葡萄酒酵母.利用所选育的葡萄酒酵母进行发酵实验,结果表明,其发酵效率高,葡萄酒品质较好.发酵过程中对发酵液的电导率和还原糖的变化的监测表明,在发酵前期,随着发酵过程的进行,发酵液中还原糖含量和电导率均下降;待还原糖含量消耗殆尽时,电导率骤然上升.该研究为工厂发酵过程中的在线监测提供了理论依据.     

糖分对葡萄酒发酵的影响

糖是葡萄酒发酵中酵母菌生长代谢所必须的能源,其种类和含量对酵母菌的发酵能力和代谢产物的生成影响很大。该文从糖种类、糖含量、加糖方式等方面对葡萄酒发酵的影响进行了综述及分析,以期为葡萄酒酿造中糖的选择和品质控制提供理论依据。     

葡萄酒与生活

一、葡萄酒的营养葡萄酒是葡萄发酵所得,它的营养成分绝大部分来源于葡萄,除酒精外,葡萄酒还含有糖、有机酸、蛋白质、氨基酸、矿质元素、维生素、酚类、芳香成分,这些物质除了赋予葡萄酒以丰富多样的香气,口味特性之外,还提供全面、均衡的营养。 1、产生热量:葡萄酒中的酒精、糖可以提供给人体热量,一升12度葡萄酒的热值为700卡,1度糖在体内完全氧化可产生37.56大卡的热量。葡萄酒的单糖可直接为人体吸     

果胶酶在葡萄酒酿造中的应用

众所周知,葡萄与其它水果一样含有大量的果胶,在葡萄酒酿造中果胶不仅影响葡萄的出汁率、葡萄酒的产量,而且还直接影响酒的质量。果胶是一大分子化合物,它的主要成份是半乳糖醛酸与其它糖所组成的杂多糖。由于它的存在葡萄出汁率降低,葡萄汁混浊,用未澄清的葡萄汁发酵还影响酵母作用,降低葡萄原酒的质量。     

昌黎产区赤霞珠干红葡萄酒的发酵分析

以2005～2007年昌黎产区优质赤霞珠为材料,对酿造干红葡萄酒过程中理化指标进行分析,评价以总糖、总酸、pH值和成熟系数为指标的葡萄质量状况;研究酒精发酵过程中的酒精产量和残糖含量.以及酒精发酵和苹果酸-乳酸发酵对葡萄汁和葡萄酒的总酸、pH值、挥发酸的影响;建立了葡萄酒潜在酒度与葡萄原料总糖之间的数学模型;讨论了昌黎产区赤霞珠葡萄的酒精产率以及葡萄酒总酸和pH值的调整问题.     

外源可发酵糖对葡萄酒挥发性化合物的影响

通过气相色谱-质谱法对4 种外源可发酵糖葡萄酒中的挥发性化合物进行定性定量分析。结果表明：添加外源可发酵糖,影响葡萄酒挥发性物质的特征;添加麦芽糖,葡萄酒中醇类、酮类、酸类、醛类、酚类和萜烯类的含量较高,酯类含量较低,而醇类和酯类的总含量在添加果糖和葡萄糖的条件下达到最大值。通过计算挥发性物质的香气活性值,确定20 种挥发性化合物为葡萄酒的关键香气物质。主成分分析和感官分析显示添加不同可发酵糖发酵葡萄酒的关键香气物质有显著差别,添加葡萄糖改善了葡萄酒的植物香和果香,风味强度最大,添加果糖和蔗糖改善了葡萄酒的青草香、花香、甜香和果香,添加麦芽糖改善了葡萄酒的花香、酯香、果香和甜香。     

高糖高酸葡萄汁发酵残糖的研究

以2011年昌黎地区发酵残糖较高的葡萄酒为原料,分析残糖产生原因,调整发酵工艺,完成了葡萄酒降糖目标,为用高糖高酸葡萄汁酿造葡萄酒提供了有益的建议.     

进口葡萄酒二氧化硫限量规定和检测方法的探讨

葡萄酒中二氧化硫残留指标是国家质检部门的严控指标之一.葡萄酒发酵过程中,人为或非人为的因素都会导致葡萄酒中二氧化硫的残留.本文旨在探讨国家标准在葡萄酒二氧化硫残留限量规定及在检测方法的选用上如何进一步规范统一,以避免因采用不同的标准而对结果判定错误的问题,为进出口葡萄酒一线检测工作提供 可靠的依据.     

Principal component analysis of the polyphenol content in young red wines

In the present study the content of 15 polyphenols was determined in 55 samples of red wines from different denominations of origin in the Canary Islands (Spain) using high performance liquid chromatography (HPLC) with UV and fluorescence detection. The most important differences in content among wines according to different categories (island, zone and denomination of origin) were established. In general, red wines from the Canary Islands had a content in polyphenols in the lower part of the range considered normal. The exception was quercetin, with a mean content (17.5 mg/l) higher than in other wines, which may be a peculiarity of these particular wines. The principal component analysis (PCA) technique was used to study the latent structure. A good differentiation among wines according to their production area was obtained using linear discriminant analysis (LDA).     

海拔对美乐和赤霞珠葡萄酒中酚类物质含量、抗氧化活性及酯类香气成分的影响

为研究海拔对大渡河干旱河谷地区美乐和赤霞珠葡萄酒的影响,以该地区海拔2280、2390 m葡萄园种植的美乐和海拔2280、2390、2600 m葡萄园种植的赤霞珠果实所分别酿造的干红葡萄酒为研究对象,对其理化指标、酯类香气物质含量、抗氧化活力及感官特征进行分析。结果表明:随海拔上升,2种(美乐和赤霞珠)葡萄酒的残糖含量降低,总酸、干浸出物、总酚、单宁、总类黄酮、总花色苷含量、色度、DPPH清除力以及铜离子还原力增加;2种葡萄酒酯类物质的相对含量随海拔上升呈下降趋势,但海拔对2种葡萄酒主要酒酯类香气的构成无影响,通过主成分分析,将葡萄酒酒样的酯类成分提取为3个主成分,累计贡献率达93.021%;葡萄酒感官得分随海拔升高而升高,但海拔过高对葡萄酒感官质量有负作用,海拔2390 m赤霞珠葡萄酒感官质量最佳;通径分析表明,总酚对葡萄酒感官质量有直接的重要作用。     

Polyphenolic composition of Spanish red wines made from Spanish Vitis vinifera L. red grape varieties in danger of extinction

Phenolic composition, chromatic characteristics, and antioxidant activity of young wines made from three minority red grape varieties (Moravia Dulce, Rojal and Tortosí) cultivated in the Spanish region of Castilla-La Mancha were studied over two vintages. Phenolic contents were affected by both grape variety and vintage, whereas phenolic profiles were mainly affected by grape cultivar, thus allowing their differentiation The anthocyanin profiles of Moravia Dulce and Tortosí wines were dominated by malvidin 3-glucoside, whereas peonidin 3-glucoside was in Rojal wines. The flavonol profile of Rojal and, in a lesser extent, Tortosí wines were dominated by B-ring di-substituted flavonols (mainly quercetin-type flavonols). In contrast, B-ring tri-substituted flavonols (mainly myricetin-type) predominated in Moravia Dulce wines. All studied wines had high quantities of total resveratrol, especially Rojal and Moravia Dulce wines, although they mainly occurred as cis-isomers. Rojal wines always appeared as the most different single-cultivar wines in all parameters in this study, being characterized by the lowest content of almost all families of phenolic compounds. With regard to the colour characteristics, all the studied wines had normal values to be considered young red wines except for Rojal wines, which should be considered as rosé wines. Finally, all wines showed remarkable antioxidant activity, closely connected with their phenolic content. The results suggest that Moravia Dulce and Tortosí grape cultivars could be appropriate raw materials for the elaboration of quality young red wines, whereas Rojal grapes could be for rosé wines.     

Differentiation of co-winemaking wines by their aroma composition

Co-winemaked Monastrell wines with Cabernet Sauvignon or Merlot, at different proportions have been studied for first time in terms of its odor activity value (OAV) in young wines, aging wines (after 9 months in French oak barrels) and bottled aging wines (aging wines after 6 months in the bottle). The co-winemaking wines showed a different aromatic complexity as they were fruitier and sweeter than the monovarietal ones, enhancing their aroma characteristics, being more evident at 60:40 proportion in case of Merlot for young and aging wines and Cabernet Sauvignon for bottled ones. In terms of extractable oak compounds, Monastrell–Merlot wines showed the highest values suggesting that they may need a shorter period within the barrel than Monastrell–Cabernet Sauvignon ones.     

Influence of the elaboration process on the peptide fraction with angiotensin I-converting enzyme inhibitor activity in sparkling wines and red wines aged on lees

The influence of some variables on the manufacturing process for sparkling and red wines on the angiotensin I-converting enzyme inhibitory (ACEI) activity has been studied. Ageing on lees significantly influenced the angiotensin I-converting enzyme inhibitor activity in sparkling wines. It reached maximum values at 9 months, decreasing afterwards. In red wines, the ACEI activity also increased in the wines aged on lees. In both wines, hydrophobic peptides were responsible for the ACEI activity. These peptides would make a much greater contribution to the total activity if present in higher proportions. It would therefore be advantageous to increase their concentrations in wines, either by using starting materials with high initial peptide contents or by using a highly autolytic yeast, giving a greater degree of hydrolysis of wine proteins, and higher concentrations of peptides with ACEI activity.     

Elemental characterisation of Cabernet Sauvignon wines using Particle-Induced X-ray Emission (PIXE)

The elemental composition of 2002 Cabernet Sauvignon wines from four different regions of Rio Grande do Sul state (Brazil) was determined using Particle-Induced X-ray Emission (PIXE) technique. In total, wines from 13 different vineyards were studied. Particular attention was given to wines stemming from Vale dos Vinhedos which is one of the most important wine producing regions in Brazil. Typical PIXE spectra consisted of elements with atomic number between 11 and 38 such as P, S, K, Ti, Mn, Fe, Cu, Zn and Rb. Physicochemical variables such as volatile acidity, alcohol, pH and dry extract were also determined for some wines. Variations in the elemental concentrations among wines from Vale dos Vinhedos and from different regions were observed. In general our results are in good agreement with previous measurements of Brazilian wines. With respect to European wines, our results are characterised by relatively low concentrations of Cu and Zn and high concentration of Rb.     

Comparison of amino acids,biogenic amines and ammonium ion of wines made of different types of fruits

Amino acids, biogenic amines and ammonium ion are the primary nitrogen sources in fruit wines. Compared to grape wines, our knowledge to their profile in wines made of other fruits is very lack. Fourteen wines made of nine kinds of fruits together with seven grape wines were selected to compare their nitrogen component profile. White grape wines possessed the highest level of total amino acids, followed by red grape wines and then the wines made of the other fruits. Red grape wines contained the highest level of biogenic amines, followed by white grape wines and the wines made of the other fruits. Ammonium ion was also found to be higher in the wines made of grapes. Principal component analysis revealed that the obvious separations existed among the wines made from different types of fruits, indicating that these nitrogen compounds could be served as the indicators to differentiate different types of fruit wines.     

一种低度芡实酒理化功能性质分析

为充分利用芡实这一地方特产资源,拓宽其应用领域,将一定比例的芡实与糯米混合发酵,制备一种低度芡实酒,对其主要营养组分、酚类物质含量及其体外抗氧化特性进行了分析。结果显示,所得芡实新酒和陈酿1年的成熟酒中均含有丰富的蛋白质、必需氨基酸和总酚,风味浓郁,相关指标达到了一级半干型黄酒国家标准。HPLC分析显示,芡实酒中含有较丰富的多酚类物质,如没食子酸、阿魏酸、槲皮素和芦丁等。在陈酿期间,芡实新酒中的芦丁几乎全部转化为槲皮素。此外,芡实酒显示出很强的体外抗氧化活性和亚硝酸盐清除能力,这与其中丰富的还原糖和多酚含量密切相关。研究表明,所得芡实酒营养丰富、具有较强体外抗氧化活性。     

2019年,你都错过了哪些有趣的酒?

过年,我们举办了7场试饮会,为读者们挑选了数十款有趣、面向不同消费场合的酒款。这一期,我们精选了2019年试饮会上评分最髙,又或者是最受欢迎的酒款。现在,就让我们一起来看看这些酒款里面,有哪一款会让你有心动的感觉呢?     

The influence of pectolytic enzyme addition and prefermentative mash heating during the winemaking process on the phenolic composition of Okuzgozu red wine

The effects of pectolytic enzyme addition and mash heating prior to fermentation on the phenolic component of Okuzgozu red wine during the winemaking and ageing processes were investigated. In general, the highest concentration of total phenolics was found in the mash-heated wines, whereas the total flavan-3-ol and total anthocyanin contents in all of the wines, decreased notably during the winemaking and ageing processes. As determined by HPLC, hydroxycinnamic acids were the major phenolic acids in the red wines. After 6 months in the bottle, the enzyme-treated wines had lower phenolic acid concentrations than had the control and mash-heated wines, but no significant (p < 0.05) differences were found in the concentration of total phenolic acids between the control and mash-heated wines. All of the phenolic acid levels decreased with the winemaking and ageing processes whereas only gallic acid increased. The wines treated by the pectolytic enzyme addition had a lower monomeric flavan-3-ol content than had the other wines, and the amount of monomeric anthocyanins extracted did not increase with the addition of enzymes.