Red wine is made exclusively from blue grapes. In contrast to white wine, the seeds, skins and stems are also fermented during pressing. These contain valuable tannins, flavorings and colorings that already begin to develop during the mash fermentation. A north-south gradient can be identified in the distribution of white wine and red wine regions, which is due to the fact that the red grapes prefer to thrive in very warm regions. In the north (besides beer) people tend to drink white wine and in the south they tend to drink red wine. There is also a special type of wine, the rosé wine.
Compared to white wines, red wines have less acidity but significantly more tannins. The alcohol content is also slightly higher. During the mash fermentation, the fructose turns into alcohol. The heaviest red wines can develop an alcohol content of up to 15% vol. The aroma spectrum of red wines is diverse. Typical are the taste of wild berries and cherries. Other flavors include mocha, vanilla, chocolate and cinnamon. If the fermentation is stopped early, red wines develop into a light thirst quencher. On the other hand, if the fermentation lasts longer, complex, heavy and alcohol-rich red wines develop, which are of particular interest to gourmets.
Riserva is an addition in the Italian wine classification. He points out that wines must meet certain criteria in terms of storage, cultivation and aging, such as longer storage than the same wine without the additive. The next higher quality level for the addition is riserva speciale.
The grapes are obtained from the noble vine and used as fruit (table grapes), raisins and for wine production. About 8,000 to 10,000 grape varieties are known worldwide, of which only 2,500 are approved for wine production. This illustrates the strict quality criteria of the wine, in order not to dilute the most complex drink of all time for the discerning connoisseur. In Germany, 140 grape vines are cultivated, of which Riesling and Müller-Thurgau (Rivaner) are the best known.
A pyramidal hierarchical gradient can be observed among the grape varieties. Only about 24 of the approximately 2,500 permitted grapes are of market importance. The 50 most popular grape varieties account for 95% of the acreage. In total, the area for worldwide wine cultivation is approx. 7.9 million hectares, in Germany it is just over 100,000 hectares.
The noble grapevine is one of the oldest plants on earth. Its age is estimated by scientists to be around 100,000,000 years. While the Egyptians used to be considered the first people to cultivate wine, numerous new finds could shake the old knowledge. According to the current state of information, the first evidence of viticulture in the South Caucasus is in what is now Armenia and Georgia. The sources could point to the year 5800 BC. be dated. Sources from Sumeria in Mesopotamia from the year 5000 BC follow. While the Egyptians were cultivating wine, it was of the utmost importance as a luxury food in ancient Greece and Rome. With Dionysos and Bacchus, wine was even given its own gods. In the Middle Ages, Charlemagne provided for the first wine ordinances, while in the age of the colonies other important overseas cultivation areas could be gained.
By crossing, selection and mutation, the vines could be significantly improved in the past millennia. Other vines were lost over time due to drought, disease and cold. The individual grape varieties differ in quality and in many other properties.Some have distinctive unique selling points such as the nutmeg taste of Muskateller or the spicy Gewürztraminer, whose special features are already expressed in the name. Important white wine vines are Chardonnay, Gewürztraminer, Muskateller and Savignon Blanc. For red wine, these are Cabernet Sauvignon, Grenache, Merlot, Nebbiolo, Pinot Noir, Sangiovese, Syrah, Tempranillo and Zinfandel. The sub-science within vinology that deals with the individual grape varieties is ampelography.
Remontage refers to a pumping process during mash fermentation to flavor the wine. The aim is to bring the must into contact with the berries, skins and stalks so that these components of the wine, which contain a lot of tannin, can release their aromas, colors and fragrances (bouquet) to the must. During fermentation, these tend to rise and form a so-called marc cap.
The reassembly process has to be carried out several times because the must flows down again after pumping over. Only when the process has been repeated several times have the solid components of the berries released enough aromas into the must. The alternative to achieve the same effect is the pineage.
In the language of wine, residual sugar refers to the portion of the remaining sugar in the wine that was not fermented into alcohol and carbon dioxide after fermentation. In order to increase the proportion of residual sugar in sweet wines, cellar masters have various methods of stopping. These methods consist of adding alcohol, which stops yeast activity, adding sulfur dioxide, cooling and filtration, including subsequent sterile filling.
The residual sugar consists mainly of fructose, as this sugar ferments faster as glucose. Non-fermentable sugars, the pentoses, are also contained in the residual sugar. The natural limit of sugar fermentation is 0.7 g/l. If the amounts of residual sugar are very small, they no longer produce a sweet taste, but rather a soft and mild undertone. Cellar masters use filtration and pasteurization methods to prevent secondary fermentation, which causes cloudiness and wine defects.
Wines are divided into dry, semi-dry, semi-sweet and sweet with regard to their residual sugar content. In Germany, the criteria are:
Dry wines: up to 9 g/l residual sugar if the acidity is less than 2 g/l.
Semi-dry wines: up to 15 g/l.
Semi-sweet (sweet) wines: up to 45 g/l.
Sweet wines: over 45 g/l.
Reductive expansion is the alternative to oxidative expansion. While a low level of diffusion with oxygen is desirable in the case of oxidative expansion, this is avoided in the case of reductive expansion. The wine matures in tanks, for which modern stainless steel tanks are now available in industrial production. Smaller winegrowers also use bottles, where the small amount of residual oxygen in the neck of the bottle is quickly consumed. Carbon dioxide, nitrogen and argon can also be used during reductive aging to create an inert atmosphere.
Reductive aging is usually used with white wines and sparkling wines, giving the wine a fresher, clearer and fruitier flavor as it ages -a sparkling taste is given with a flowery bouquet. A strictly reductive white wine is usually conspicuously light with a color spectrum between white and light yellow. While the strictly reductive method was popular in the 1980s, white and sparkling wines are now more likely to be kept in a moderately reductive state. The reason for this is that the wine becomes too superficial with too little oxygen and also reacts too sensitively to oxygen contact after filling.A little more oxygen, on the other hand, gives the wine more complexity, depth and structure
Just a few years ago, hardly any German knew what a rosé wine was. This has changed in recent years, because as in other countries, the rosé wine, the tradition of which is based in the Provence wine region, is popular. There, 80% of all wines are processed into rosés. In Germany, the proportion of rosé wines sold has quadrupled in recent years from 2% to 8%.
A rosé uses red grapes just like a red wine. However, the production process is similar to that of a white wine. With a rosé wine, the grapes are allowed to lie on the mash for a maximum of a few hours in order to absorb at least some of the colour, aroma and tannins. If this happens, it is called the maceration method. If this is not done at all, the pressing method is used, so that the rosé wine only gets a slight pink tinge. The third production method, the saignée method (French: bloodletting), is similar to maceration. The rosé wine is created as a by-product of red wine production by removing the rosé wine from the mash after a predetermined time. The rest of about 80% remains and is further processed into red wine. This method is done so that the remaining red wine can absorb even more extract and color than usual due to its smaller volume. It tastes more concentrated and intense afterwards. The fourth method, a blend of red and white wines, is banned in the EU and may only be used with sparkling wines.
A rosé wine varies in color from a pale pink to cherry red, depending on the grape variety and how it is made. Due to their low tannin content, rosé wines are very refreshing and popular summer wines. They like to be served chilled. Their taste is similar to light red wines.
Pure cultured yeasts
Pure cultured yeasts were developed from the 1970s onwards. They increasingly replaced natural fermentation (spontaneous fermentation) with controlled conditions. The types of yeast developed for this purpose are pure (whereas natural yeast is always a mixture of several types of yeast) and cultured. Thus, yeast types could be obtained that were optimized for the wines and have ideal conditions for the fermentation process. In some cases, different pure culture yeasts are used for different grape varieties, depending on which yeast type best suits the grape variety.
In recent years there has been a religious battle between winegrowers. Some winegrowers swear by the new technology of pure cultured yeasts and consider them superior to natural yeasts. They also refer to the elimination of risks that are repeatedly triggered by spontaneous fermentation. Other winegrowers expect a greater variety of flavors from resorting to traditional spontaneous fermentation and are open to the risks, which can also have positive effects. They see more opportunities than risks and complain that the standardized use of pure culture yeasts has led to a uniformity in wine taste. Ultimately, the form of fermentation used is a matter of personality and style, where there is no right or wrong.