Wine Basics - Making Red Wine

The main difference between making red wine and making white wine is in the skin contact. Because all grape pulp, including most red wine grapes, is white, skin contact is essential. The skins of black grapes are important because they contain "phenolic" compounds: a complex mix of colouring agents, flavouring agents and a substance called tannin. Besides colour, tannin is the essential difference between red and white wines. It is a powerful preservative, and since red wines are often made to mature over many years, tannin is required to ensure the wine does not grow old prematurely. Tannin also has a taste- slightly bitter- and an effect that dries and puckers the mouth. Another substance containing large quantities of tannin is cold, stewed, strong tea. A mouthful of that will give you an idea of what tannin is all about.

The classic red wines of Bordeaux and Burgundy (and their new world counterparts) are made with a hefty dose of tannin that helps to preserve the wine along with acid, and balances against the other flavour components of fruits, minerals, earth and wood. Such wines are designed to improve over many years until they reach their peak- the point when the tannins have mellowed or softened and the components have integrated perfectly. You need patience, suitable conditions and a healthy bank balance to get into the business of cellaring the great red wines until they reach their peak.

Red wines destined for early or short-term drinking (and not for "laying down") are made with little or no tannin in their composition. Traditionally these were lesser, peasant wines, made to be drunk with the daily meal and without ceremony. However, tastes and needs change, and many fine, modern wines are made for immediate consumption. Since these wines don't need to last several years, the bitter tannins are excluded and the wine tastes fruity, fresh and approachable upon release. More recently, many high-quality wines have been made with a lower tannin component to allow them to be drunk sooner. Innovations, such as the roto-fermenter invented in Australia, allows the winemaker to macerate the juice so as to extract as much colour as possible from the grape must, without increasing the amount of tannin in the final product that regular maceration produces.

Making red wine

The winemaker has at his disposal a far greater range of techniques, and must make a far greater number of decisions, when making a red wine. The process is essentially the same as the white wine process: gathering the grapes, fermentation, maturation and bottling. At various stages the winemaker can intervene to change the style of the wine he is making.

The grapes are crushed, but a proportion of the stalks may be left in place. The resulting mash is run straight into the fermentation tank without pressing. Unlike white wine, the skins are part of the fermentation. Fermentation temperature varies between around 18° and 28° celsius, as does the length of fermentation between a few days and six weeks. The fermentation vats may be concrete, steel or, traditionally, oak.

The high-quality "free run" wine is poured straight into barrels or stainless steel to rest and mature. The remaining mulch of juice, skins, and stalks is pressed, to extract a strong, tannic liquid known as "press-wine", a proportion of which is often blended back in at a later stage to add body, tannin and strength to the finished wine.

Most of the great red wines are matured in oak barrels. This is an expensive and labour-intensive process. Oak from ancient French forests is generally agreed to be the finest, imparting a subtle vanilla, toasty flavour. Each 200-year-old tree produces only 2 barrels, so they are expensive at $750.00 each. The forests are managed with a re-planting policy. American oak is also very popular and is cheaper. It is regarded as imparting a "bigger", less subtle, spicy flavour to wine. Oak from the Ukraine, Poland and Slovenia is very old and fine and is the cheapest of all, but many experts find it is not flavourful enough.

Prior to bottling, the wine must be cleared. Traditional fining is widely practiced, but use of filters and centrifuges to remove absolutely all micro-solids from the wine is highly controversial. Wine is a living thing. Tiny biological changes take place over years as the wine matures in the bottle, and many people believe that heavy-handed filtration destroys the wine's ability to age and improve. This is why many red wines must be decanted before serving: to run the wine off from solid deposits.

Factors affecting the styles of red wine

The winemaker has a great deal of freedom to make choices in making a red wine. His decisions will be affected by the style of wine he is aiming to make, and the raw materials the vintage has given him to work with. Some of the options open to him are listed below:

  • In most areas the vineyards may be planted with a variety of different grapes. Since many of the great red wines are blends of one or more grape variety (Bordeaux, Châteauneuf-du-Pape, etc.) he first can choose the proportion of each grape he will plant and use
  • Every noble grape grown has had a clone produced to deal with the vagaries of the varied climates around the world. He must decide, based on the climate of his vineyard, which clone he will choose to use for his wine
  • Each vintage results in different ripeness for each grape variety. This uneven ripening time will factor heavily into the decision as to which grapes will provide the greatest proportion of juice to the blend
  • He can decide to use whole bunch fermentation, which includes stalks and stems, or he can use individual grapes
  • He can choose the proportion of tannic stalks to include in the fermentation
  • He can choose the type of fermentation - regular versus carbonic maceration
  • He can "cold soak" the grapes- crush them lightly and allow them to sit for a week or two at a temperature too low to ferment, but still allowing colour and tannin to leach from the skins
  • He can choose cement, steel or oak for fermentation tanks
  • He can choose the type of wood he wants to ferment his wine in
  • If he chooses oak, he can choose new oak, used oak, oak chips, oak tea bags, oak flavouring or oak staves or planks. He must also choose where the oak comes from, i.e. France, USA, Slavonia, etc
  • He can choose the temperature and length of fermentation
  • He can choose when to remove stalks and skins during fermentation
  • He can choose how to mature the wine (if in barrel, taking into account all the variables of type of oak, level of toast, age of barrel, etc.)
  • He can choose the length of maturation (usually between 8 and 24 months, though some fine wines- sherries and Riojas for example- can spend up to 40 years in oak!)
  • He can choose to produce a 'Reserva' wine and age it in the bottle for many more months
  • He can add some of the press-wine back in to the blend
  • He can blend the wines from different grapes and different casks
  • He can choose the method of fining and/or filtration
Special considerations in making a fine red wine

As well as offering a world of choices to the winemaker, red wine also offers extra challenges and complications he must overcome to make a great wine.

  • Firstly, he must balance the colour and tannin extraction of the wine with its fruit and freshness. Wines made with too much tannin may never reach a peak where the natural fruit and flavours of the wine re-emerge as the tannins subside
  • Carbon dioxide given off during fermentation causes the skins to float to the surface of the tank and form a "cap". This must be regularly submerged to ensure the wine keeps extracting elements from the skins. This can be achieved by "pumping over" juice from the bottom to the top of the tank, by manually pushing down the cap, or by fitting a mesh filter below the surface of the wine
  • He must judge the correct levels of new/old oak and toast level
  • For all the time the barrels are in the cellar the wine must be "racked": wine is drawn from one barrel into a clean barrel. Only around 90% of the barrel is drawn off, the remaining 10% is full of dead yeast cells and is discarded. This process is carried out every 3 months or so and the fresh barrel must be topped back up to 100% with reserved wine
  • Malolactic fermentation must be induced
  • Decisions must be taken on blending, fining and filtration