Overview

Red wines are made entirely from red grapes varieties containing anthocyanins and pigmented tannins in the skins. The lightest most elegant red wines are centred around primary fruit character and a delicate, soft texture. Other red wines designed for cellaring can be rich and full-bodied with dark colour and intense chewy tannins. Maturation is a crucial stage in the production of full-bodied red wines whereas lighter reds are bottled earlier to capture freshness.

The Big Picture - The Red Raw Ingredient

The key difference between white and red winemaking is that red wine is made by fermenting the juice, skins and seeds together and then pressing the wine.  Depending on the style of wine being made and the condition and ripeness of the stalks, whole bunches of grapes are sometimes fermented along with de-stemmed and/or crushed berries. Again, depending on the grape variety, the style of the desired wine and the condition of the fruit, the winemaker chooses whether or not to crush the berries and to what degree.

Crushing and Destemming

Fermentation, Extraction and Maceration

Red wines are fermented at higher temperatures than whites, typically in the range of 28 to 30 degrees Celsius, and the total period of maceration varies tremendously, from as little as two to three days to one month or more, depending on the desired wine style.
Prior to the commencement of fermentation, the temperature of the must can be adjusted to allow a period of cold maceration. This allows the gentle extraction of compounds from the skins without the presence of alcohol (a powerful solvent) and is particularly important in preserving the delicate character of lighter red wine styles.
Because the extraction of compounds from the red grape skins is the key to red winemaking, the correct ratio of juice to solids (skin, pips and sometimes stalks) during fermentation is crucial. To regulate this, juice can be run off prior to fermentation and vinified separately as rosé.
There are various styles and sizes of fermentation vessels available, ranging from rotary fermenters (rotating stainless steel barrels) to large static vessels. Most high quality red wines are fermented in open, static fermentation vessels to allow greater control of the extraction process.  Once yeast cells are active and fermentation is underway, the solids (skins and pips) are pushed upwards by carbon dioxide gas, forming a solid layer known as the cap. Winemakers then carefully manage the extraction of compounds from the skins and pips, particularly tannins, anthocyanin pigments (that give red wine its colour) and compounds that form flavours and aromas.

Red Wine Making Process

Full-bodied red wines warrant deeper extraction of these compounds and lighter reds suit a gentle, softer touch. For extremely delicate extraction, the cap is plunged down into the fermenting juice using a plate on the end of a pole, known as hand-plunging or pigeage. This process is now mechanised in some wineries.
Alternatively, juice can be drained from the bottom of the fermentation vessel and pumped over the top of the cap by hose, known as rack and return or it can be continuously pumped over. Another method uses wooden boards to hold the cap submerged beneath the juice. Each of these techniques, used in isolation or combination, will have a strong influence on the structure of the finished wine (ie how rich in colour, tannin and ultimately flavour the wine will be).