From the fermentation and filtration of the juice of grapes of the same variety – a custom that, according to archaeological evidence, humanity has been eating since 6000 BC Red wines are made from dark grapes, such as merlot and cabernet sauvignon, while green grapes, such as chardonnay and muscat, give rise to white wines. The yield varies from one winery to another, but Embrapa estimates that 1.5 kilos of grapes are needed to obtain 1 liter of wine. In 2008, national production reached almost 335 million liters.
From the vine to the table
World wine market moves more than 230 billion reais per year
1. Harvesting is manual in most wineries. Bunches are removed with special scissors and placed in plastic or wicker boxes. In mechanized harvesting, a tractor passes over the vines, shaking them to make the grapes fall into a built-in reservoir.
2. In the canteen – the shed where the wine is processed -, the grapes go through the destemming machine, where they are crushed. The handles separate from the must – mixture of skin, pulp and seeds – and the juice begins to ferment due to the contact of yeasts in the skin with the sugar in the pulp.
3. To produce white wine, the rind is discarded. In reds, everything goes into a maceration tank. In this process, the anthocyanins, substances that give color to the peel, begin to color the liquid. In four days, the juice already has a very vivid color.
4. In addition to producing alcohol, fermentation releases carbon dioxide, causing the wort to rise and pool at the top of the tank. To spread the color evenly, the bottom liquid is pumped up twice a day in a process called pumping over.
5. After about four days, pumping over is stopped to isolate the wort from the liquid. It’s time to open a tap at the bottom of the pump-over tank and release the juice. The remaining must still goes through a press, but it will generate a wine of inferior quality.
6. Natural fermentation is boosted with yeast dissolved in water. The process heats the tank up to 30ºC and is monitored by technicians who take daily samples. For two to ten days, the sugar turns into alcohol until it reaches the desired level – between 7 and 14% of the volume.
7. Before going to the bottles, the wine passes through a series of filters of different porosity to get a clear appearance. Filtering retains from coarser residues, such as pieces of bark, to microorganisms used in fermentation
8. Filling and labeling are often automated. The cork, usually made from oak bark, is custom-made. As it suffers corrosion of 1 mm per year, the producer needs to calculate its length according to the estimated time for storage and maturation of the wine
Consultancy – Luiz Antenor Rizzon, Agronomist and Researcher at Embrapa Grape and Wine Data Brazilian Union of Vitiviniculture, Brazilian Institute of Wine and Vinexpo