Rosé wine is an alcoholic beverage made from maceration grape must with pomace and subsequent alcoholic fermentation of dark-coloured (red) grape varieties of Vitis vinifera genus. Any red variety is essential to obtain a rosé or claret wine, however the most commonly used are: Garnacha and Tempranillo in Spain; Merlot, Syrah and Cabernet Franc en France.
How is rosé wine obtained?
There are two methods to produce rosé wine: By pressing, consisting on filling a press with whole, uncrushed stemmed grapes with a maximum of 20% white varieties if desired. The press should remain filled for 6 to 24 hours so must macerates with the pomace. Sulphur addition is recommended to avoid oxidation and dry ice to cool the harvest. Then the actual pressing is performed, in the first cycles must is richer in anthocyanins (colouring matter) and aroma, while the last must has higher tannins content, contributing to final wine astringency. Must is then vinified as if it was white wine, with the racking, alcoholic fermentation, stabilization and filtering before bottling. Rosé wines produced like this have a light, orange colour, similar to salmon or onion skin. The second method is draining, following the same steps as for red winemaking. Harvest is de-stemmed, crushed and pumped into stainless steel tanks where musts would macerate at cold temperatures for 24 to 36 hours. Accordingly to the maceration period musts have a more or less intense raspberry colour. Maceration process is interrupted by draining or straining the must from the solid pulp through a sieve. The resulting liquid is racked into a vat for the alcoholic fermentation.
Regardless the method used, either pressing or draining, a high quality rosé wine requires special care and a delicate process. Remember it is absolutely prohibited to blend white wine and red wine to obtain rosé wine.
On the other hand, all the different treatments rosé wine can undergo (malolactic fermentation, tartaric stabilization and filtering) are optional, there are no established procedures, so everything relies on the variety nature, the vintage, type of wine desired and the target market.
One of the golden rules not to forget during winemaking is the ceaseless care and protection of wine against oxidations, as we look for bright, rich colours and fruity primary aroma, so sulphur addition is very important after alcoholic fermentation.