Production of White Wine
The steps of making white wine are:
- Grapes are picked and sorted, removing the rotten ones and quickly taken to winery.
- Grapes are crushed and allowed to macerate for 24 hours in a cool tank for heavier bodied wines.
- The solid material is passed trough the press where the juice is drawn off.
- Sulphur is added to kill bacteria and prevent oxidation
- Solids suspended particles are separated either by allowing the juice to rest in wooden barrels or by use of centrifuge.
- The juice is fermented. Naturally occurring yeast may be allowed to ferment the juice. Fermentation may be slow or fast depending on the temperature. If it is warm (18 – 25 degree Celsius) is faster. Cool means 18 degree Celsius. Cooler fermentation results to fruitier but less complex wines. Fermentation may take place in oak barrels or steel tanks.
- Powdered sugar or concentrated grape juice may be added if there is insufficient grape juice to increase the final alcohol level. This process is known as Chapitalisation, and is carefully done, as it is not permitted for many fine wines.
- The next step is to allow wine to undergo Malolactic Fermentation. This is natural conversion of (apply) malic acid to lactic acid.
- The wine is clarified either by help of egg whites that drags solid particles or ’lees’ down to the bottom of the vat. This process is called Finning. Then the wine is Racked, i.e. transferred into other vat leaving the lees behind.
- The wine may be allowed to mature for a while in the vats.
- Sulpher is added before bottling to protect and stabilize the wine. The dose is carefully judged to prevent the wine from suffering “bad egg” smell if more is used.
- The wine may be allowed to bottle age for some time before marketing.