From Fermentation to the Bottle

After fermentation, wines may go through these processes to different extents, or even not at all.

Racking

Racking is the process of removing sediment or 'lees' from the wine. This is done by allowing the wine to settle for a month or two, the wine is then transfered to a new barrel allowing the sediments to be left behind. This process is done as it is needed. If the wine is left 'on the lees' for more than three months, it can add bad flavours and odors to the wine as the yeast cells start to rot. This is why racking is important.

Secondary Fermentation

The winemaker may choose to allow a wine to undergo a second fermentation which occurs due to malic acid in the grape juice. When malic acid is allowed to break down into carbon dioxide and lactic acid, thanks to bacteria in the wine, it is known as 'malolactic fermentation'. This can impart additional flavor to the wine, a 'buttery' flavor in some whites is due to this process. Since malic acid, think green apples, is perceived as more sour than lactic acid, think milk, the process also reduces the perceived acidity of the wine.

Malolactic fermentation is much more prevalent in red wines than in whites, with the smell of apples in white wine denoting the presaging the presence of malic acid.

Aging

Usually done in oak barrels. Click Here to see the section on Oaking

Fining and Filtering

After fermentation, there still may be a lot of stuff floating around in the wine which some winemakers want to remove. Fining uses a substance, for example egg white or gelatinor bentonite, to capture the materials floating in the wine. The materials collect at the bottom of the container and are easily removed.

The process for removing this is called 'clarification' and there are various ways for the wine to do this. For example, strain the wine through something like cheese-cloth.

Return to the Wine Guide Contents
A brief history of Wine | Growing Vines and Grapes | Harvesting | Making Red Wine | Making White Wine | Making Rosé Wine | Making Champagne | To Oak or not to Oak? | From Fermentation to Bottle