brewergregg wrote:Depending on who you listen to, you should either rack your wine alot or alittle. I assume we do it mostly to separate the wine from the lees. My question is why might it be important anytime before bottling. What effect does sitting on your lees have on the end product? Is there a good reason to worry about it?
A couple of advantages of racking:
1) to seperate wine from sediment for clarity
2) to seperate wine from sediment to avoid off flavors from yeast autolysis (when yeast cells run out of food they can start 'yeast canibalism' which can produce an off flavor/aroma).
3) to produce some disturbance which can help gas out some off aromas/flavors (e.g. sulfur compounds)
4) to produce some disturbance which can help gas out carbon dioxide so the finished wine is not carbonated.
A couple disadvantages:
1) oxygen pickup which can shorten the shelf life of the wine
2) your time and effort
In some white wines, the wine is left on the sediment and stirred (sur lees) to pick up some yeasty complexity.