Thursday, 6 March 2014

Lovely Lees

I have decided that I have a love-hate relationship with lees. They are so important for providing some complexity in Chardonnay, yet at the same time they really are a pain to clean out of the bottom of a tank!

In 'wine-speak'  complexity is used to describe the dimensionality, or layers present in a wine.  Less complex wines are generally very fruity and simple, but as the wine becomes more complex, it is possible to identify many different aromas and other unique characteristics.

So why exactly do the lees add complexity to a wine?

If wine is left in contact with its lees for a certain amount of time, proteins from the dead yeast cells will be released which impart sensory changes in the wine.  These help enhance the body and mouthfeel of the wine as well as decreasing the perception of bitterness and astringency.  

Winemakers do have to be careful with the use of lees, as they can also have a negative impact due to some chemical side reactions which can lead to highly undesirable smells such as rotten egg.

The photos below show a lees rake that is used to remove lees from the bottom of a tank that has just been emptied of wine.  It's somehow enjoyable raking through the sloppy, thick goo, but the smell is not great!