Wine Trivia Tuesday | LEES (Or sur lie)

I'm a big fan of buttery, brioche, mousse, biscuity characters in white wines and Methode Cap Classiques.

I can't help but think of warm, freshly baked breads or cookie dough when I smell such aromas waft across the top of a glass.

There are a number of ways a winemaker brings out these characteristics in a wine, and one of them is leaving the wine to mature 'on the lees'. Or sur lie as the French would say.

If you take the time to read the tasting notes on wines, specifically the likes of Chardonnays, some Sauvignon Blancs and definitely Methode Cap Classiques here in South Africa, you'd have come across the term 'lees' before. 

What are lees?

My thoughts run wildly in the direction of a 'sediment', in layman's terms. During the fermentation process yeast is either added to the wine or natural yeasts found on the grapes, stalks, etc, come into contact with the juice. These yeast cells get the fermentation process started, where they convert the sugar  found in the crushed grape juice into carbon dioxide, and more importantly, alcohol.

Once the yeast has consumed all the sugar in the wine the dead yeast cells will slowly drop to the bottom of the barrel. This will include small bits of grape skins and other insoluble organic matter found as part of the maturation and winemaking process. 

This 'matter' drops to the bottom of the barrel, or tank, where it lies and can either be filtered out of the wine, or left to influence the wine.

The larger of these dead yeast cells are called the gross lees, whereas the finer cells are known as the fine lees. Winemaker's may filter out the gross lees to be left with the fine lees which offers more subtle, smoother component to the wine, than do the gross lees cells.

So why leave the lees in the fermentation tank, or barrel?

The lees give a little extra 'weight' to the style of the wine. In sparkling wines the lees gives you that delectable mousse, cookie dough aroma which you'll often find on the nose. I love it because it rounds the wine off well, dampening the higher acidity a little, just enough to make the sipping experience akin to biting into a hazelnut-flavoured macaroon.

A unique character which is an outcome of leaving a white wine on the lees is that it can come across on the nose as slightly oaked due to nutty, cookie dough characters. These aroma profiles can sometimes, initially, be mistaken for the wine having spent time in oak barrels, but in fact are just the result of longer lees contact. The difference is that instead of that heavier palate you'd expect from a barrel matured white wine, you'll still find fleet-footed acidity rounded off with a riper fruit-style on the finish. 

Wines can spend from four months up to six years on the lees. Methode Cap Classique's have to spend 12 months on the lees as part of the regulations surrounding the production of sparkling wine in this French style.

Most South African white wines which have been produced with time on the lees, as far as I have noticed, are anywhere from four to 11 months, give or take a few months. 

The best way to understand how lees can alter a wine's style is to taste the difference between two wines. Therefore, I've put together a mixed case of the following two wines for you from a very well known, and respected, South African vineyard - Kleine Zalze in Stellenbosch.

Kleine Zalze Wines


Included in the case are three bottles of each of the above two Sauvignon Blancs, which have both spent time on the lees, however different lengths of time. The Family Reserve Sauvignon Blanc Sur Lie includes less filtration meaning a greater influrance of the lees on the wine in-bottle.

Grab a case, invite some friends over and enjoy learning something new about how lees contributes towards the end result we get to enjoy in-bottle. 

Click here for more details on the Kleine Zalze 'Lees is More' Mixed Case.