Sur Lie Aging Explained

Sur Lie Aging Explained

What is Sur Lie Aging? Sur lie aging is the process of allowing a finished wine to continue to sit on the lees in order to extract flavors. Recently we explored the fact that there are two different types of lees. There are the grape lees (coming from the fruit) and the yeast lees (you guessed it, from the yeast). Each of these can be used in sur lie aging and each will produce different results. Aging wine on the grape lees is something to be undertaken with extreme care as this lees can easily spoil a wine if not done properly. When done correctly though it can lead to a wonderfully complex wine. Yeast lees on the other hand is the more common lees to perform sur lie aging with. As the yeast decomposes it can impart nut, bread, and yeast flavors to a wine. Different yeast cells can contribute different flavors too so you’re not guaranteed to get the same thing from all yeast strains. The remainder of this article pertains to aging on the fine lees only. How does Sur Lie Aging Work? During sur lie the lees cells break down (i.e. decompose) into simpler compounds. This releases sugars and proteins that interact with the wine chemistry. There are also flavor and aroma compounds that get released. As the proteins are released they bind with tannins in the wine. This is good for a white wine as you don’t want tannins in a white. However, for a red wine this can be problematic as it is the tannins that go a long way in determining the aging potential of the wine. For this reason red wines are usually not aged this way while white wines often are. The deciding factor depends upon the intentions of the wine maker. If the lees are left undisturbed in the bottom of your aging vessel for too long they can start to form some nasty sulfur flavors and aromas. To keep this from happening you need to stir the lees regularly, a process called battonage. Stirring the lees keeps hydrogen sulfide from forming as quickly and ensures that your wine gets maximum exposure to the cells and the compounds they’re decomposing into. Things to Watch Out For As you proceed through the sur lie process be sure to pay special attention to the flavor profiles of your wine. You can over do this and end up with off flavors. If at any point you experience sulfur like flavors like rotten eggs, rack off the lees immediately. The sooner you take action the better your chances are of being able to deal with these off flavors. Taken too far and your wine won’t be drinkable. When to Age on The Lees Preparation for sur lie aging begins as fermentation is wrapping up. The lees should be stirred up every two to three days for the last bits of fermentation. Once fermentation has ended continue to stir the lees once or twice each week for a period of six weeks or so. After that stir it up monthly. Some wine makers prefer...

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