Most of us expect that when we pour a glass of wine it will be clear and bright. Unfortunately when a wine finishes fermenting it is far from so. It is cloudy and hazy with suspended particles of dead yeast cells, fragments of grape pulp, skins and stems, tartrates and colloids (tannins, proteins and phenolic particles).
To render a wine clear and free of suspended particles, it is clarified. Most wines, if left long enough will self-clarify by gravity and the particles that fall to the bottom can be siphoned off. However, in the interests of efficiency and in getting the wine to market in a timely manner, most winemakers help the process along, by using a variety of aids such as fining agents.
Egg whites, or albumen, is one such fining agent used to clarify red wines. Egg whites are particularly good for removing tannin particles, especially green or harsh tannins, rendering the wine more round and soft in texture. Depending on the size of the egg it takes between 3 and 8 egg whites to fine a 225 L barrel (barrique) of red wine.
That leaves a lot of egg yolks doesn't it? You often find that eggy desserts or cakes are traditional or customary in regions noted for red wine production. For example let's take Bordeaux, where you can find 'canelés' everywhere. These are small cylindrical custard type cakes with a dark caramelized crust. These are delicious with your morning or afternoon coffee — if you like eggy things.
It is important to point out that fining agents are not wine additives and typically precipitate out with the hazy molecules during fining.
Mary Gorman-McAdams, MW (Master of Wine), is a New York based wine educator, freelance writer and consultant.