In a recent answer, you mentioned "a fill level (also known as 'ullage') that is consistent with a wine of its age." How does that work?
Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.
Dear Dr. Vinny,
In a recent answer, you mentioned "a fill level (also known as 'ullage') that is consistent with a wine of its age." How does that work?
—Halston B., Los Angeles
Dear Halston,
Ullage (pronounced "UH-lij") actually refers to the amount of wine "missing" from a bottle—the airspace between the bottom of the cork and the top of the wine's fill level. The older the bottle, the greater this distance becomes. The (very slow) loss of wine by evaporation is to be expected; loss by leakage is a problem.
A 10- to 15-year-old wine should still have a fill level into the bottle's neck, whereas a 40-year-old wine may have a level below the neck, in what's called the "shoulder" of the bottle. But beware the ullage! The greater the gap, the greater the risk of spoilage. So, if the fill level is down to a "low shoulder" or below, it may be considered too poor of a level for a wine of any age.
There's another rule of thumb that some collectors espouse: Avoid bottles with more than half an inch of ullage per decade of age. This rule is especially useful when evaluating Burgundy bottles, which have more of a "slope" than a "shoulder." Also, be suspicious of bottles where the fill levels seem inappropriately high for their age—they may have been topped off, most likely with a younger vintage.
—Dr. Vinny
