the.com/ullage
the empty space wine leaves behind, measured like a confession of what's missing
means The amount by which a container, especially of wine or other liquid, falls short of being full — the empty space at the top.
from From the Old French 'ouillage' or 'eullage,' meaning the act of filling up a cask, which came from the verb 'ouiller' — to fill a barrel to the bunghole. That verb is thought to derive from 'œil' (eye), the French word also used for the bung-hole of a cask, which resembled an eye. So 'ullage,' oddly, began life as a word about topping up, and slid over time to name the very gap that topping-up was meant to cure.
- barrel breath
- Evaporation through wood is called the angel's share
- fill it up
- Topping off the gap prevents oxidation and spoilage
- rocket fuel
- Spacecraft tanks need ullage settling before engines fire
- old roots
- Comes from Latin oculus, the eye, meaning the bunghole
- auction tell
- High ullage signals an old bottle may be ruined
wine barrel evaporation loss — approximately 2-3% of wine volume lost per year through the cork in barrel aging, called 'the angel's share'