Disgorgement is the process that ejects the sediment under the force of the pressure in the bottle. First the bottle must be opened, turning it upright in the process.
This can be done in one of two ways:
It remains for him to check the clarity of the wine, using his nose to check for the smallest abnormal aroma, then blocking the neck with the thumb of the left hand as he places the bottle on the dosage machine.
A firm hand and considerable experience are essential to maintain an average rate of 400 bottles disgorged per day. If the bottle is turned upwards too soon, the sediment will mix back into the wine and make it unfit to drink. If on the other hand the bottle is not angled correctly, a large quantity of wine will be lost.
Modern disgorging units increase the rate of uncapping 20-fold, while also taking the load off the cellar workers.
Something astonishing happens as the bottles are opened: there is no escape of gas – barely a trace of mousse. Low temperature has something to do with it, as does the carbon dioxide supersaturation that occurs in the course of second fermentation. Mainly though, this is thanks to extremely delicate handling, being careful not to knock the sides of the bottle. The slightest bump will cause an explosion of the imprisoned carbon dioxide, sending the contents gushing out like a hydrant.
The rate of disgorgement ranges from 2000 to 18,000 bottles per hour, depending on the level of mechanisation and automation. Modern disgorging facilities normally include: