Riddling is an operation which aims to carry sediments formed after the second fermentation to the neck of the bottle. In the past, riddling was performed manually: bottles were placed on wooden racks called "pupitres" with the crown cap pointed down.  Once a day during three weeks the bottles were given a quarter turn to the right with the angle gradually increased until the position of bottles is almost straight down. Nowadays, this process is mechanized with riddling equipment, a modern version of "turnover" invented by Patrice Monmousseau 30 years ago.