Using a clever but painstaking method, Amandine deduced who was really supplying the Champagne to the supermarkets, and she found out it was not the usual suspects.
Then Amandine asked them which houses supplied Champagne for supermarket brands (a practice many in the industry thoroughly detest, but it is very difficult to observe who is hiding behind those supermarket labels).
For example, in an intriguing research project with my (rather exceptional) PhD student Amandine Ody, we asked lots of people in the Champagne industry whether different Champagne houses paid different prices for a kilogram of their raw material: grapes.