French to English Other Cosmetics, Beauty Perfume

OK - I give in, I've been going round and round with this one and obviously not looking in the right place. I thought I had it with fragrance chemist but it's not at all the same job. It's the person who is responsible for the manufacturing process not the "creation"of a perfume. I don't think I can go with "assistant" as in "préparateur en pharmacie". Anyone out there have any experience in the field?

Le préparateur, ou cuviste, est la personne qui gère la fabrication d’un parfum.... Après avoir contrôlé les matières premières, il se charge de fabriquer le jus.

And the article goes all the way to the point at which the product is ready for packaging. So a serious job with responsibility.

Many thanks for your help and time.