What do you call a person who collects recipes, ingredients or other cooking related materials?
While several terms loosely fit the criteria (such as a culinarian), a culinophile or reagenteur speaks more to my tastes (if you don't mind portmanteaux).
As for what one might call the group, taxonomy or classification are appropriate when ascribing the term to a family derived from a particular set of criteria. Plenty of additional terms are available in online Thesauri, if you're curious.
"Foodie" (although that suggests someone interested in preparing and eating the food too).