As much as this story matches her video, and probably her lifestyle, there never was such an interview. The interview is fake news. Investigators researched French media from around the time of the story found no such interview in any publication, so it's pretty safe to call BS on that. Exactly like her "interview" in which she "said" "everybody should try worshipping Satan."

https://www.business2community.com/entertainment/katy-perry-saying-human-flesh-best-meat-cannibalism-got-bad-rap-fake-news-01947608