What is the fine-grained topic of the following text: Different people (and by people I mean the foodies whose palates are a bit more discerning than mine) see less differences between crème fraiche, sour cream, and Mexican crema than I do; this foodie-inspired site has a discussion thread asking about the relative differences between the three creams. Only return the topic.
Differences between crème fraiche, sour cream, and Mexican crema.