Only the raw fish items are marked as food, nothing else. It makes this mod have strange compatibility with extra utilities, since the culinary generator can not "eat" all the food from this mod.

There is no such thing as 'marking as food'. I would have to extend ItemFood. I'm using my own implementation. It's on ExU to have a way around this/register stuff as foods. Which it doesn't.

I was there first.
rwtema/extrautilities_old_issues#237

Then you're SOL.