fatty acid

Hi, I've been working on formulating soap recipes using fatty acid profiles. My question is can you look at a recipe and tell if it will trace really fast? That would be more to do with the oils wouldn't it? What makes an oil trace quickly, does it come back to it's fatty acid profile? Or is...

I thought about adding some certain foods to some soaps and figured that knowing the fatty acid composition would help determine what oils to use. I'm wondering how to determine how this will effect the oils & soap