Absolutely, I find food gunge much more exciting than ordinary slime. Love all the substances you've mentioned, and would add things like gravy and mushy peas. In fact pretty much any food, though I would draw the line at spicy foods (don't really want certain body parts to feel like they have caught fire..!).
Would love a bath tub full but sadly not an easy thing to achieve - and I've often wondered how you get rid of it all afterwards...
Clothes-wise I like sports kit best and trackies are great for filling up. And other shiny materials like pvc and rubber are interesting...