What a faff those rules are. Even customs officers don't get them right. I got asked one time by customs if I was "sure I didn't have any food I was bringing in. I'd ticked no on the form. "No," I said. "Just some tea for my family." "That's food. You have to declare it."
OK, fine. Next time I ticked yes.
"What food do you have?" "Some tea." "That isn't food. Don't tick the box unless you have fresh produce, meat, cheese, that kind of thing. You should know that."