I mean, they probably could taste energon and stuff. But can they taste human food?

Like what would they think of it, if they could.

Unlikely. Logically speaking, robots don’t have sensory like we do. They can see. But they can’t do much else. As for food, it would not make it past their speech emitter, or mouth. Simply put it, they would say it taste like nothing.

It's been implied that cybertronians have access to our five basic senses, plus maybe some of their own. They just operate in a different way than ours. I don't know if they would care for human food in their base form as it's probably adapted to very different stuff. If they had an organic alt-mode they might find they like it or find the experience very disgusting. Just depends.