Good question. Sunshine polishes off the cookie and brushes crumbs off of her hands... hands which make for inefficient holders of liquid. There's a certain amount of water in a flower, she supposes - does that count for anything?

"Barring the amount of water inherent in a flower or a blade of grass," no, "I don't know. I've never tried."

Maybe because in order to test whether you'd been successful, you'd probably want to transmute one drinkable thing into another drinkable thing, and that would require a taste test to see if it had worked. So much for changing it back after it's been swallowed. Also, while 'never ingest something you've transmuted' isn't an official rule her grandmother taught her, it seems like common sense.