Ha! ;-) I don't wash milk; if it smells bad, the whole bottle goes down the drain. But everything that's solid is washable, esp. cheese, meat, etc.

And indeed, keeping rice for too long is really not recommended.

(I don't know why you're downvoted).

I guess they mean "wash the neck of the bottle". The neck can gather milk that goes off and smells even if the rest of the milk is ok.

Luke warm water for 45 seconds