How come when Hiro stops the time, liquid is also stopped (for example stops in mid-pour) but when Hiro feeds Matt Parkman Jr. in 3x20, the sữa in the bottle is still liquid?

I haven't seen the episode yet because I am in Australia but I assume like how people touch hiro when he stops time, they can di chuyển then wouldn't that would apply the same to the sữa bottle in 3x20? So probs if he didn't touch the bottle mid-pouring then it would freeze.

Well when hiro freezes time if he's touching something it doesn't freeze like baby matt didn't and like when hiro was touching ando he froze time and ando didn't freeze so when hiro was holding baby matt he didn't freeze nor did the milk.