Is it 4 hours or longer? We are traveling on a 2 hour trip to visit family so I'm going to pump him bottles for the road. Do newborns not like it if its not as warm as from the tit? Can I refrigerate it then warm it back up?
If you wanted to warm it up, you can either get a bottle travel warmer, carry along a regular bottle warmer and plug it up at rest areas or restaurants with access to a plug, or you could go into the gas station with the bottle and get a coffee cup and pour hot water into it and put the bottle in that for a few minutes to nuke it. I've done all three. Depends on who you are traveling with and how much time you are willing to take to warm it up.