I know that technically this probably isn't the right thing to do but I do what you do....pump into the bottles, put them in the fridge, and then pump back into the same bottles. I figure the amount of milk I am getting is so small (only 1 1/2 oz per day right now) that it will cool very quickly in the refrigerator that bacteria won't have time to grow. I also figure if it's ok to leave fresh milk out for 10 hours it shouldn't be a big deal, as long as you're only pumping into the same bottles for a single day. I just make sure I put it back in right after pumping.