I'm so sad! I expressed a 5oz bottle of breast milk on Thursday and put it all the way in the back of my fridge. Today is a Sunday and I smelled it and it smelled perfectly fine, but when I tasted it, omg it was AWFUL! It definitely has gone bad even though it smells perfectly fine. I usually never taste my bm before giving it to her but I'm so glad I did this time. And I know I have given her 3 day old milk before too. It might of been bad all those other times and I didn't know it (because I relied on the sniff test). Now I'm sad I have to toss out a full 5oz bottle! When does your milk go bad? Do you do the sniff and/or taste test?