Hi K.,
Congratulations on working to provide your daughter the best start in life.
I was concerned that I had excess lipase when my son refused a bottle, also. I smelled and tasted my milk, and the stored stuff had a distinctly different taste and smell than freshly expressed. However, after speaking with the head of the milk bank (I was concerned about the milk I was donating), she assured me that excess lipase is VERY rare and that every mother's milk tastes differently after being expressed. Apparently the milk composition begins changing immediately after being expressed. There are a couple other reasons your daughter may be refusing the bottle.
* Is someone besides you giving your daughter the bottle? I know my son would absolutely refuse a bottle if I were anywhere in the vicinity.
* Have you tried giving your daughter the bottle at the same time of day, with the same caregiver, on numerous occasions? If it takes up to 18 introductions of a solid food before a child likes it, it could be the same for the bottle for some kids.
Another thought to keep in mind: Some babies, like mine, will moderate their daytime feedings and wait until you are around to make up for calories and time with you. My son chose to wait until I got home, then ate voraciously and frequently.
I sincerely hope that one of these other suggestions is the key to your dilemma as you are already going to be pumping, which will be enough of a challenge.
Please call your local La Leche League leader (www.llli.org) and attend a meeting. The support and answers to questions like this is invaluable.
Good luck!