Omg yes this was my issue ! My baby refused to take frozen BM. The only way he would take it was if it was frozen for less than a month cause the strong taste isn’t much then. The longer the milk is in the freezer the stronger the taste is/gets. So that’s one reason I stop pumping cause the milk would just end up wasted 🥹. I was so upset cause the first milk I pumped had colostrum in it. And he refused so I had to get ride of it. Sometimes I added it to his bath .
I have this problem too
You might have high lipase which causes the milk to have a different taste after thawing. You can google some solutions I’ve heard scalding it before freezing helps but I’ve never done it. Adding alcohol free vanilla could help.