I kept mine in those double sealed bags for storing milk for a year. I had read somewhere that is the longest you should keep it after the date pumped. It needs a good shaking after thaw, but other than that it was fine. I did this with both my sons. I weaned with it, I added it to cereal, I mixed it with cow milk etc.... for extra nutrients as they stopped breastfeeding. I would look on websites like la leche to see.