Breastmilk can be frozen (in a sterilized bottle). If special containers for this purpose aren’t used, you can express into a normal (sterilized) bottle, covering it with plastic or foil to prevent contamination.
How to thaw : swirl bottle with frozen expressed breast milk under running, warm water. Don’t thaw at room temperature : it takes too long, spoiling may occur.
Never heat in a microwave.
Never refreeze once thawed.
How long can expressed breast milk be stored? Fridge ice compartment 2 weeks; freezer 3 months.