How to: Storing Milk

Storing Pumped Milk for Donation

Proper storage of your pumped breast milk is important in keeping your breast milk safe for donation.

  • MMBA can accept milk in any sterile milk storage bags, or food-grade hard plastic or glass containers which have been boiled for five minutes.  We prefer going forward that you freeze milk in the sterile containers MMBA provides to reduce waste that results from torn milk storage bags, and to reduce the loss of fat. Both MMBA and all milk depots have containers available for you once you are in the screening process. Need more milk storage containers? Let us know.
  • Leave ½ inch at the top of the container for the milk to expand as it freezes.
  • Refrigerate or freeze your milk within 30 minutes of pumping. You may refrigerate your milk for up to 24 hours before freezing.
  • Store milk in your freezer until you are ready to drop off the next deposit. Typically, you may store your milk for three to four months in a freezer, or up to seven months in a deep freeze before delivering it to MMBA. If you have questions about your frozen milk, call us.
  • Let us know if freezer space is a problem for you – we can help with delivery and storage arrangements.
  • Check freezer temperature regularly in case of power outages or door being left open.

In case of emergency: Power Outage/Storm

When storms and the threat of loss of power are in the news, it always raises questions about what to do about stored milk if the power goes out. Moving milk to the freezer from the refrigerator is the first step to take. If you are a milk donor, taking milk to the nearest depot before the storm is also very wise.

Freezers will keep milk and other items frozen for 12 to 24 hours without intervention as long as no one is opening and shutting the door. If power is out for longer periods, dry ice added to the freezer every 12 hours (amount differs by size of freezer) will keep foods frozen. If there is no dry ice available, keep the freezer closed until the power is back on, and then evaluate your milk supply very carefully.

According to the Centers for Disease Control and Prevention, your milk is still fine if it has ice crystals in the container. If it doesn’t have ice crystals (you can’t hear little sounds when you shake the container) then the milk is thawed and must be kept chilled and fed to your baby without refreezing, ideally within 24 to 48 hours.

Electric pumps without battery chargers are a challenge when the power is out, but manual expression of milk is still feasible, and of course, breastfeeding should be uninterrupted.

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