How Long Is Thawed Breast Milk Good For?
Tips for Safely Using Frozen Breast Milk
Freezing breast milk extends the storage time. Once you thaw the frozen milk, it's best to use it quickly to feed your little one safely.
When you head back to work, having a stockpile of expressed milk makes you feel better about the food your little one gets while you two are apart. But filling your freezer with the pumped milk also comes with questions about proper handling and thawing. Brush up on breast milk storage recommendations to ensure your little one gets the safest meals possible.
How Long Can You Use Thawed Breast Milk?
Once you thaw breast milk completely, it's best to use it as soon as possible. Experts suggest using the milk within 24 hours of it thawing fully. Thawed breast milk should not stay out at room temperature for more than two hours because it loses its ability to stop bacterial growth. Keep the thawed breast milk in the refrigerator until you're ready to feed your baby to minimize the risk of bacteria growing.
Experts recommend throwing out thawed breast milk that doesn't get used instead of refreezing it. There isn't much research on refreezing previously frozen and thawed breast milk, so it's tough to say how safe breast milk is after refreezing. Thawing only what you need for the next 24 hour cuts down on wasted milk.
Proper Breast Milk Storage
Breast milk naturally resists bacterial growth, but that resistance to bacteria starts to diminish the longer you store it. Freshly pumped breast milk can stay at room temperature for up to six hours if the room isn't too hot. In the refrigerator, the optimal storage time is up to four days, but it can last five to eight days if you keep it in a clean area.
Freezing breast milk is the only safe option for long-term storage. You can store the milk in a freezer for up to six months safely. In a separate deep-freeze unit, the milk lasts up to 12 months, although using it within six months is ideal.
Changes start to happen to breast milk after three months in the freezer. It starts to lose fat, protein and calories, so it doesn't offer as much nutritional value as fresh milk. Acidity increases after about three months. Vitamin C levels start decreasing anywhere from one to five months after freezing.
The best spot for milk is the back of the freezer where it isn't affected by warm air each time you open the door. If you have a self-defrosting freezer, keep the milk away from the freezer walls. Store the frozen breast milk in tightly sealed containers labeled with the date.
Thawing and Heating Frozen Breast Milk
Ready to use your frozen breast milk? Start with the oldest milk, so you use it up before it goes bad. The safest and easiest way to thaw the milk is to move it from the freezer to the fridge. Keeping it in the fridge minimizes the chances of bacteria growing in the milk as it thaws. This method also minimizes fat loss from the milk. Get into the habit of moving breast milk from the freezer to the fridge at night, so it's thawed and ready the following day.
Thawing in a pinch. Sometimes you might forget to transfer the frozen milk to the fridge. Or you suddenly realize you don't have any thawed milk when you need it. An alternative for faster thawing is running warm water over the bottle or storage bag. You can also put the container into a bowl of warm water.
Never thaw or heat breast milk in the microwave. Not only does it heat unevenly with the potential for dangerous hot spots, but it can also mess up the antibodies in the milk. Heating bottles in a pan of hot water on the stove can also break down the nutrients in the milk, including decreasing the fat content. Gentle heating is best to keep as much of the nutritional value of the milk as possible.
Serving temperature. You can serve the thawed breast milk at any temperature. It's perfectly fine for your baby right out of the fridge. But if your little one prefers a little warmth, use the warm water trick to heat it up. Let the thawed milk sit in a bowl of warm water until it reaches a temperature your baby likes. Swirl the milk gently to help it warm evenly. You can also use a bottle warmer to safely heat the thawed breast milk.
- Mayo Clinic: Breast Milk Storage Do's and Don'ts
- Kelly Mom: Breastmilk Storage and Handling
- Academy of Breastfeeding Medicine: ABM Clinical Protocol #8: Human Milk Storage Information for Home Use for Full-Term Infants
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