You may be confused by the many guidelines
that there are for how long milk can be safely stored. I see red
every time I read one of the "helpful" breastfeeding guides
distributed by the formula companies that say things like
"breastmilk can be stored for 24 hours, if breastmilk is left at
room temperature you need to throw it out". Of course their
guidelines are short - the more breastmilk you throw away, the
more formula they sell. The following guidelines are from
La Leche League, an organization that pioneered
breastfeeding advocacy when there was no such thing. These
guidelines are based, as much as possible, on laboratory
research testing breastmilk at different time-points for
Storing milk in 2-4 ounce amounts may
reduce waste. Refrigerated milk has more anti-infective
properties than frozen milk. Cool milk in the refrigerator before
adding to frozen milk to prevent thawing.
Is my milk spoiled? Sometimes
milk that has been stored develops a soapy or metallic taste.
This does not mean the milk is spoiled. It is because the
enzymes that help digest breastmilk can sometimes break down
some of the fats, resulting in what adults taste as an "off"
flavor. If your baby drinks the milk, you don't need to do
anything different. If your baby refuses this milk,
the milk before you store it will stop the activity of these
Breastmilk that is actually spoiled is pretty unmistakable - it
will smell positively foul. Don't worry, you'll know.
can be stored:
- at room temperature (66-72░F,
19-22░C) for up to 10 hours
- in a refrigerator (32-39░F, 0-4░C)
for up to 8 days
Store in the back of the refrigerator, not in the door.
- in a freezer compartment inside a
refrigerator (variable temperature due to the door opening
frequently) for up to 2 weeks
- in a freezer compartment with a
separate door (variable temperature due to the door opening
frequently) for up to 3 to 4 months.
- in a separate deep freeze (0░F,
-19░C) for up to 6 months or longer.
- Talk to your doctor about more
conservative storage guidelines if your baby is premature,
immune compromised, or seriously ill.
Containers: Refrigerated or frozen milk may be stored
- Hard-sided plastic or glass
containers with well-fitting tops
- Freezer milk bags that are
designed for storing human milk
- Disposable bottle liners are not
recommended, unless they are specifically designed for
- Thaw and/or heat under warm,
- Do not bring temperature of milk
to boiling point.
- Gently swirl milk before testing
the temperature. Swirling will also redistribute the cream
into the milk. (It is normal for stored milk to separate
into a cream and milk layer.)
- Do not use a microwave oven to
heat human milk. Microwaving kills many of the living immune
cells that fight disease. Microwaving any beverage can also
create hot spots that can burn your baby's mouth.
Can you re-use a previously heated
bottle of breastmilk? I think you can, but check
here to see the evidence.
Thawed (previously frozen) Milk
If milk has been frozen and thawed, it can be refrigerated for
up to 24 hours for later use. It should not be refrozen. It is
not known whether milk that is left in the bottle after a
feeding can be safely kept until the next feeding or if it
should be discarded.
According to THE BREASTFEEDING ANSWER
BOOK, page 228, research indicates that human milk has
previously unrecognized properties that protect it from
bacterial contamination. One study, Barger and Bull 1987, found
that there was no statistically significant difference between
the bacterial levels of milk stored for 10 hours at room
temperature and milk that had been refrigerated for 10 hours.
Another study, Pardou 1994, found that after 8 days of
refrigeration some of the milk actually had lower bacterial
levels than it did on the day it was expressed.
Expressed milk can be kept in a common
refrigerator at the workplace or in a day care center. The US
Centers for Disease Control and the US Occupational Safety and
Health Administration agree that human milk is not among the
body fluids that require special handling or storage in a