As you may have seen by now, recommended storage times for expressed breast milk (EBM) in the freezer and in the fridge can vary quite a bit, depending on which guidelines you look at and factors like the type of freezer used. For freshly pumped breast milk, the UK and US government guidelines are generally the same, which is that EBM can be stored in the back of the fridge for up to 5 days at a temperature of 4o C (39o F) or lower.
There is a study, cited in the American Academy of Pediatrics (AAP) 2012 position statement on Breastfeeding and the Use of Human Milk, which looked at the changes in expressed breast milk stored in a refrigerator in a hospital setting. Many factors were measured over time, including the pH, bacterial count, protein level and white blood cell counts. It found that EBM could be kept in a fridge for up to 96 hours (4 days) with minimal changes to its integrity. That’s good news. But, should expressed breast milk really be kept this long in the fridge? What about its taste?
What I have found over the months, is that the length of time the fresh breast milk sits in the fridge also impacts its taste. Very fresh breast milk tastes really good! It has a mild sweet aftertaste but is essentially quite bland. Think of 1% or non-fat cow’s milk but with a lighter, more watery and slightly sweet taste. By day 2, the expressed breast milk is already starting to taste a little ‘off’; you can taste a tiny bit of the free fatty acids from the lipases working, and a whitish layer forming on the top of the milk. By day 3, the ‘off’ soapy bitter taste is even stronger, even after mixing in the fat layer to the rest of the milk. I think at this point the baby may not be as willing to accept the milk already. If this is the case, you could try warming the milk more before offering it to baby, or use it in baby’s solids instead. By day 4, the ‘off’ taste gets even stronger. Much stronger.
The take home message? I would recommend using your expressed breast milk within 24 hours if kept in the fridge to optimize its taste and acceptability to the baby. Otherwise, definitely use it up by 4 days (96 hours). And still keep it at the back of the fridge! If you don’t think you’ll use it within 24 hours, then it may be best to freeze it, and then when you need it thaw the expressed breast milk and use it as soon as you can after it is thawed!
1. Centers for Disease Control (CDC). Proper handling and storage of human milk. http://www.cdc.gov/breastfeeding/recommendations/handling_breastmilk.htm. Accessed 26 October 2013.
2. National Health Service (NHS). Expressing and storing breast milk. http://www.nhs.uk/conditions/pregnancy-and-baby/pages/expressing-storing-breast-milk.aspx#close. Accessed 26 October 2013.
3.Section on Breastfeeding. American Academy of Pediatrics. Breastfeeding and the use of human milk. J Pediatr 2012;129: 3: e827-e841. http://pediatrics.aappublications.org/content/129/3/e827.full.pdf+html. Accessed 26 October, 2013.
4. Slutzah M, Codipilly CN, Potak D, Clark RM, Schanler RJ. Refrigerator storage of expressed human milk in the neonatal intensive care unit. J Pediatr. 2010;156(1):26–28.