02/11/2025
In the last NLCA Newsletter we mentioned that the type of freezer used to freeze and store expressed breastmilk may contribute to the off odor and taste sometimes occurring in frozen breastmilk. New research suggests that the changes in smell and taste are not necessarily caused by high lipase levels in the milk but instead are about freezer temperatures causing damage to the membrane surrounding the milk fat globule. The crystallization of milk lipids that occurs during freezing can damage this membrane, allowing lipases access to lipids, and subsequently breaking down the lipids that result in the off odor and taste. The researchers found that milk samples with the rancid smell were not generally higher in lipase than those that didn't change in smell. The research team is investigating the use of safe natural additives (vitamin C and pectin) that would protect human milk from such freezer damage.
Silpe, J.E., Damian-Medina, K., & Bassler, B.L. (2025). Food-derived compounds extend the shelf-life of frozen human milk. bioRxiv [Preprint]. Jan 12, 2024.12.11.627965.
Breastmilk is known to provide optimal nutrition for infant growth and development. A cross-sectional analysis of nationally representative US data from 2016 to 2021 revealed that >90% of lactating mothers reported using breast pumps to express milk.[1][1] We conducted a survey of n = 1,049 lactatin...
