Food-Derived Compounds Extend the Shelf Life of Frozen Human Milk

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. We conducted a survey of n = 1049 lactating or recently lactating individuals from a US nationally representative population to explore breastmilk storage practices among this group. The data revealed that 83% of respondents store breastmilk in their homes, with 68% using freezers to do so for >1 month. The lowest available temperature in most household freezers is −20 °C, a temperature that is inadequate to maintain human milk’s emulsified structure, leading to separation, degradation of fats, loss of key vitamins, and changes in palatability. We developed a first-of-its-kind high-throughput screening platform to identify food-derived compounds and combinations of compounds that, when added to human breastmilk, preserve fat content, retain antioxidant capacity, and reduce production of rancid-associated free fatty acids during extended freezer storage. Our screening identified pectin (0.5% w/v) and ascorbic acid (100 μg/mL) as optimal preservation agents. Compared to untreated controls, this formulation reduced glycerol production by approximately 60% and maintained antioxidant capacity after 6 months of storage at −20 °C. Lysozyme and protease activity were maintained at >75% of the levels in fresh breastmilk. This formulation represents a lead for the development of safe and affordable frozen breastmilk shelf-life extenders for at-home use to increase the longevity of stored breastmilk.