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Storage of Unfed and Leftover Pasteurized Human Milk
Ting Meng1, Maryanne T Perrin1, Jonathan C Allen1
11 Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University , Raleigh, North Carolina.
Summary
Refrigerated pasteurized human milk, including leftover milk, remains safe for 7 days. Room temperature storage for pasteurized milk increases bacteria and decreases immune factors within 12 hours.
Area of Science:
- Human milk research
- Microbiology
- Immunology
Background:
- Pasteurized human milk is a vital nutrient source for infants.
- Understanding the impact of storage conditions on milk safety and immunological properties is crucial.
Purpose of the Study:
- To assess bacterial growth and immunological activity in pasteurized human milk and leftover milk after storage at different temperatures.
- To determine safe storage durations for pasteurized human milk.
Main Methods:
- Human milk samples were pasteurized and then stored at room (24°C) and refrigerated (4°C) temperatures.
- Analysis included bacterial counts, total protein, lysozyme activity, and secretory immunoglobulin A (SIgA) levels.
- Samples were evaluated after storage for up to 7 days.
Main Results:
- Refrigerated storage (4°C) for 7 days showed no significant increase in bacteria and stable protein content in both pasteurized and leftover milk.
- Room temperature storage (24°C) led to a significant increase in bacteria in leftover milk within 12 hours.
- Room temperature storage also caused a significant decrease in total protein and SIgA in pasteurized milk within 12 hours.
Conclusions:
- Pasteurized human milk and leftover pasteurized milk can be safely refrigerated for at least 7 days.
- Storage of pasteurized human milk at room temperature requires caution due to increased bacterial growth and reduced immunological factors.
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