Air and Water Processes Do Not Produce the Same High-Quality Pasteurization of Donor Human Milk

Background: Holder pasteurization is the most commonly used technique in milk banks worldwide, but higher temperatures and longer pasteurization time have been associated with damage to the immune components of human milk. Research aim: This study aimed to assess the detailed pattern of pasteurization temperature using two water pasteurizers (WP1 and WP2) and one air pasteurizer (AP). Methods: The milk temperature during each phase of the pasteurization cycle was recorded using 6 to 9 probes, depending on the number of bottles, in the pasteurizers. We used 90 to 200 ml bottles to assess the effect of volume on milk temperature. Results: The time to heat the milk from room temperature to 58 degrees C was 12.4, 12.9, and 64.5 min, respectively, for WP1, WP2, and the AP (p <.0001). The duration of the plateau was 35.5, 35.2, and 45.8 min (p <.0001). The duration of exposure to a temperature above 58 degrees C was 49.6, 40.7, and 76.2 min (p <.0001). The total duration of a full cycle was 79, 66, and 182 min (p <.0001). The duration of exposure above 58 degrees C for the different volumes of milk treated showed no difference when using WP1 but was significantly longer in small volumes when using WP2. Conclusion: Human milk treated using the air pasteurizer in our study was exposed to higher temperatures and for longer periods of time than the water pasteurizers we employed. Regular qualification of pasteurizers is requested when evaluating the effect of pasteurization on milk components and for routine treatment of human milk in milk banks.