Pasteurization efficiency of donor human milk processed by microwave heating

Abstract

The main objective of this work was to verify the efficiency of batch microwave-assisted heating for donor human milk and assess the activity of alkaline phosphatase (ALP) and microbiological quality. Processing was conducted at different temperatures between (50 and 80) degrees C and times from (5-300) s in order to evaluate the suitability of ALP as a target for the microwave process of donor human milk. The thermal inactivation of ALP followed first-order kinetics with a z-value of 4.4 degrees C that indicates a strong dependency of ALP inactivation with temperature. The optimal conditions (60 degrees C for 30 s) were determined, based on ALP inactivation, and the microbiological quality of the processed donor human milk was evaluated. No pathogens (mesophilic bacteria, coliforms at 35 degrees C, Salmonella spp. and Staphylococcus spp.) were detected after microwave-assisted heating and this suggests that this technology can be applied to ensure adequate safety and quality in Human Milk Banks (HMBs).