Ultrasound Technology as a Method for Homogenizing Human Milk

Abstract

ABSTRACT Background: The lipid content of human milk is its most variable component and provides from 35 to 50% of the daily energy needs of newborns. Losses occur during the freezing and thawing processes due to the coalescence of the fat globules and their adherence to bottle walls. Objectives: The objective was to test two methods of homogenizing pasteurized human milk in human milk banks in order to reduce the nutritional losses that occur between storage and feeding to newborns. Methods: Human milk samples collected in duplicate were homogenized either by sonication (MIRIS, Sweden) or vortex tube agitation. A total of 941 milk samples of different lactation stages from the human milk bank in Blumenau (SC, Brazil) were analyzed. A human milk analyzer (MIRIS, Sweden) was used to determine lipid content after homogenization. The statistical significance adopted in this study was á = 5%. Results: A mean of 1.87 grams of lipids per deciliter (g/dL) was observed in vortex-homogenized milk, whereas ultrasound homogenization yielded a mean of 2.07 g/dL, p < 0.01. The mean energy value of vortexhomogenized milk was 33.36 Kcal/dL, compared to 35.81 Kcal/dL for ultrasound-homogenized milk, p < 0.01. Conclusion: This study demonstrates that there is energy loss when human milk is not properly homogenized before being fed to newborns; better homogenization techniques decrease the adherence of fat globules to the bottle walls.