The Effect of Processing Donor Milk on Its Nutrient and Energy Content

The pasteurization is a mandatory step to inactivate pathogenic microorganisms of bank milk. For storage, freezing and thawing are necessary. The concentration of macronutrients and energy of bank milk could be influenced by these procedures which are routinely used in human milk bank. The aim of this study is to analyze the effect of bank milk processing (pasteurization and freezing/thawing) on the macronutrients (fat, protein, and carbohydrate) concentration and energy content. The samples of donor milk were collected and studied before/after pasteurization and after frozen for 3 months. Total 100 samples of bank milk were tested using an infrared analyzer. The measurements of fat, protein, carbohydrate, and energy were statistically analyzed by SPSS. There was a prominent reduction of fat mean concentration following pasteurization and frozen (20.5% and 6.5%, respectively). The processing did not cause significant changes in protein content, but there were significant increase after pasteurization and decrease after frozen in carbohydrate (p < 0.05). Overall (postpasteurization and frozen storage), a 9.6% decrease was observed for energy content. This study revealed that the processing of bank milk (including Holder Pasteurization and frozen storage) decreased fat and energy content of human milk significantly, and this could not meet the specific needs of preterm infants.