Macronutrient content of pasteurised donor human milk: Variability between batches from single-donor pools at an...

This study aimed to characterise the between-batch variability of pasteurised donor human milk (PDHM) produced from single-donor pools at Australian Red Cross Lifeblood's milk bank and identify key donor characteristics that predict macronutrient content.

Macronutrient content from 200 batches of PDHM was measured using a mid-infrared human milk analyser (Miris, Uppsala, Sweden). Linear mixed models were used to study the impact of stage of lactation and gestational age on macronutrient content. Coefficients of determination (R² ) were calculated to estimate the impact of the individual donor on overall variability.

Macronutrient content of PDHM varied considerably, with between-batch variations of 2.8 and 6.4-fold for protein and fat content, respectively. Mean crude protein content was 1.16 g/100 mL, ranging from 0.7 to 1.96 g/100 mL. Mean fat content was 3.85 g/100 mL, ranging from 1.46 to 9.39 g/100 mL. Stage of lactation was identified as a predictor for protein content and gestational age at birth for fat content. Individual donor effect explained 55 and 35% of the variance for fat and protein content, respectively.

This study highlights the variation in macronutrient content in PDHM at an Australian milk bank. Variability could be reduced through the implementation of targeted multiple-donor pooling using the key donor characteristics identified in this study along with the measurement of macronutrient content of individual donors at the time of first donation. However, the clinical benefit of a reduction in between-batch variation, achieved through multiple-donor pooling, would need to be assessed to justify additional efforts associated with PDHM processing changes.