Mothers milk cannot be duplicated because, in reality, no two mothers produce identical milk. Even the milk of an
individual mother varies from day to day and during different times of the day - just as other fluids and systems in
our bodies fluctuate.
(Harzer,G: Changing patterns of human milk lipids in the course of lactation and during the day. AM J Clin Nutr 1983; 37:612-21.)