The reduced sulfur balances of growing infants reported in an earlier paper1 impelled us to make a third long term study of the metabolism of a normal infant, fed breast milk for the first 8 test periods and cow's milk for the remaining 6.
Efforts were made to reduce all possible chances of error in the determinations of sulfur. The open-dish method of oxidation of Benedict2 and Denis,3 used for the determination of sulfur in urine, stool and dried milk, was modified according to the suggestion of Waelsch and Klepetar:4 The oxidizing medium was made alkaline to approximately pH 7.2 by the addition of a saturated solution of sodium carbonate. Sulfur was determined subsequently as barium sulfate. Average values of 10.4 mg of sulfur per hundred cubic centimeters for breast milk and 0.204 per cent sulfur for powdered whole cow's milk were obtained; these correspond
IOB V, SWANSON WW. SULFUR METABOLISM OF EARLY INFANCY. Am J Dis Child. 1939;58(1):37–40. doi:10.1001/archpedi.1939.01990070049004