The rationale of adding an acid to cow's milk to improve its digestibility has been demonstrated by Clark1 and Faber2 and popularized recently by Marriott.3 They show that the buffer value of cow's milk is considerably more than that of human milk. Therefore the former milk neutralizes a larger amount of the hydrochloric acid of the stomach. The resultant effect is an interference with the activity of the gastric enzymes through a reduction of the gastric acidity below the optimal hydrogen-ion concentration zone of pH 3.5 to 5.0. By the addition of an acid to cow's milk its excess buffer salts may be counteracted, and its digestibility made to simulate more nearly that of human milk. This method does not entail any appreciable reduction of the food elements, as pertains to the ordinary method of simple dilution.
The question as to what degree of acidification of