Buffer Intensities of Milk and Milk Constituents

Titration data on milk have been published by Van Slyke and Baker (l), Buchanan and Peterson (2), Moser (3), and others. Titration curves of milk have been given by Clark (4) and by Moser (3). Buchanan and Peterson (2) have calculated the buffer efficiency of milk for a number of zones of the pH range. Clark (4, 5) has made several similar calculations and has outlined the difficulties to be avoided or surmounted in integrating the buffer activities of the components of milk. It has not been feasible to use any of these data in this work because of the possible differences in composition in the milks employed and because of the non-uniformity of range and frequency in the data reported. Wherever comparisons were possible, the agreement between previous data and those of this paper was satisfactory. Themathematicaltheoryof bufferactioninheterogeneoussystems has been developed by Kugelmass (6) and by Klinke (7). While these methods of calculation cannot be applied to hydrogen ion buffering in systems mvolving casein until the essential constants are known with a fair degree of accuracy, it appears from the general aspect of Klinke’s calculations that the effect of phase buffering should be most intense at the hydrogen ion concentra-