In the present study, pH-stat methodwas calibrated by TNBS and OPAreactions for control of hydrolysis of corn gluten
by Alcalase. Hydrolysis experiments were conducted in a batch reactor at the temperature of 50 ◦C for various pH
values, and at pH 7 for 40 and 60 ◦C. The calibration was characterized by good linear correlations for both methods.
The mean pK values of corn gluten hydrolysates were obtained as 6.83, 6.59 and 6.36 for 40, 50 and 60 ◦C, respectively