Silage Assessment by Potentiometric Titration

The computer-controUed method of titration involved was developed by Moisio and Heikonen [44]. Its apphcation to silage press-juice provides for the determination of lactic acid, acetic acid, reducing sugars, amino acid carboxyl groups and the protein degradation products -NH2 and -NH- groups. The general method follows. 

00 mL of silage press-juice is pipetted to the titrator vessel and 10.0 mL of water added automatically. 

The titrator first measures the pH of the sample, and then adds 1 M HCl until the pH falls below 2. 1 M NaOH is then added in monotonous 

010 mL increments until the pH exceeds 11.9. The pH value and the volume after each addition is stored in the computer memory. 

The time interval between additions is selective, but is usually 300 ms. AH data is measured at the buffering capacity maximum, where the pH changes slowly and measurements are most accurate. 

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