ISI 26-5e Determination of pH in Starch and Syrup

1. Scope The method is applicable to native and modified starch, glucose syrups and hydrolysates.

 

 LT 1966
Rev. LT 13 Sep. 1999
2. Principle pH is measured electrometrically in the water phase of a starch slurry or direct in hydrolysates and syrups.

 
3. Apparatus 3.1 pH meter glass electrode and temperature correction  Properly calibrated
3.2 Laboratory scale

 
4. Procedure Ambient   temperature

Commercial starch:

 Shake 5.0 g sample with 25.0 ml distilled carbon dioxide free water for 60 s. The starch is allowed to settle for 15 min. Measure pH of the water phase. The European Pharmacopoia

Pregelatinised starch

 Shake 5.0 g sample with 25.0 ml distilled carbon dioxide free water for 60 s. The starch is allowed to settle for 15 min. Measure pH of the water phase. The European Pharmacopoia

Starch slurry

 The starch is allowed to settle. Measure pH of the water phase.

Glucose Syrup:

 Dilute sample to approximately 40% dry matter with distilled water. Measure pH of the diluted syrup

HFSS:

 Measure pH of sample as is.

 
5. Reporting Report pH with one decimal

 
6. Reference CRA Standard Analytical Methods B-44, C-44, E-48Joint FAO/WHO Expert Committee on Food Additives (JECFA) Monographs and Evaluations
The European Pharmacopoia 4

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