ISI 39-1e Determination of Conductivity of Starch

1. Scope The method is applicable to native and modified starch.

 

 LT 1989
Rev. LT 09 Sep. 1999
2. Principle Conductivity is measured in the water phase of a starch slurry

 
3. Apparatus 3.1 Conductivity meter with probe and temperature correction  Properly calibrated
3.2 Laboratory scale

 
4. Procedure Weigh sample on (3.2) to the nearest g in a  beaker Ambient   temperature

Commercial starch:

 Add the equivalent quantity of distilled water and stir for minimum 10 minutes. The starch is allowed to settle. Measure conductivity of the water phase. Approx. 22 oBé

Starch slurry:

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

 
5. Reporting Report conductance as mS per cm (mScm-1) with two decimals

 

 mS = milliSiemens
S = ohm-1
6. Notes It essential to measure in a clear water phase free of starch, foreign particles and air affecting conductivity. Filter if nessesary.

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