ISI 33-2e Determination of Baumé of Starch Slurry by Centrifugation


1. Scope The method is applicable to starch slurry

 

 LT 15 Jan 1998
2. Principle Volume of starch sediment after centrifugation is interpreted as concentration of slurry

 
3. Apparatus 3.1 Centrifuge with free swinging rotor, manual or electrically powered
3.2 Centrifuge tube 15 ml with 0.1 ml marks 0-10 ml and mark at 15 ml

 
4. Procedure Fill tube (3.2) with 15.0 ml starch slurry.
Spin in centrifuge until all starch has settled. remember counter weight
Read sediment in ml (V) to the nearest 0.1 ml

 
5. Calculation Report starch concentration of slurry with one decimal in degree Baumé (Béo) = fV

 

 Use factor f = 2 for potato starch. Determine factor f  for other starches empirically.
6. Note The centrifuge is superior to the aerometer as a process tool being indifferent to entrapped air and rapid settling starch.
With Baumé as entry table values of density etc may be found ISI Starch Slurry Viscosity Table

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