The sediment was sifted successively through screens of
20 and 300 US mesh.
In each mesh, the residue was washed with 150 mL of deionized water until a gold-coloured mass was left with no apparent leakage of starch (wash water clear).
The resulting starchy suspension was centrifuged (10000g, 4 1C, 30 min) and the supernatant was discarded.
The precipitate formed two layers, the upper brown and slimy in appearance and the lower white (starch).
The white starch residue was resuspended in an aqueous solution of 0.1 M NaCl:toluene (7:1 v/v) and then homogenized and stirred overnight at 4 1C.
The suspension was centrifuged (7000g, 4 1C, 30 min) so that two phases were formed: the proteins, fat and small granules not separated by centrifugation in the toluene phase; and a starch-rich fraction in the aqueous phase.
This fraction was washed repeatedly with a NaCl–toluene mixture.
The isolated starch was dried in a convection oven at 35 1C for 24 h, carefully ground in a mortar and stored at room temperature (25 1C) in airtight plastic bags.