Apart from its use as a source of power, the availability of ample pure water is of the utmost importance in processing cassava flour. During the greater part of the process, the starch granules are in contact with water which, besides the soluble constituents of the roots, contains all the substances originating from the water added in wet-screening of the pulp and in sedimentation. The deleterious effect of crude suspended matter in the water used (turbidity from clay, etc.) will be obvious. Moreover, starch in its natural state acts as a moderately strong absorbent of electrolytes and colloidal matter in solution. As a result, any ions in the water, even if present in small concentrations, are apt to be accumulated in the granules, thus influencing the outward appearance and the physicochemical properties of the flour.