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A comparison of simple methods for estimating starch content of cassava roots showed a strong relationship between root specific gravity and root dry matter content. In the absence of drying facilities a specific gravity balance appears adequate to separate root samples according to dry matter content. A strong relationship between root specific gravity and starch content was observed using a maceration/sieving technique. This relationship was close to a published relationship based on chemical analysis. Root dry matter content may be used as an indication of starch content but care should be exercised in using linear conversions until more information becomes available. Existing conversion tables from root specific gravity to starch content and the starch content calibrations on the Reimann balance used, grossly underestimated starch content of the samples analysed.

The rapid post-harvest deterioration of cassava roots, which usually prevents their storage in the fresh state for more than a few days, is poorly understood. Two types of deterioration are defined, namely primary, shown by internal root discoloration, and secondary, caused largely by wound pathogens. Information is presented on the influence of such factors as mechanical damage and plant cultivar upon the development of the two types. Control of primary, and a reduction in secondary, deterioration is achieved during a curing process, but none of the chemical treatments examined gave consistent practical control of deterioration.

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