Studies on the hydrocyanic acid contents of some local varieties of cassava (Manihot esculenta Crantz) and some traditional cassava food products.

Abstract

For a different set of four varieties in each case tabulated data are presented on (1) distribution of HCN in different plant parts, (2) transverse distribution of cyanide in the plant, especially the tuber, (3) cyanide concentration in fresh and cooked cassava leaf and tuber tissues and (4) cyanide concentrations in fresh tubers, soaked tubers and tubers that had been soaked and then dried. Sweetness or bitterness, by which varieties are judged for palatability, were not always correlated with HCN content.ADDITIONAL ABSTRACT:Four varieties of cassava contained in young leaves 568 to 620, mature leaves 400 to 530, tuber bark 608 to 950 and tuber pulp 45 to 330 mg HCN/kg. The inner part of the tuber contained less than the outer part. Boiling reduced the amounts considerably. Cassava flour made by a traditional process contained harmless amounts similar to that of flour bought in a market.