Cyanogen removal from cassava roots during sun-drying.

Linamarin levels in sun-drying cassava root pieces showed an exponential decrease, parallel with the moisture loss, and stabilized when moisture levels reached about 15%. Linamarin degradation in thin root segments was significantly slower and less complete than in thick ones. Disinfected longitudinal root halves, oven-dried at 40 °C for 24 h, had significantly higher residual linamarin levels than the matched ones subjected to humid incubation at 25 °C. Interrupting for one or two days the sun-drying of peeled roots resulted in significantly lower residual levels of linamarin and of cyanohydrins plus HCN. Linamarin degradation was greater when the interruption was earlier or longer. The rate of dehydration influences linamarin degradation negatively — mechanisms are discussed. Cyanohydrin removal was completed by prolonged drying.