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Estimation of Hydrogen Cyanide Released from Cassava by Organic Solvents

Published online by Cambridge University Press:  03 October 2008

Hugh J. Williams
Hugh J. Williams
Affiliation:
Njala University College, University of Sierra Leone, PMB, Freetown, Sierra Leone
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Summary

Methods are described for releasing HCN from cassava leaves and tubers by organic solvents and its spectrophotometric estimation as the red complex formed with alkaline picrate. Chloroform was the most efficient solvent, with toluene an acceptable alternative, using enough solvent to wet samples thoroughly to maximize cyanide yield. Cyanide content was concentrated in the veins and towards the base of leaves and declined linearly with leaf age. Release of HCN with solvent compared favourably with traditional homogenization/steam distillation with leaves and parenchymal tissue, but was unsatisfactory for tuber peel. The effective removal of HCN from cooked cassava leaves depends chiefly on release of enzymes by efficiently chopping them before boiling, which only slowly destroyed potential cyanide content of unchopped leaves.

Information

Type
Research Article
Information
Experimental Agriculture , Volume 15 , Issue 4 , October 1979 , pp. 393 - 400
Copyright
Copyright © Cambridge University Press 1979

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References

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