Preparation of linamarin from cassava leaves for use in a cassava cyanide kit

A simple method is described for the preparation, from very young cassava leaves, of a dilute hydrochloric acid solution of linamarin. Linamarin extraction from the leaves is virtually quantitative. The linamarin solution is used in the preparation of standard linamarin filter paper discs that are needed to monitor the performance of picrate kits for determination of the total cyanide content of cassava roots and cassava products. These standard discs are stable indefinitely if stored in the refrigerator, but very slowly lose linamarin activity if stored for more than one month at room temperature.