Some chemical components of Nigerian cassava cultivars and of the processed product

Abstract

A study of the protein, HCN and mannitol contents of the leaves and tuberous roots as well as gari preparations from different cassava varieties cultivated in the major cassava growing areas of Nigeria was undertaken. Leaf protein content averaged 21.4 percent, tuber protein fanged between 1.95-2.18 percent and gari protein content averaged 0.84 percent of dry weight.
The cyanogenic glucoside (HCN) content of the leaf was about ten times that of the peeled tuber while the peel contained 4-6 times as much HCN as the edible cassava tuber. Although leaf HCN content significantly correlated with the HCN content in the tuber (P = 0.05) , no linear relationship was found between leaf protein and tuber protein content. Most of the cyanide in the fresh material is eliminated during processing.
The gari processed from the cassava cultivars contained safe levels of prussic acid and there was practically no difference in the HCN content (11.8-28.5 ppm) of the gari prepared from the so-called sweet and bitter cassava cultivars.