The proximate chemical composition, the carbohydrate constituents and the amino acid make-up of green and ripe plantain were determined. The quantity of total sugars considerably increased during ripening from 3.0 to 31.6% in the peel and from 1.3 to 17.3 % in the pulp while starch concentration decreased from 50 to 35 % and from 83 to 66% in the skin and the pulp, respectively. The skin was richer in cellulose (10%) and hemicellulose (13 %) than the pulp which had 1.4 % cellulose and 1.3 % hemicellulose. The pulp protein was abundantly rich in arginine, aspartic acid and glutamic acid. Methionine was present in the lowest amount with tryptophan and cystine conspicuously being absent.

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Sucrose formed the bulk of the sugars in cassava root-tubers, accounting for more than 69% of the total sugars. Other sugars included fructose, glucose and maltose. Maltose was consistently present as the lowest amount. The highest concentration of sugars (5.7%) was attained nine months after planting. Starch accounted for the highest proportion of the carbohydrates. A peak value of 81 % was observed eight months after planting. The decrease to 78 % at nine months was accompanied by an increase in sugar concentration from 3.5 % to 5.7 %. The sum of cellulose and hemicellulose constituted the non-available carbohydrate fraction to non-ruminants. This was less than 7% of total carbohydrates. Paper chromatography of the neutralised hydrolysate of the extracted hemicellulose revealed the presence of glucose and xylose only. The amylose content of cassava starch varied between 16.2% and 17.4% during growth. This variation was significant at 1 % F level. The separated amylose had an iodine affinity of 17.0 % while amylopectin had 0.1 %.

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