Abstract:
The determination of the dry matter content of cassava tubers using oven dry method is a major constraint in
tropical developing countries where the source of electricity is unreliable. In this study a prediction equation was
developed as an alternative approach to dry matter determination with the oven dry method. The study was conducted for
two years with eleven cassava accessions (using 13 and 15 month old tubers). In the first year, the specific gravity and the
dry matter content (oven dry method) of the same tubers were used to derive the prediction equation that can be used for
easy and faster estimation of the dry matter content of cassava tubers. The specific gravity and dry matter content based on
the oven dry method ranged from 1.0966-1.1469 and 31.45-40.74%, respectively. There was a perfect correlation (R2 =
0.9979) between specific gravity and oven dry matter content of cassava tuber. The middle portion of the cassava tubers
gave the true representation of the dry matter content. The prediction equation developed was Y = - 175.46 + 188.61 X
where: X = specific gravity and Y = percentage dry matter content. The dry matter content based on the prediction
equation for the various accessions was found to be between 31.88-41.53% with a mean of 38.39%. The chi-square test
conducted at probability level of 0.05 shows that there was no significant difference between percentage dry matters
estimated using the oven dry method and the prediction equation. Hence, the prediction equation could be used to estimate
the percentage dry matter content of cassava tuber if the specific gravity is known.
