A Comparative Evaluation of the Macronutrient and Micronutrient Profiles of Soybean-Fortified Gari and Tapioca

Abstract

Gari and tapioca are storage-cupboard convenience foods obtained from the tubers of cassava (Manihot esculenta Crantz). They are important staples in Nigeria and many African countries where malnutrition is a major problem. Tapioca is a quick-cooking food made from partly gelatinized starch and gari is a fermented, roasted, granular food made from cassava pulp. Gari and tapioca are nutritionally inferior and need to be fortified. This paper reports the macro- and micronutrient profiles of soybean-fortified gari and tapioca. Gari and tapioca were fortified with soybean flour or soybean residue at 25% of dry weight. Standard methods were used for the determination of proximate parameters such as crude protein, fat, ash, carbohydrate and moisture content. All the samples were analyzed for phosphorus, calcium, magnesium, potassium, sodium, manganese, iron, copper and zinc. Unfortified tapioca had significantly lower (p < .05) proximate values (protein: 0.31%; fat: 0.17%; ash: 0.34%) than unfortified gari (protein: 1.50%; fat: 1.56%; ash: 1.35%). The fortification of both gari and tapioca significantly (p < .05) increased the contents of crude protein, phosphorus, fat, and ash as well as all the monitored macro- and micronutrients. These values (%) increased from 1.50-9.31, 0.06-0.11, 1.56-4.31 and 1.35-1.64 for gari-soybean fortified gari; and 0.31-12.56, 0.03-0.12, 0.17-5.45 and 0.34-1.41 for tapioca to soybean fortified tapioca respectively. Soybean flour increased the nutrient content of the fortified gari and tapioca compared to soybean residue. Data from this study suggest that both soybean flour-fortified tapioca and soybean flour-fortified gari are effective means of meeting the daily requirements of minerals, protein, and energy. Both soybean flour-fortified tapioca and soybean flour-fortified gari could be used to fight macronutrient and micronutrient deficiencies, not only in Nigeria and other African countries where these two cassava products are staples, but also in other cassava-consuming developing nations.