Cereal Chem 68:165-169   |  VIEW ARTICLE

Studies on Weaning Diets in Nigeria. I. Carbohydrate Sources.

S. R. A. Adewusi, B. O. Orisadare, and O. L. Oke. Copyright 1991 by the American Association of Cereal Chemists, Inc. 

Ogi is a fermented cereal porridge and a popular weaning, breakfast, and convalescent food in Nigeria. It is made from sorghum in the northern part of the country, where sorghum is cultivated abundantly, and from maize in the heavy rain belt of the south. In this study, ogi was made from white and yellow maize and from white and red sorghum and compared with other carbohydrate sources in a simulated weaning diet. The yield of ogi was 66.0-75.9%, and the protein content was 7.53-9.28%, compared with 8.05% for breadfruit and 1.05% for cassava starch. Reducing sugar was 2.85% in breadfruit and 0.03-0.08% in the others. White sorghum ogi contained the highest energy (4.07 kcal/g) and the lowest ash (0.32%), whereas cassava starch contained the lowest energy (3.38 kcal/g) and the highest ash (3.91%). Fat content was 5.5% in maize ogi, 2.97% in sorghum ogi, and 1.92% in breadfruit. Processing grains into ogi reduced the tannin content by 64-100% and phytate by 72-93%. Cyanide was not detected in sorghum ogi or cassava starch. In the rat bioassay, feed intake was highest (78.3 g) in a red sorghum ogi-casein diet (13% protein level) and lowest in a corn starch diet (59.4 g). Weight gain, protein efficiency ratio, and net protein ratio values were highest in the cassava diet (25.2, 2.6, and 3.9 g, respectively), followed by breadfruit and corn starch; the lowest values were recorded with a white sorghum ogi diet (weight gain 9.5 g, protein efficiency ration 1.0, and net protein ratio 2.2). Protein digestibility was high (93.0-97.1%) for all diets. In vitro starch digestibility was highest in corn starch, followed by breadfruit, and lowest in white sorghum and yellow maize ogi. Using a first-order kinetics equation, breadfruit had the highest initial rate of starch hydrolysis (t1/2 for 19.4 min), followed by corn starch (26.1 min); the lowest was for white sorghum ogi (109.7 min). The bioassay results were therefore explained in terms of starch digestibility and gastric emptying.