Abstract:

The effect of replacing 25% of the basic maize flour with groundnut paste (xv/w) and/or 10% of die liquid ingredients with
fresh dairy milk (v/v) on the viscosity and energy density of weaning maize porridge was investigated in a 2X fractional
factorial experiment. Other factors investigated included (i) particle size of the flour (ii) concentration of the porridge (iii)
cooking time (iv) the temperature of the porridge at the time of viscosity measurement and (v) the shear speed and shear
time of the viscometer during viscosity measurements. The viscosity of the porridge
was measured using a rotational
determined by calculation from the proximate values of the raw ingredients. The
viscometer while its energy density was
results showed a significant reduction in the viscosity of the maize porridges due to addition of groundnut paste (P<0.001)
or fresh dairy milk (P<0.001). Overall, groundnut alone decreased the viscosity of the porridges by 56.1%. milk alone by
26.0% a ii(I groundnut plus milk by 64.9%. The influence of (he addition of groundn ut on the viscosity of the porridges was
significantly influenced by concentration of the porridge (P<().001), shear speed (P<0.0I), cooking time (Pv0.025) and flour
particle size (P<0.0S) with groundnut reducing the viscosity more at higher concentrations, lower shear speeds, higher
cooking times a nd \vith fine particle-sized flour. The influence of addition of dairy milk on the viscosity of the porridges
was significantly influenced by concentration (P<0.001) and flour particle size (P<0.05) with milk reducing the viscosity
more at higher concentrations and with fine particle-sizcd flour. The energy density of the porridges was substantially
increased by addition of groundnut alone (11.5%). milk alone (25.0%) and groundnut plus milk (36.4%). These results
indicate that the viscosity of weaning maize porridges can be reduced and the energy density increased by supplementation
with groundnut paste and/or dairy milk. As energy deficit has been found to be the most significant fifetor in the aetiology
of protein-energy malnutrition (PEM), it is therefore rcconimended that weaning cereal porridges should be supplemented
with energy-rich foods