ABSTRACT
The high utilization and consumption levels of maize in developing countries call
for the investigation of new methods of processing to introduce variety as well as
improve the functionality and nutrient quality of maize-based foods.
This study was carried out to determine the effect of nixtamalization, fermentation
and cowpea fortification on maize and to identify the dominant microflora in
fermented nixtamalized maize. The effect of cooking and lime concentration was
determined using a 2x4 factorial experimental design, with cooking time (0, 30
mins) and lime concentration (0,0.33,0.5 and 1.0%). The cooking time and lime
concentration , significantly influenced the moisture absorption, pH and colour of
the samples. Water absorption capacity was dependent on the lime
concentration. These indices increased with increasing lime concentration used.
The lime did not significantly alter cooked paste viscosity, ash and protein content.
A 3 x 4 factorial experiment was used to study the effect of fermentation on the
characteristics of nixtamalized maize dough. Fermentation resulted in decreased
pH with a corresponding increase in titratable acidity. Fermentation decreased
the texture, water absorption capacity (25°C), cooked paste viscosity and colour
intensity of nixtamalized maize dough. Traditional maize dough facilitated
fermentation, by acting as a starter culture to produce lower pH and higher acidity
in the steeped:nixtamalized maize dough blends.
The central composite rotatable design for K = 3 was used to study the combined
effect of lime concentration (0- 1%), moisture content (55-65%) and cowpea level
(0-30%) on pH, titratable acidity, water absorption, texture, protein and viscosity
of nixtamlized maize dough (masa) during fermentation. The lime and cowpea
influenced the titratable acidity, water absorption capacity, protein content and the
cooked paste viscosity of the fermented cowpea fortified nixtamalized maize.
Increasing concentration of lime, during fermentation, generally decreased
titratable acidity, water absorption, work required to back extrude an amount of
cooked set slurry and cooked paste viscosity while the addition of cowpea
increased most of these indices.
The final pH and titratable acidity of the fermented nixtamalized maize were
comparable to that of the traditional maize dough. The microbial counts obtained
(aerobic mesophiles and lactic acid bacteria) for the nixtamalized maize and
traditional maize dough, were comparable after 24 hours of fermentation. Yeast
counts were slightly lower in the fermented nixtamalized maize dough. These
results showed that nixtamalized maize dough lends itself well to traditional
spontaneous fermentation with the resultant souring and development of the
characteristic flavours of traditionally fermented maize. The Lactic acid bacteria
identified in the fermented masa were L. plantarum, L. fermentum and L.
cellobiosus. Pediococcus spp. were also identified (found in fermented masa).
CORNELIUS, B (2021). CHEMICAL MODIFICATION AND COWPEA FORTIFICATION OF MAIZE. Afribary. Retrieved from https://afribary.com/works/chemical-modification-and-cowpea-fortification-of-maize
CORNELIUS, BEATRICE "CHEMICAL MODIFICATION AND COWPEA FORTIFICATION OF MAIZE" Afribary. Afribary, 31 Mar. 2021, https://afribary.com/works/chemical-modification-and-cowpea-fortification-of-maize. Accessed 14 Nov. 2024.
CORNELIUS, BEATRICE . "CHEMICAL MODIFICATION AND COWPEA FORTIFICATION OF MAIZE". Afribary, Afribary, 31 Mar. 2021. Web. 14 Nov. 2024. < https://afribary.com/works/chemical-modification-and-cowpea-fortification-of-maize >.
CORNELIUS, BEATRICE . "CHEMICAL MODIFICATION AND COWPEA FORTIFICATION OF MAIZE" Afribary (2021). Accessed November 14, 2024. https://afribary.com/works/chemical-modification-and-cowpea-fortification-of-maize