We studied the effects of traditional lactic acid fermentation and the addition of malt on the physicochemical properties of maize-cowpea blends. The products were high in protein (18.4%-19.4%) and low in fat (0.5%-1.3%) and fibre (0.5%-0.7%). Fermentation reduced the pH from 6.7 to 4.4. The unfermented sample without malt was about four times as thick in consistency as those containing it. Up to 5% malt in the blends did not reduce the viscosity of the cooked samples fermented for two days. Fermentation for three days further neutralized the known effects of reducing viscosity by the addition of malt. Two different effects occurred when fermented blends containing malt were cooked: malt addition caused a reduction in viscosity, whereas fermentation led to an increase.
Thus adding malt to maize-cowpea blends before fermentation does not reduce viscosity. Adding malt to the blend after fermentation should be tried.
References
1.
Food and Agriculture Organization.Amino acid content of foods. Nutritional Studies no. 24.Rome: FAO, 1970.
ChavanU.D., ChavanJ.K., KadamS.S.Effects of fermentation of soluble proteins and in vitro protein digestibility of sorghum, green gram and sorghum-green gram blends. J Food Sci1988; 53: 1574–5.
4.
NoutM.J.R., RomboutsF.M., HavelaarA.Effects of accelerated natural lactic fermentation of infant food ingredients on some pathogenic microorganisms. Int J Food Microbiol1989; 8(4): 351–61.
5.
WestbyA., GallatS.The effect of fermentation on the viscosity of sorghum porridge. Trop Sci1991; 31: 131–9.
6.
MensahP., DrasarB.S., HarrisonT.J., TomkinsA.M.Fermented cereal gruels: towards a solution of the weanling's dilemma. Food Nutr Bull1991; 13(1): 50–7.
7.
AshworthA., DraperA.The potential of traditional technologies for increasing the energy density of weaning foods: a critical review of existing knowledge with particular reference to malting and fermentation. WHO Technical Report Series.(WHO/CDD/EDP) 92.4) Geneva: WHO, 1992.
8.
MoshaA.C., SvanbergU.Preparation of weaning foods with high nutrient density using flour of germinated cereals. Food Nutr Bull1983; 5(2): 10–14.
9.
GopaldasT., MehtaP., PatilA., GandhiH.Studies on reduction in viscosity of thick rice gruels with small quantities of an amylase-rich cereal malt. Food Nutr Bull1986; 8(4): 42–7.
10.
GopaldasT., DesphandeS., JohnC.Studies on a wheat-based amylase-rich food. Food Nutr Bull1988; 10(3): 559.
11.
MareroL.M., PayumoE.M., LibrandoECTechnology of weaning food formulations prepared from germinated cereal and legumes. J Food Sci1988; 53: 1391–5.
12.
HansenM., PedersenB., MunckL., EggumB.O.Weaning foods with improved energy and nutrient density prepared from germinated cereals: 1. Preparation and dietary bulk of gruels based on barley. Food Nutr Bull1989; 11(2): 40–5.
13.
AlvinaM., VeraG., PakN., ArayaH.Effect of the addition of malt flour to extruded pea-rice preparations on food and energy intake by preschool children. Ecol Food Nutr1990; 23: 189–93.
14.
Sefa-DedehS., AmpaduE.W.Chemical and functional properties of cereal/legume blends. In: Sefa-Dedeh S. ed. Development of high protein-energy foods from grain legumes: proceedings of an international workshop.Legon: University of Ghana, 1991: 49–61.
15.
JohnC., GopaldasT.Reduction in the dietary bulk of soya-fortified bulgur wheat gruels with wheat-based amylase-rich food. Food Nutr Bull1988; 10(4): 50–3.
16.
Association of Official Analytical Chemists.Official methods of analysis. 12th ed.Washington, DC: AOAC, 1975.
17.
AkpapunamM.A., MarkakisP.Physicochemical and nutritional aspects of cowpea flour. J Food Sci1981; 46: 972–3.
18.
DuboisM., GillesK.A., HamiltonJ.K., RibersP.A., SmithF.Colorimetric method for determination of sugars and related substances. Anal Chem1956; 28: 350–6.
19.
Protein-Calorie Advisory Group of the United Nations System.Marketing protein-rich foods in developing countries. PAG Guideline no. 10. In “Developing countries,” in: Compendium 14/10: G.New York: John Wiley and Sons, 1975: 405–500.
20.
MitznerK., ScrimshawN., MorganR.Improving the nutritional status of children during the weaning period: a manual for policy makers, program planners, and field workers.Cambridge, Mass, USA: Home- and Village-Prepared Weaning Foods Project, MIT, 1984.
21.
AkpapunamM.A., AchinewhuS.C.Effects of cooking, germination and fermentation on the chemical composition of Nigerian cowpea (Vigna ungiculata). Plant Foods Hum Nutr1985; 35: 353–8.
22.
RasperV.Theoretical aspects of amylographology. In: Shuey WC, Tipples KE, eds. The amylograph handbook. St.Paul, Minn, USA: American Association of Cereal Chemists, 1980.
Sefa-DedehS.Evaluation of the physico-chemical and processing characterisitcs of improved varieties of maize grown in Ghana.Legon: University of Ghana, 1993.
