Microorganisms Associated with the Fermentation of Gari Fortified with Sprouted Mung Beans Flour

Abstract

Gari’ is consumed regularly by large populations of Nigeria, therefore, it is an excellent means of improving the diet of people through fortification with nutritionally rich foods hence, this study aim to produce ‘Gari’ by co-fermenting cassava mash and sprouted mung bean flour in different ratios in order to assess the effect on the nutritional composition as compared to a standard produced without sprouted mungbeans (SMF) flour fortification. In different ratios, composites of cassava mash (CM) and the sprouted mungbeans flour (SMF) were made (5% SMF + 95% CM, 10% SMF + 90% CM, 15% SMF + 85% CM; and 100% CM which serve as the control) and fermented using semi-solid state fermentation for four days. The Gari was then produced following the standard method of dewatering, sieving and roasting. Isolation of microorganism during the fermentation was carried out using standard microbiological techniques and identification was done using conventional and molecular techniques. The total bacterial (cfu/ml) of the fermented samples increased during the first day of fermentation, and reduced on subsequent days in all samples with the bacterial count ranging from 1.21 x105 CFU/g to 2.45 x105 CFU/g. The organisms isolated include Lysinibacillus alkalisoli, Proteus mirabilis, Pediococcus acidilactici, Lactobacillus plantarum, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Penicillium sclerotiorum, Diutina catenulate, Rhizopus stolonifer, Trichoderma viridae, Saccharomyces cerevisiae. Most of the organisms isolated during the first and second day of fermentation such as Proteus spp, Staphylococcus spp, Bacillus spp, Bacillus spp, Diutina spp and Trichoderma spp, later disappeared toward the later days of the fermentation. Lactic acid bacteria, mold and yeast isolates such as Lactobacillus plantarum, Pediococcus spp. Penicillium spp and Saccharomyces cerevisiae dominate toward the later stage of the fermentation in all the fermented samples. Molecular identification of the bacterial isolates shows that Lysinibacillus alkalisoli, Proteus mirabilis, Pediococcus acidilactici, Lactobacillus plantarum, Staphylococcus aureus, Bacillus subtilis and Bacillus cereus were present in the samples. The outcome of this research showed that co-fermentation of cassava mash and sprouted mung bean flour eliminates pathogenic microorganisms and encourages the growth of beneficial microorganism in mung bean fortified Gari production.