Production, Isolation and Identification of Microbes in Home-made Complementary Food Flour Based on Maize-Pigeon Pea Flour

Abstract

Maize (zea- mays) and pigeon pea (Cajanus cajan) were processed into flour by local methods (malting/germination and fermentation) and used in formulating composite complementary foods at different proportions (75:25%), (25:75%) and (50:50%) respectively. The blends were formulated according to fermented maize to fermented pigeon pea, germinated maize to germinated pigeon pea respectively. The microbial contents of the raw maize flour, raw pigeon pea flour and the processed samples were evaluated using standard microbiological methods.. The total heterotrophic bacterial count (13.6 x 106cfu/ml), total heterotrophic fungal counts (3.0 x 106cfu/ml), total coliform counts (11.6 x 106cfu/ml), and total microbial isolates were all higher in the raw flour compared to the processed flour (4.2 x 106cfu/ml, 1.0 x 106cfu/ml, 4.2 x 106cfu/ml, 1.0 x 106cfu/ml and 3.0 x 106cfu/ml) respectively. The bacteria isolated were predominantly in the raw flour mainly Bacillus spp, Staphylococcus aureus, Lactobacillus sp, Pseudomonas sp, Escherichia coli, Klebsiella sp, Proteus sp and Streptococcus sp. The fungal isolates were Aspergillus niger, Aspergillus flavus, Penicillin sp, Geotrium sp, Trichophytum rubrium, candida sp and Rhizopus sp. Indicator microorganisms were isolated only in the raw maize and pigeon pea but were not observed in the germinated, fermented and composite blends. Microbial load in the processed and composite blends fall within the level of acceptance (104 - < 106cfu/ml) of the microbiological reference criteria for such foods. This work, therefore concludes that raw flour samples are not suitable as complementary food in the feeding of children.