EVALUATION OF THE MICROBIOLOGICAL QUALITY OF INDIGENOUS COMPLEMENTARY FOODS IN KANO STATE

Abstract

Locally (Indigenous) prepared complementary foods are widely consumed by infants in Nigeria because of their affordability and accessibility; however, their microbiological safety remains a major public health concern. This study evaluated the microbiological quality of three locally prepared complementary food samples (Samples A, B, and C) sold in Tarauni Local Government Area, Kano State, in comparison with a laboratory-prepared counterpart (Sample D). The market samples were unbranded, powdered formula, and sold under open conditions, potentially exposing them to contamination. Standard microbiological methods were employed: Nutrient Agar for aerobic mesophilic bacterial counts, Potato Dextrose Agar for fungal isolation, and the Most Probable Number (MPN) method for coliform estimation, while pathogens were identified through biochemical tests. The aerobic mesophilic bacterial counts of the locally prepared foods ranged from 2.45 × 10⁶ to 1.08 × 10⁷ CFU/mL, exceeding the WHO permissible limit of 1.0 × 10³ CFU/mL. Fungal contaminants detected included Aspergillus niger, A. fumigatus, and A. flavus. Coliform counts reached up to 150 MPN/100 mL, and pathogens such as Escherichia coli, Staphylococcus aureus, and Shigella spp were present in the market samples but absent in the laboratory-prepared food, which remained within safety limits. These findings reveal significant microbiological risks associated with locally prepared complementary foods. Strengthening vendor hygiene practices, enforcing regulatory surveillance, and promoting laboratory-standard local formulations are recommended to safeguard infant health.