NUTRITIONAL AND AFLATOXIN CONTENT OF DIFFERENT OGI VARIETIES SOLD IN BENIN CITY

ABSTRACT

There is a need to improve the nutritional value of food and check the aflatoxigenic content of foods especially those frequently exposed to toxigenic fungi species. The aim of this study was to determine the nutritional and aflatoxin content of ogi varieties. Three grain samples (yellow corn, white corn and millet) were purchased from Oba market, New Benin market and Satana market in Benin City, Edo State. Samples were analyzed before and after fermentation to determine their mycological, nutritional and aflatoxin levels using standard microbiological methods. Pour plate method was used for isolation, Enzyme Linked Immunosorbent Assay (ELISA, AgraQuant) was used to determine the aflatoxin, Near Infra-red Spectroscopy Machine at wavelength 780nm - 2500n was used for the proximate analysis. Paired sample statistics ANOVA were used to analyze data in SPSS environment. Fungi count on Saboroud Dextrose Agar (SDA) for pre-fermented (0hr) maize ranged from 44.50±2.50 cfu/g to 185.50±25.50cfu/g and for post-fermented maize (72hr) ranged from 1.5±0.5 cfu/g to 118.00±46.00 cfu/g. On Potato Dextrose Agar (PDA) the fungi count for pre-fermented maize ranged from 30.5±8.5 cfu/g to 246.50±17.50 cfu/g and for post-fermented maize ranged from 10.50±1.50 cfu/g to 146.50±46.50 cfu/g. It was observed that there was statistically significant difference between the fungi count recorded pre and post fermentation (P > 0.001). The aflatoxin content ranged from 35.20±0.60 ppb to 59.50±0.40 ppb pre-fermentation and 12.70±1.70 ppb to 28.70±1.25 ppb post-fermentation; there was statistically significant difference in aflatoxin recorded pre and post fermentation (P > 0.001). Proximate analysis showed 69.50%, 9.30%, 8.90%, 4.40%, 3.80% and 4.10% for carbohydrate, moisture, protein, ash, fiber and fat respectively. Although fermentation reduces the aflatoxin level as observed in this study, high aflatoxin content was recorded in ogi (28.70±1.25 ppb/46.20±1.30 ppb). This exposes consumers to the adverse health impact like immunosuppression, infertility, cancer etc. associated with aflatoxin consumption, therefore stringent measures should be employed to control consumptions of such foods.