Fate of aflatoxin B₁ during fermentation of maize into \"ogi\"

Abstract

The fate of aflatoxins in fermented maize (Ogi) was investigated. The effect of spontaneous fermentation and storage under refrigeration temperature (4°C) and ambient tropical condition (28°C) was studied. Levels as high as 50µg/kg was recorded for the control sample. Aflatoxins present in the maize grains persisted after 24 to 48 hours period of fermentation. However, there was a 50% reduction after 72 hours of fermentation of maize (50µg kg^-1 to 25µg kg¹) which was statistically significant at p<0.05. Analysis of the bran showed that there was no adsorption of aflatoxin at 24 hours and 48 hours of fermentation. There was 50% adsorption of aflatoxin to the bran from the fermented maize grains after 72hr fermentation period. Organisms isolated from fermented maize grains were Corynebacterium spp., Fusasium spp., Aspergillus spp., Penicillium spp., Lactobacillus spp., Leucosnostoc spp., Lactococcus spp,. The pH values of 0-72hr fermented maize grains range between 2.95 and 6.85. There was no effect of storage on aflatoxin content of ogi at ambient and refrigeration temperatures.

Keywords: aflatoxin B₁, fermentation, maize, ogi

Nigerian Food Journal Vol. 23 2005: 243-247