A SURVEY OF AFLATOXIN CONTENTS IN MAIZE, SORGHUM

Abstract

ABSTRACT Using the Thin Layer Chromatographic (TLC) methods of the AOAC procedures, the aflatoxin content of 486 samples of six cereal varieties was determined and 71 (14.6%) of these were found to be positive, anging from 9 mcg/kg to 39.0 mcg/kg. Of these, 23 (32.4%) were maize grains followed by the white sorghum, 12 16.9%) and mixed sorghum, 11 (15.5%). The positive numbers of white, mixed and red teff samples were significantly as low as 7 (9.8%),8(11.3%) and 10 (14.1%), respectively. Similarly, out of the 60 injera samples tested only 1 (5%) sample of teff injera was positive at the 7th day of storage, while 5 (25%) and 7 (35%) samples of maize and sorghum respectively, were positive after the 4th day of storage. In all cases, it was observed that some environmental factors like temperature, moisture content and relative humidity have influenced the aflatoxin formation in the examined samples. It was also confinned that poor storage conditions like open sacs in market areas and warehouses were more conducive to aflatoxin formation than the modern silo bin storage systems. Although the maximum level of aflatoxin yield (39 mcg/kg) determined in this study is not much greater than the accepted standard limit (30 ppb ), it is possible to deduce that maize and sorghum are more susceptible to aflatoxin accumulation than teff grains both before and after baking. In view of these results, therefore, we consider it necessary to recommend some essential measures of controlling food materials for aflatoxin contamination.