Effect of storage conditions and packaging material on the accumulation of aflatoxin in maize grains

Grains of hybrid maize (PMH-1) with initial moisture content of <12, 12.1–20 and >20 per cent were stored up to one month at three different temperatures (25±2°C, ambient temperature and 35±2°C) in three different packaging materials (cotton cloth, gunny and high density polythene bags) and artificially inoculated with the toxigenic isolate of Aspergillus flavus (Af 5). Aflatoxin production was detected only in high density polythene bags. At zero day storage, AFB₁ was detected only in grains with initial moisture content of >20 per cent at ambient temperature (29±2°C). After 30 days of storage, aflatoxin production was maximum at >20 per cent moisture content with temperature 35±2°C and minimum at <12 per cent with temperature 25±2°C. After 30 days of storage, AFB₁ was detected in all the treatments except at 25±2°C with moisture content of >20 per cent in which AFB₂ was detected. Spore density after 30 days was also maximum at >20 per cent moisture content with temperature 35±2°C. Aflatoxin production was found directly proportional to increase in temperature, moisture content and spore density.