Production of Aflatoxin on Peanuts under Controlled Environments

Abstract

The influence of temperature, relative humidity, nature of the substrate, atmospheric gases, and other factors on growth and aflatoxin production by Aspergillus jlavus in peanuts, Arachis hypogaea L. variety 'Early Runner', was investigated under controlled environments. Sound or broken mature kernels, immature kernels, and unshelled peanuts were inoculated with spores of A. jlavus and incubated in 98 ± 1 per cent r.h. at temperatures ranging from 10 to 45°C, and also 30 ± O· 5°C in relative humidities ranging from 70 to 99 per cent. The substrate was either heat-treated (sterile) cured peanuts, surface-sterilized pods of freshly dug peanuts, or unsterile cured peanuts. Surface-sterilized, sound mature kernels were used in studies with atmospheric gases. Samples were removed after 7, 21, 42, or 84 days and assayed for aflatoxin, free fatty acids, and kernel moisture.