The effects of different packaging materials, temperatures and water activities to control aflatoxin B₁ production by Aspergillus flavus and A. parasiticus in stored peanuts

Aflatoxins (AFs) are secondary metabolites produced by aflatoxigenic strains of Aspergillus flavus and A. parasiticus, the most toxic being aflatoxin B₁ (AFB₁). The purpose of the present work was to investigate the effects of industrial-grade packaging materials (low-density polyethylene, polypropylene, polyethylene-laminated aluminium); temperatures (25 °C, 30 °C); and water activities (0.74 a _w, 0.85 a _w) on AFB₁ production by A. flavus and A. parasiticus in stored peanut kernels. Commercially-obtained samples were segregated into packaging materials, separately inoculated with the aflatoxigenic Aspergillus spp., and stored for 1 month under various °C + a _w regimes. AFB₁ production was quantified by high performance liquid chromatography with fluorescence detector (HPLC-FLD). For A. flavus in PELA, no AFB₁ was detected (100% reduction) at 25 °C for both a _w tested. For A. parasiticus in PELA, no AFB₁ was detected at 25 °C (0.85 a _w) and 30 °C (0.74 a _w). Highest concentration of AFB₁ was detected in LDPE for both A. flavus (46.41 ppb) and A. parasiticus (414.42 ppb), followed by PP (A. flavus 24.29 ppb; A. parasiticus 386.73 ppb). In conclusion, storing peanut kernels in PELA in a dry place at room temperature has been demonstrated as an adequate and inexpensive method in inhibiting growth of Aspergillus spp. and lowering AFB₁ contamination in peanuts.