Kinetics of aflatoxin degradation during peanut roasting

- The aflatoxin degradation rate for different initial concentration was determined.
- Roasting at 160, 180, 200 °C resulted in aflatoxin reduction of 61.6, 83.6, 89.7%.
- Roasting impacted on peanut colour and lead to aflatoxin levels reduction.

This study investigated aflatoxin degradation during peanut roasting. First, peanuts contaminated with three initial aflatoxin concentrations (35, 332 and 695 μg/kg) were roasted at 180 °C for up to 20 min. The percentage of aflatoxin degradation after 20 min were 55, 64 and 81% for peanuts contaminated with aflatoxin at 35, 332 and 695 μg/kg, respectively. This difference was statistically significant (p < 0.05), showing that initial concentration influences aflatoxin reduction. Thereafter, peanut samples contaminated with an initial aflatoxin concentration of 85 μg/kg were roasted at 160, 180 and 200 °C for 5, 10, 15, 20 and 25 min, then residual concentrations of aflatoxin were determined. Roasting at 160, 180 and 200 °C resulted in an aflatoxin reduction of 61.6, 83.6 and 89.7%, respectively. This study has provided quantitative data reinforcing the fact that roasting alone is not enough to control aflatoxins in peanuts.

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