Extraction of Aflatoxin from Peanut Meal and Kernels by CO₂-Methanol Using a Highly Pressurized Fluid Extraction...

Peanut kernels infected with Aspergillus parasiticus after milling into meals were used as toxin-contaminated material for aflatoxin extraction using CO₂-methanol. The percentage of aflatoxin recovery increased with CO₂-60% methanol and decreased with CO₂-100% methanol with an increase in the methanol/peanut meal ratio. One gram of peanut meal and 6 ml of 60% methanol were deposited in an extraction chamber (ca. 13 ml), pressurized with CO₂ to 3,000 psi at 50°C, and held for 15 min, followed by releasing and collecting the extraction medium. The extracted solution was applied to an affinity column for aflatoxin adsorption and to thin-layer chromatography for separation and fluorescence densitometry for component quantitation; an average of 97.6% of the aflatoxin was recovered. When this procedure and a commercialized immunochemical method were used for quantitation of aflatoxin in discolored peanut kernels collected from a commercial processing line, comparable results were observed.