The role of manual sorting of raw peanuts to minimize exposure to aflatoxin-contaminated peanuts
Keywords:
Aflatoxin, manual sorting, peanut kernels,, ZambiaAbstract
The occurrence of toxic concentrations of aflatoxin in peanuts requires appropriate intervention. In countries such as Zambia with poor implementation of existing regulatory standards, consumer action can minimize risk of exposure. The current study evaluated the significance manual removal of shriveled, externally-discolored, misshapen, mechanically-damaged and insect-damaged kernels to minimize the baseline aflatoxin content in peanut samples. One hundred and two (102) aflatoxin-contaminated samples of raw peanuts each weighing 1 kg were collected. Each sample was sub-divided into two 500 g- subsamples of which one was manually sorted to remove contaminated kernels before the paired samples were each tested for total aflatoxin content. Results of a paired sample t-test showed an average of 56% reduction in mean total aflatoxin content from an initial 10.4 µg/kg (range of 5.2 to 18 µg/kg). Although manual sorting can be tedious for large lots and may not remove contaminated but visually sound kernels, careful sorting of raw kernels prior to consumption or processing into other peanut products is an essential step to minimize aflatoxin content. Responsible peanut consumers should embrace this practice to minimize aflatoxin content in their food.
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