Experiment Description

Aflatoxin Research

Aflatoxins produced by the Aspergillus fungus contaminate millions of pounds of peanut and maize crops each year.  They are especially widespread in developing countries such as Guatemala and Kenya where standards for Food and Drug safety are significantly lower than those in the US and Europe.  Peanut farmers in Guatemala are prevented from exporting the vast majority of their crops to sell in the US and Europe due to high levels of aflatoxins, depriving them of a much needed source of income.  In addition, aflatoxin-containing peanuts which remain in developing countries can cause serious long term health problems for people who are unknowingly exposed, and outbreaks in Kenya and surrounding countries have led to several hundred deaths.  Specifically, aflatoxins are known to suppress the immune system and increase the risk of liver cancer, HIV, and malaria. 

Test Objectives

The purpose of this research trip is to quantitatively measure the aflatoxin-reduction capabilities of two low-cost technologies developed by The Full Belly Project:
  1. Universal Nut Sheller (UNS) – A hand-operated concrete device which is used to remove the shells of peanuts and other nuts.   Since the aflatoxin-producing fungus Aspergillus Flavus tends to grow predominantly on the outside of the peanut shells, it is believed that the UNS can reduce cross-contamination between peanut shells.  During the manual shelling process, typically the sheller mixes the shells and kernels by hand, so any fungi growing on the outside of the shell is exposed to the kernels for consumption.  In addition, this exposes the manual sheller’s hands to the aflatoxin, which is also a health hazard because the toxin can be absorbed through the skin.   On the other hand, the UNS breaks the peanut shells inside of the concrete machine and the loose shells can be blown away by an electric fan, minimizing the kernel/shell mixing and the human exposure during the process.  However, the amount of aflatoxin-reduction has not been tested yet, and preliminary test data will be collected during this experiment. 
  2. UV Scanner Box – A wooden box with a UV light inside, this device is used to screen unshelled peanut samples for fungi contamination.  It is known that Aspergillus Flavus fluoresces under 365 nm UV light, while the normal outside of an uncontaminated peanut shell appears opaque.  The machine requires 4 people to operate, with 2 people loading/unloading peanut trays and 2 people looking in through portals to pick out the glowing peanuts.  The streamlined assembly-line style human-powered conveyor belt is designed to be both simple and efficient, so that a team of 4 workers can sort hundreds of pounds of peanuts per day.  A youtube video demonstration of this procedure can be found on the videos page. 


USAID Guide to Peanut Production on the Rupunini Savannas

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