Feed the Future
This project is part of the U.S. Government's global hunger and food security initiative.

Exploring Storage and Drying Solutions for Aflatoxin Prevention

We sat down with Sophie Walker, Chief of Party of the AflaSTOP project. Based in Kenya, AflaSTOP is investigating storage devices that will prevent the growth of aflatoxin-producing mold during storage and exploring drying technologies that will help farmers reduce grain moisture from current levels at 15-18 percent to a safer 13.5 percent. AflaSTOP intends to commercialize the most promising of these technologies in order to scale adoption.

 What devices has the program been testing and which seem the most promising for commercialization?

AflaSTOP has been testing a variety of storage and drying devices to evaluate whether a technology exists that can prepare and store grain to impede further aflatoxin contamination on the smallholder farm. We have four different devices that we are trying to commercialize currently.


At the end of our trial, we had results that proved that three of our storage devices were highly effective.

The GrainPro Grain Safe II is made out of patented plastic technology and placed on a custom made frame.


GrainPro Grain Safe II: This bag is produced by GrainPro and imported into the country duty free. Current storage capacity ranges from 800-1,300 kg. They will soon be introducing a 500kg bag. The estimated cost for the frame and bulk bag is around $260.

These metal silos are produced locally.

Metal Silo: The silos are made out of aluminum and produced by local artisans. They are placed on a pallet and size ranges from 200-1,000kg. Estimated cost is $144.

Purdue Improved Cowpea Storage (PICS) Bag: This bag is a triple layer plastic bag introduced to West Africa by Purdue University and currently manufactured in Kenya by Bell Industries. This bag requires placement on a pallet. Capacity ranges 90-100kg with costs estimated at $2.80 per bag.


As for drying technology, the shallow bed dryer shows the most promise. It is a completely new device that has never gone to market. The basic configuration of this mechanical dryer is a furnace, a heat exchanger and a supply of air (provided by fan). The heat from the furnace moves through the heat exchanger and through the raised bed that contains the grain.

Shallow bed dryers show a lot of promise, but have not yet reached the market.

Do drying and storage interventions need to be implemented together? In other words, can you have one without the other?
In my opinion, you can’t separate them. If you store wet maize, regardless of aflatoxin, it goes bad anyway.
What are the next steps?
In terms of programming, we have identified the devices that work in controlled conditions; we are testing the three storage devices to see if they will work with farmers. We have tested and tested the dryer so we know that it works.

We can’t wait for the results of on-farm storage trials because it takes eight months, so we are developing commercialization strategies for all devices based on our knowledge now. Next year, we will add in the aflatoxin overview, to see if that changes our commercialization strategy.
What is the goal of your work?
The goal of my work right now is mass adoption of these storage and drying devices by smallholder farmers, either as an investment on farm or a service that they buy in to. We need to ask ourselves how we can provide the knowledge to private sector companies working in this area so they can drive their supply chains down to small agridealers.