Preventing aflatoxins by distributing low-cost DryCards to test food dryness

Summary

The DryCard is a simple, low-cost tool that measures food dryness. This technology enables users to determine whether their product is dry enough to prevent mould growth and mycotoxin production. In partnership with the Feed the Future Innovation Lab for Horticulture at the University of California, Davis, a Rwandan startup company called Development Solutions Consulting has trained Rwandan youth and women to manufacture Drycards locally. So far, the startup has distributed 7,000 DryCards to farmers. 

Challenge

Drying is a technique used to preserve harvested products, but knowing when products are dry enough can be difficult. When products are not properly dried they can grow mould and produce harmful mycotoxins such as aflatoxins. Common methods to test for dryness such as biting, touching, or sniffing the product are unreliable and inaccurate. Electronic devices that measure moisture or humidity are often too expensive and difficult to use.

Contamination of dry foods by mould is a major global problem that contributes to both food security challenges and disease transmission. It is estimated that mould affects approximately 25 per cent of the world’s crops, with aflatoxins, a type of toxin produced by mould, being responsible for health problems such as acute poisoning, liver cancer and stunting.

Aflatoxins are a particular problem in Africa, where commodities are stored under hot, humid conditions. Contamination of staple crops such as maize and sorghum directly reduces the availability of food.  Producers may earn less because of product rejection, reduced market value or lack of access to formal markets and higher-value international trade. Lower farmer incomes means less ability to purchase food for the family, which translates to higher levels of hunger and poverty. 

It is estimated that the continent loses between EUR 400 and EUR 600 million a year in export earnings, and that about 26,000 Africans living south of the Sahara die of liver cancer every year through chronic aflatoxin exposure. 

If left unaddressed, the problem of mould contamination will continue to present a formidable obstacle to achieve the first three Sustainable Development Goals of no poverty, zero hunger and good health and wellbeing.

Solution

Post-harvest toxin production can be prevented by ensuring that products are sufficiently dried before storage. A major challenge, especially for smallholder farmers, is the lack of access to testing and certification facilities. Although there are electronic moisture meters that can measure humidity, available instruments can be too expensive for smallholder farmers, and most of these tools require regular calibration.

Retailing at below US$1, the DryCard is an inexpensive device developed by University of California, Davis for determining if dried food is dry enough to prevent mould growth during storage. The tool is intended for smallholder farmers who cannot afford the expensive moisture meters in the market.

To use the DryCard, a farmer simply places the DryCard and a sample of the dried product in an airtight container such as a sealed plastic bag or jar. After a few minutes, the card’s indicator, a strip of cobalt chloride, will change color based on the equilibrium relative humidity. The farmer then matches the color of the strip with the corresponding scale on the card. A pink color on the strip means the product is too wet for safe storage, while blue or mauve means it is adequately dried.

Training entrepreneurs can easily scale the DryCard to manufacture and distribute locally. The DryCard can be used for up to two years. Due to its low cost, it is also easily replaceable if an older DryCard no longer works well.

The solution’s developers have held discussions with relevant government departments including the Ministry of Agriculture of Rwanda and the Rwanda Standards Board. The USAID-funded Cultivating New Frontiers in Agriculture Hinga Weze Activity has agreed to provide financial support to disseminate the technology, and the World Food Programme procured 5,000 Drycards for its Farm-to-Market Program.

Results

In partnership with a local startup, Development Solutions Consulting Ltd, the solution developers have distributed over 7,000 DryCards to farmers in Rwanda. Five Rwandan partners have also been trained to manufacture DryCards and provide technical support to users. Currently, the DryCard is available for distribution in 13 countries.

About 200 agricultural extension agents from the Ministry of Agriculture, cooperatives and some non-governmental organizations have been trained on the use of the DryCard to enable them to disseminate the information to smallholder farmers.

Other public information outreach initiatives have included participation in the national agricultural show and media appearances. Instructions for the proper use of the card have been translated into a number of local languages. Because DryCard is manufactured locally, the technology is accessible and easily adopted. 

 Lessons Learned/Potential for replication

A key factor for success is buy-in from the Rwandan government, as its institutions are crucial to the successful distribution of the technology. Other partners that should be engaged to support distribution include large-scale buyers such as cooperatives, NGOs and public projects. 

Bundling the DryCard with other “dry chain” equipment such as hermetic crop storage bags adds value to farmers and drives overall adoption of good practices in post-harvest management. The dry chain refers to the practice of keeping a product hermetically sealed and below 65 percent relative humidity during storage and transportation.        

There is still a considerable lack of awareness about aflatoxins. Investing in public education and communication, especially targeting the poor, must be a priority for countries in the fight against aflatoxins. 

Next Steps

The solution provider aims to reach 50,000 farmers by 2022. This will be achieved by training 15 master trainers who are expected to reach 150 farmers as service providers. Each of these service providers will in turn be expected to reach 500 farmers.

Because it is affordable and can be manufactured locally, DryCard offers great potential for replication in other rural areas. Although it is being tested in Rwanda, it could be an effective tool for managing post-harvest losses throughout all of Africa.