OpenIDEO is an open innovation platform. Join our global community to solve big challenges for social good. Sign up, Login or Learn more

Linking small farmers to high-value markets for improved food safety and higher incomes in Kenya

We provide farmers access to technologies for reducing toxic fungal contamination and markets offering a premium for safe food.

Photo of Vivian Hoffmann

Written by


Fungal contaminants of food crops is a serious health problem in much of the developing world, due to climatic factors and rudimentary post-harvest practices. In addition, food safety is becoming an increasingly important precondition of market access. Smallholders who are unable to meet food safety standards will find themselves locked out of high-value agricultural output markets, leading to stagnating rural incomes and increased inequality. We propose to provide smallholder farmers in eastern Kenya, a global hotspot for the fungal contaminant aflatoxin, with access to effective pre-and post-harvest technologies for reducing contamination, and to link them to buyers willing to pay a premium for uncontaminated maize. Pilot work in Kenya has indicated significant interest among farmers in these technologies, particularly when a price premium for food safety is offered. This project would establish relationships between farmers in an aflatoxin-prone region and the largest maize miller in Kenya. If successful, this model is expected to lead to sustained improvements in both the incomes and health of farm families in eastern Kenya.


Smallholder farmers in Africa will benefit from access to technologies that allow them to reduce the contamination of their crops with a dangerous fungal toxin, and through access to a market for their produce that offers premium prices for safe food. Both incomes and the health of farm families will be positively affected by this project.


The project will be implemented in eastern Kenya, a global hotspot for toxic fungal contamination of maize.


  • Yes


  • I’ve worked in a sector related to my idea for over a year


  • Yes, for more than one year.


IFPRI, an international nonprofit organization, conducts research to provide policy solutions that reduce poverty and end hunger and malnutrition in an environmentally sustainable manner. Vivian Hoffmann, a Research Fellow at IFPRI, has been working on post-harvest issues in Kenya for 7 years.


This idea builds on previous IFPRI research, in which farmers were offered the opportunity to use a mobile maize dryer for a fee, and a subset were randomly selected to receive a premium price for aflatoxin-safe maize. In that study, the price premium was highly effective, increasing adoption of the dryer by 24% (on a base of 30%). Due logistical and funding constraints, however, the structure of the price premium was somewhat artificial: the premium was large (50% above the market price) and limited to a maximum of 45 kg, less than what farmers normally sell. The proposed project would test the impact of the actual premium offered by formal sector millers for high quality, safe maize, on farmers' adoption of aflatoxin control technologies. In addition to providing a more accurate picture of the impact of a premium price, the project will put in place market linkages that, if mutually beneficial to farmers and millers, will have a lasting positive impact on food safety and farmers’ incomes. This is a significant change from previous IFPRI work in food safety, which to date has focused on establishing proof of concept rather than catalyzing durable improvements in food markets


While there are other efforts to scale up aflatoxin control in the region, this project is the only one that includes a large-scale randomized evaluation of alternative approaches. The evaluation will be designed to generate new knowledge about how technologies with invisible benefits can be scaled up through markets. Food safety is one such benefit; nutritional value is another potential application. IFPRI has a long track record of conducting high-quality impact evaluations. Hoffmann has experience conducting randomized impact evaluations, including one on farmer adoption of aflatoxin control technologies in Kenya. She has established relationships with maize millers in Kenya through related research.


IFPRI and Wageningen University will provide overall direction and oversight, and work with several partners in Kenya. The Cereal Growers Association (CGA) will organize meetings farmer group meetings, at which both Aflasafe and mobile dryers are introduced to farmers. CGA will also connect maize aggregators working in Meru to buyers at Unga Ltd. IITA will provide technical expertise and training to farmer groups on the use of Aflasafe, and ACDI-VOCA will provide the same for mobile dryers.


In focus groups, many farmers expressed concern was about post-harvest losses due to insect damage. This led us to include hermetic storage bags as part of the package of technologies offered to farmers. Maize that is properly dried and stored in hermetic bags is protected from both insect pests and molds.


1) To what extent can the existing market premium for safe, high-quality maize generate adoption of aflatoxin control technologies among smallholder farmers? 2) What proportion of farmers are willing to adopt aflatoxin control practices in the absence of a premium? 3) Does adoption of aflatoxin control for marketed produce also improve practices applied to produce consumed by farm households? 4) How can targeted subsidies for aflatoxin control complement a market-based approach?

The objectives of this project are to 1) link farmers in Meru County, Kenya with entrepreneurs offering technologies (mobile dryers and biocontrol) to reduce toxic fungal contamination, and 2) establish direct commercial relationships between maize aggregators serving these farmers and formal sector maize millers, in order to motivate adoption of food safety technologies, boost farmer incomes, and improve health.

Food safety has become an important precondition for access to global food markets and increasingly for high-value domestic markets in developing countries (Ashraf, Gine and Karlan, 2009; Van Beuningen and Knorringa, 2009). At the same time, foodborne pathogens and toxins exact a significant health toll in developing countries (WHO, 2015), particularly among the poorest (Shephard, 2014; Moser and Hoffmann, 2015). Technologies to improve the safety of farm produce face several barriers to adoption. First, food safety is a hidden trait. Observation of many contaminants is possible using rapid tests, but costly relative to the value of farm produce. Inefficiencies in output markets characterized by multiple intermediaries exacerbate informational inefficiencies since information asymmetries arise at each transaction, preventing pass-through of incentives for food safety (Fafchamps et al., 2008).

Contamination with fungal toxins (mycotoxins) is a prominent food safety concern in tropical regions. Aflatoxin, a common mycotoxin in maize and groundnut, is is known to cause cancer and liver damage, and is suspected of inhibiting immune system function and contributing to childhood stunting (Gong et al., 2004; Strosnider et al., 2006; Turner et al., 2007; Hoffmann et al., 2015). Due to both ecological factors and poor post-harvest conditions, much of African produce is affected by aflatoxin, diminishing the region’s access to high-value export markets (Munasib and Roy, 2011). Food processing firms serving emerging domestic high-value markets are also increasingly testing for the contaminant.[1] 

Meru County in Kenya, the proposed site for this project, is known as a global aflatoxin hotspot. In 2010, considered by plant pathologists as an aflatoxin ‘outbreak’ year, 50% of maize samples collected at hammer mills contained in excess of 10 parts per billion (ppb), the maximum allowable level under Kenyan law; 10% were contaminated above 185 ppb, and the maximum level observed was over 4800 ppb, a level high enough to result in immediate sickness (data from Mutiga et al., 2014). Data collected from farmers’ stores in 2015 showed lower levels of contamination, but even in this “normal” year, 23% of samples exceeded the 10 ppb regulatory limit.

Two of the most effective tools available to combat aflatoxin in Kenya are adequate drying of maize, and the biocontrol product Aflasafe KE01. Mobile maize dryers with a capacity of 500 kg were tested by IFPRI in 2015 and found to reduce aflatoxin contamination in farmers’ stored maize 3 months later by 80% (Hoffmann and Jones, 2015). The dryer is now being offered, at limited scale, by local entrepreneurs with backstopping by the NGO ACDI-VOCA, at a price of 2,600 Kenyan shillings (approximately $26) per day. At typical starting moisture levels, the dryer can dry 2000 kg of maize per day. At this rate, the cost of drying is approximately 4.3% the value of maize.

Aflasafe is a biocontrol technology developed by scientists at the United States Department of Agriculture and adapted for Kenya by the International Institute for Tropical Agriculture (IITA). Aflasafe contains native strains of Aspergillus that do not produce toxins and outcompete those that do.  It is applied to the soil before flowering and protects crops throughout the growing cycle and storage period, with no impact on the overall level of fungal colonization or crop yields (Cotty et al., 2007). Aflatoxin biocontrol products have been successfully used on food crops in the United States for over 15 years, and in Nigeria for three years. The Kenyan variant, Aflasafe KE01, has been shown in farmer field trials to reduce aflatoxin contamination by between 93% and 99% (Bandyopadhyay et al., 2015). Aflasafe KE01 was approved by the Kenyan government for general use in June 2015, and domestic manufacturing is expected to begin in May of 2016, with an expected cost to farmers of $16 US per hectare.

For a farmer producing the median value of maize per acre in Meru, the cost of applying Aflasafe is approximately the same as that of using the mobile dryer. While Aflasafe is expected to be more effective at reducing aflatoxin than the dryer (leading to a 93-99% reduction compared with an 80% reduction) the disadvantage is that one must treat the entire maize field prior to harvest. If the harvest fails, or if a farmer generally has low yields, aflatoxin may not be a cost-effective choice. The most appropriate aflatoxin control technology for a given farmer will thus depend on his or her individual circumstances and risk tolerance.

IFPRI’s 2015 pilot of the mobile maize dryer showed that approximately 40% of farmers were willing to pay for the drying service after intensive educational efforts about the importance of avoiding aflatoxin. The proportion adopting the dryer was over 60% when market incentives for producing aflatoxin-safe grain were offered.

The proposed project would create such incentives by creating a direct market link between farmer groups in Meru and Kenya’s largest maize miller, Unga Ltd. A substantial gap exists between the spot market price of maize in the informal market, and that offered formal sector millers such as Unga. For example, on the same day in February 2015, Unga’s Eldoret plant was paying 2200 Kenyan Shillings (KSh) - approximately $22 US - for a 90 kg bag of maize, while the price at the local open air market was 1700 KSh. This premium exists as a result of the quality characteristics demanded by formal sector millers: maize must be dried at or below 13.5% moisture content; must conform to grading standards regarding the proportion of foreign matter, broken, damaged, and discolored kernels; and must contain total aflatoxins below the regulatory limit. Farmers are able to meet most of these criteria through adequate drying and removal of sub-standard grains and other particles. The exception is aflatoxin, which may be present without any visible sign of contamination. Unga has pledged to purchase maize that conforms to its quality and safety requirements from Meru farmers at a premium price.

By applying Aflasafe or using maize dryers, and storing maize in hermetic sacks, farmers in Meru would significantly reduce their risk of producing contaminated grain, reducing the exposure of their families to a dangerous fungal toxin. In addition, either investment would significantly increase farm incomes, based on available data on the price gap between the formal and informal sector.  Funding has been secured for researcher time to evaluate alternative business models to scale up aflatoxin control technologies in Kenya.  Additional funds from Amplify would cover the cost of the intervention itself.

[1] One example of industry self-regulation is the membership of 12 Kenyan maize processors in the voluntary Aflatoxin Proficiency Testing and Control for Africa program; see:



Join the conversation:

Photo of Joy Larson

Kudos for addressing food safety!

In relation to Isaiah's climate-related comment above, it seems like the need for sharing knowledge and technologies about best practices for food safety will become greater as increasing climate variability potentially introduces new or rare contaminants in food storage facilities. It seems like this model could be applied in other places, with other kinds of crops, or with other kinds of contaminants. Even under changing environmental conditions that come with climate variability.

Best of luck in the challenge!

Photo of William Lanier

To help the shortlisted ideas become the best that they can be I am interested to know…
What are the proposed "pre-and post-harvest technologies for reducing contamination"?
- Aflasafe and other biocontrol products must overcome the tendency of fungi to exchange DNA before they are an effective means to reduce aflatoxins
- Sun and heat will stop fungi, but the colorless aflatoxin that remains is extremely difficult to manually sort from surplus grain
- Depending on the crop, when low levels of fungi or insects enter typical sack jute or plastic sack warehouses, higher levels of aflatoxin may result (IARC, 2015)
- Periodic sack rotations are invasive and a labor intensive method of monitoring grain quality.

Hermetic PICs were developed for Cow Pea and other high value, high pest pressure situations and not surplus foods because...
The longer the grain is stored airtight before the seal is broken, the longer it would take for insect or grain metabolism to restore the airtight atmosphere.
Not even triple layers of plastic will stop the wear caused by removing daily portions, monitoring for chewing by rats, perforations by insects that bore in (George, 2011) and soon the bags are not airtight and cannot be used another season. Only when the plastic is recycled, are the acres of triple bags chemical free.
If airtight has not been maintained, residual fungi will increase and dormant insects awaken to cause PHL like aflatoxin (IARC, 2015) inside bags regardless of external controls like non-residual fumigation.
The hidden costs of building and maintaining roof and raised platforms that are required to mitigate the condensation caused by day and night temperatures are beyond the scope of this comment.

This OpenIDEO is excellent as it addresses the political hot topic of grading.
However the technical aspects suffer from being politically correct and do not address aflatoxin levels in surplus grain or as Dr. Cardwell (2015) presents, Why growers
"whose scale of operation is too small to be able to produce SAFE FOOD, are too small to farm maize (or any aflatoxin sensitive staples)" or afford “health care, school fees, retirement and supply National food security or surplus for exports” (peace-of-mind).

NeverIdle Mobile utility grain storage

Photo of Chioma Ume

Hi Vivian,

The Amplify team and our experts some feedback for you! 

Who will implement this idea? Where are they based? 

I think this project would benefit from co-design sessions with the farmers. Tap their local knowledge and ability to create work arounds. Education and commination is obviously a huge area that needs to be explored and design. What messages will resonate? How can the community be involved in educating and encouraging each other? Highlighting the need for storage bags is a great example of viewing the complete food journey and mapping the needs of each step.

How can the dryer be created to easily go from farm to farm?

Are there viable low-cost technologies that could scale out in the region? It might be useful to use technologies that have been tested in other regions and have been proven effective.

Looking forward to learning more! 

Photo of Dr Simon M Holland

Vivian, Seems you are doing great work all around to fixing the supply chain issues, by making sure quality and food safety.
We may look for collaboration in near future.

Photo of Nadia Firoz

Hi, interesting reading about your idea. Food safety is a issue of concern among small-holder farmers here in Bangladesh as well. We are also working towards ensuring food safety and connecting small-holders to high value premium markets. Good to come across similar initiatives across other parts of the globe. Keep up the good work !!!

Photo of Hifadhi Calm

Quite a big percentage of Kenyan farmers have been shying away from technology related solutions for their day to day use. It is a high time therefore for farmers both large and small scale to embrace technology to reap the benefits

Photo of Vivian Hoffmann

Farmers in our earlier study were very keen on the mobile maize dryer, which is a fairly simple and easy to understand technology. We'll see how they react to Aflasafe - this is a biocontrol product made from local strains of fungi that do not produce aflatoxin. IITA has been successful in getting farmers to participate in field trials of Aflasafe in Kenya, but I expect we'll need to invest some time explaining to farmers what it is and how it works in order to get widespread adoption.

Photo of Dorine Poelhekke

Great idea! I have one question: how do you guarantee a price premium for the uncontaminated maize?

Photo of Vivian Hoffmann

Hi Dorine,
We will connect farmers to millers that already offer a premium price for high-quality maize. One major miller has already pledged to provide a letter of intent to aggregators working with farmer groups enrolled in the project, indicating their commitment to purchase maize that conforms to their quality and safety specifications.  

Photo of Chioma Ume

Hi Vivian!
I notice you haven't filled in the answers to the new phase questions yet. Friendly reminder to do so before the phase ends next week. Remember that the 'full description' field won't be visible to any of your readers.


Photo of Vivian Hoffmann

Hi Chioma,
I can't seem to find the next phase questions on the website. Could you please direct me to these?

Photo of Chioma Ume

Hi Vivian!

If you go into your idea and choose the option 'Edit Contribution', you'll be able to see fields for the new questions. Let me know if you have any other questions!


Photo of Isaiah Etemo Muchilwa

Hi Vivian, this effort by IFPRI to avail small-scale farmers with technologies to mitigate fungal contaminants in foods is commendable. It is also nice that you correctly name climate as a key factor for pre-post harvest spoilage of foods, especially in the hot and humid equatorial tropics. All the major outbreaks of acute aflatoxicosis, with pandemic-scale fatalities that have put Kenya in the news globally, have occurred during El Niño years - a recurrent weather phenomenon associated with sea surface temperature anomalies in the equatorial pacific. Historically, El Niño in Kenya has been associated with intensification of the October-November-December rains, often extending to February and thereby coinciding with most of the maize harvest across the country. Achieving rapid and sufficient dehydration of foods is very difficult under these conditions and that is why I applaud your initiative to make artificial driers accessible to smallholder farmers. Here are a few insights to consider as you work to improve on this offering:
>Good interventions also require strategic (timely) application for efficacy. Availing drying facilities that are optimised only for "shelled" maize may not do enough to encourage early harvesting, as maize at physiological maturity still has to be pre-dried on cobs before shelling / threshing to limit kernel damage, and this can take months under foul weather - scaling up losses from rains, insects, fungi, birds, rodents and thieves <>. These spoilage agents are less active in the cooler regions of the world away from the equatorial tropics, making natural field dry-down of crops less risky and favouring the late deployment of shelled maize driers for combine-harvested crops. For smallholder farmers in the tropics who hand-harvest their maize, artificial cob-drying at physiological maturity is feasible and more strategic, and the challenge for mainstream engineering is just to develop appropriate technologies for this purpose, one of the goals of my own research.
>Co-occurrence of aflatoxins and fumonisins (both potential carcinogens) is common across Kenya. Although Aflasafe is showing promise as a mitigant against aflatoxins, we should take into account the fact that this intervention does not guarantee 100% efficacy since it relies on the cooperation of the same unpredictable skies that spoil foods, to avail sufficient precipitation at the critical time of application just before flowering (not flexible). In addition, there are several other known contaminants associated with fungi (more yet to be discovered) and taking out just one does not necessarily render mouldy foods safe to eat. Even though mycotoxins may present in foods that are not visibly contaminated, "mouldy" kernel counts feature prominently in national and international maize grading standards, regulations that will most likely dictate access to the premium markets that you are targeting.  Prevention is key and the ultimate goal should be to keep moulds off our foods. Strategic harvesting and drying can achieve this for us.
It will be nice to see this project succeed and sustain to impact on livelihoods across Kenya. 
All the best and kind regards

Photo of Vivian Hoffmann

Dear Isaiah,
Thank you for your feedback and encouragement. I agree with your comment that providing farmers with a way to dry their maize before it is shelled would be ideal. Indeed, the mobile dryer could be used this way, it would just require more time.  Farmers could do initial drying on the cob immediately after harvest, then shell, then dry the maize kernels down the rest of the way to 13.5%. I think it's worth exploring models through which this could be affordable; perhaps if dryers are purchased at the farmer group level, this could work. If dryer time is offered to farmers by an entrepreneur, I fear this will be too expensive for most farmers.
Regarding Aflasafe - absolutely, this only addresses one mycotoxin, and might be most appropriate in regions with high pre-harvest aflatoxin, but not so much fumonisin, and decent drying conditions. For places where humid post-harvest conditions are the root of the problem, dryers are probably a better solution.
All the best,