16/08/2026
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WHEN Bernadette Wangu Syakayuwa heard stories about market vendors and smallholder farmers watching their fresh produce rot before reaching buyers, she resolved to develop an innovation that would enable people in rural communities to preserve surplus crops and unlock new trade opportunities.
She developed an automated, temperature-controlled food dehydrator, a low-power agro-processing unit that uses a digital thermostat and an Arduino microcontroller to transform perishable fruits, vegetables, and meat into storable, tradable commodities.
Bernadette, who is a learner at ๐๐๐ฎ๐ซ๐ ๐๐ข๐ซ๐ฅ๐ฌโ ๐๐๐๐จ๐ง๐๐๐ซ๐ฒ ๐๐๐ก๐จ๐จ๐ฅ in Kasama, shared that she was inspired to develop the innovation after hearing from family and mentors about the daily struggles of market vendors and smallholder farmers who lose up to 40 percent of their harvests to post-harvest spoilage. She was particularly moved by watching her own family lose crops during market gluts, when oversupply caused prices to crash and tonnes of tomatoes, mangoes, and leafy greens perished for want of any preservation method.
"I wanted to come up with something that could help farmers and vendors turn their surplus into inventory before it goes to waste," she said.
She says that the dehydrator automatically maintains precise drying temperatures while small fans drive continuous airflow.
"If you load fresh mangoes, the machine maintains temperatures between 50 and 60 degrees Celsius and dries them to below 10 percent moisture within 10 hours, producing chewy, deep-yellow slices with concentrated flavour that can be stored for 12 to 18 months. For leafy greens like r**e, it takes just six hours to achieve a crisp, bright green product that retains its nutrients," she says.
The innovation was tested over 14 days on five different food types, r**e leaves, mango slices, banana slices, orange slices, and beef strips, successfully reducing moisture to preservation levels while using less than 1.8 kilowatt-hours per cycle, less than baking a single cake in an electric oven (a standard oven uses 2-3 kWh per hour, so 45 minutes of baking already exceeds one dehydrator cycle).
Unlike conventional sun drying, which takes two to four days and leaves food exposed to flies, dust, and sudden rain, Bernadette's dehydrator runs inside a sealed cabinet and completes the process overnight. Sun-dried produce often suffers uneven drying and mould, giving it a shelf life of only three to six months, whereas her machine delivers uniform results that stay fresh for 12 to 18 months when properly stored. The precise temperature control also preserves vitamins and colour that open-air heat and UV exposure often degrade, meaning the dried goods look good enough to package for supermarkets and export. And because the timer and thermostat handle the work automatically, a vendor can load the trays in the evening and sell fresh produce at market during the day while the machine builds dried inventory overnight.
The project has been entered into the 98th Zambia Agricultural and Commercial Show (ZACS) 2026, where it competes under the theme "Fostering Trade and Investment." A full Bill of Quantities in her report confirms the unit can be built for K2,895 using locally available materials.
However, Bernadette acknowledges that the innovation faces real-world hurdles. The prototype requires electricity, whether from the grid, solar panels, or a battery-inverter system, which remains out of reach in some rural areas. At K2,895 for the full smart configuration, the upfront cost is also beyond the means of the poorest subsistence farmers, meaning cooperative ownership or microfinance would be essential for widescale adoption.
The prototype machine's batch capacity is another constraint, holding less 1 kilogram of fresh produce per cycle, meaning larger harvests would need multiple units or scaled-up chambers. She also notes that troubleshooting the Arduino sensors and relays requires basic electronics knowledge, and the control board must be protected from dust and moisture if the cabinet seal is compromised.
To scale the prototype into an investable enterprise, Bernadette has already mapped out a clear growth path. She envisions increasing the cabinet size to accommodate 20 to 30 kilograms per batch using the same locally available marine plywood, upgrading to multiple heating zones with independent thermostats, and installing larger fans for deeper tray stacks. Modular four-chamber racks would allow cooperatives to dry different products simultaneously, meat at 40 degrees Celsius and mangoes at 55 degrees Celsius, without cross-contamination, all running off a shared solar power bus. She also plans to partner with local carpentry workshops to prefabricate cabinet shells, source components in bulk to cut costs by 25 to 30 percent, and pre-programme Arduino profiles so users simply select a food type rather than manually adjusting settings.
"These are not impossible barriers," she says. "They are exactly why this project needs partners, to bring down costs through bulk manufacturing, to train village technicians, and to connect farmers to the solar power they already need for so many things."
She now hopes to attract investment to establish a local manufacturing workshop capable of producing the dehydrators on a larger scale, develop cooperative drying centres in rural markets, and build a dried-food value chain that links smallholder farmers to urban supermarkets and cross-border traders.
