A technology intended to feed astronauts on Mars is being adapted to improve production on instant porridges and other ready-to-use products in Africa.
NASA commissioned Purdue University researchers to develop a scaled-down version of an extruder that could be used to process various grains during a mission on Mars.
The device uses friction to heat and cook soybeans and then separates the oil creating a rope-like substance that can be dried to make flour or combined with other products to make pastas and snacks.
“NASA wanted a way to process food on Mars because it is so expensive to ship food there, something like $200,000 per kilogram,” said Martin Okos, a professor of agricultural and biological engineering and one of the project’s leaders.
He added: “The biggest challenge we faced was scaling down, but we developed an extruder that is down to about 60 pounds per hour. NASA would like an extruder to be 100 times smaller, however more research is needed to reach that goal.”
Before the extruder makes its debut on the red planet, however, it is being used to improve food production capacity in Niger, Senegal and Kenya.
After working on the NASA prototype, Okos and graduate student Amudhan Ponrajan modified the extruder to work with other types of grains, including corn, rice, wheat, chickpeas and lentils, which are more widely grown in developing countries.
Those grains can be milled/ground, mixed with water and pushed through the extruder, which uses a screw to force the product through a channel where friction heats and cooks the grain. The rope-like product that results can be dried and ground into flour that, when mixed with water, results in an instant porridge.
Many traditional African porridges made from those grains can be labour-intensive to make. In urban areas, consumers are looking for more convenient alternatives, and the only ones in market are imported and expensive. The extruded grain products can be dried and packaged as “just-add-water” versions of traditional meals.
In West African urban areas, labour-intensive efforts to make products like couscous could be drastically shortened. It can take a crew of 10 women in Niger an entire day to create 30 kilograms of couscous using current methods. With the extruder, the same crew could make 300 kilograms in a day.
The modified extruder was designed to be relatively inexpensive. Large-scale extruders in US production facilities today cost up to $200,000 and can process hundreds of kilograms per hour. The Purdue-modified extruder can produce 35 kilograms per hour, but it costs only $20,000.