Mixing maize with amaranth during storage can reduce weevil infestation by up to 75 per cent, scientists have found out.
"Storing maize mixed with amaranth will reduce the interstitial space between kernels, overall void volume, and therefore, total oxygen available to weevils," said Dr Carl Bern of Iowa State University, US.
In addition to limiting oxygen availability, filling the interstitial spaces leads to restricted movement of the weevils, which in turn denies them access to kernels, making reproduction difficult, Dr Bern, and other scientists from the Department of Agricultural and Biosystems Engineering at the university explained.
The combination of reduced access to maize and decreased oxygen results in reduced infestation. The technique was among others discussed recently at a global forum on post-harvest loss in Italy.
Millions of farmers in developing countries, and some in industrialised nations, are in the thick of runaway post-harvest loss, a crisis now described by the experts as "a perfect storm facing humanity".
About 1.3 billion tonnes, or one third of all food produced for human consumption, is lost before it reaches the market or the consumer every year around the globe, a figure which is enough to feed the total number of undernourished people globally. In Sub-Saharan Africa, home to over 230 million people suffering from chronic undernourishment, 30-50 per cent of food produced is lost at various points along the value chain.
SHORTAGE OF TECHNOLOGY
This 'perfect storm' is what drew the 262 delegates - business leaders, government officials, non-state actors, academics and scientists from 62 countries around the globe - to the first international congress on post-harvest loss prevention, held in Rome, the seat of United Nation's Food Agricultural Organisation and World Food Organisation early in the month.
The congress was held to lay strategies for combating the waste, which is reducing food security, cutting farm incomes, raising prices and endangering lives.
"With the exponential rise in population, man is facing the perfect storm. And food loss is at the heart of this storm. Luckily, the world is beginning to take note and we have the capacity to weather this storm," Toby Peters, a visiting professor in Power and Cold Economy at the University of Birmingham, UK, said, setting the tone of the congress held between October 4 and 7.
Prof Peters is the co-founder of Dearman, which has pioneered a cold chain of temperature controlled vehicles and warehouses that reduce spoilage and quality degradation by chilling and freezing products using liquid air.
"Cooling air is more efficient than the batteries. What we need is not just a cold chain, but a clean cold chain," he argued.
A big shortage of agricultural scientists to keep pace with the innovations needed to produce enough food was also stressed as a key challenge.
"It is no longer how much we produce, but how much that reaches the consumer," Joe Taets, the President of the Archer Daniels Midland Company's agricultural services business unit said.
The American global food processing and commodities trading corporation's donation of $10 million (Sh1.03 billion) in 2011 went into the setting up the ADM Institute for the Prevention of Postharvest Loss at the University of Illinois at Urbana-Champaign, the convener of the congress.
A key contributor to post-harvest loss is the skewed nature of the gender divide with women producing 80 per cent of world's food. Their low access to capital robs them the capacity to fight food loss.
"There is need to increase the participation of men to reduce post-harvest loss. Now is the time to come together and build a coalition against post-harvest loss," said Dr Judith Rodin, the President of the Rockefeller Foundation, a philanthropic organisation with programmes that impart post-harvest storage tips in Sub-Saharan Africa, including Kenya.
Dr Rodin noted with the changing weather patterns, there was need to build a greater resilience for the smallholder farmer to absorb the shocks and stress and connect them more to the market.
"We need more resources from business leaders to pump into technology and innovation," she told the congress that was supported by the Bill and Melinda Gates Foundation, the Rockefeller Foundation, John Deere, FAO Save Food initiative and USAID's Feed the Future.
Daniel Gustafson, FAO deputy director-general, called on farmers in the industrialised and developing countries to work together.
"We need to look at the smallholder farmers as business people. The private sector too creates markets that will be absolutely necessary in combating post-harvest loss," said Dr Ertharin Cousin, the executive director of WFP.
CD Glin, the associate director for Africa at the Rockefeller Foundation, called for more research into the existing loss-reducing technologies to shore up the world's capacity to significantly cut post-harvest loss.
"Smallholder farmers need a safe, affordable and effective solution," said Dr Phillipe Villers, the President of Grainpro USA, a firm that has developed a low cost, reusable hermetic storage bag for subsistence farmers.
Dr Villers said the bag, called SGB Farm, can help preserve the freshness and quality of commodities such as maize, wheat, soybeans, rice and cassava. He said the bags did not require fumigation with chemicals and could keep grain safe for up to 12 months or longer.
Piloted in Guatemala, GrainPro now sells the bags in Kenya, Ethiopia, Ivory Coast India, Costa Rica, Brazil and Mexico.
The company has also developed a Solar Bubble Dryer together with Hoheneim University in Germany and the non-profit International Rice Research Institute. As the name suggests, the dryer uses solar and a bubble enclosure to dry commodities, while keeping it safe from impurities.
Rwanda, the tiny central African nation, was singled out for praise as the best practice case study on post-harvest loss prevention in Africa, having cut the losses from 30 per cent in 2011 to 15 per cent in 2015.
Kenya came under scrutiny for what was described as unacceptably high levels of aflatoxin infestation. The congress heard that in some areas, up to 65 per cent of flour is unfit for consumption. To mitigate this situation, mobile solar dryers were billed as an important incentive for producing aflatoxin-safe food. The need to pay farmers premium prices for aflatoxin-safe maize was also broached.
"Aflatoxin has been a major barrier to farmers seeking the international market because of the stringent standards. Farmers (in Kenya and other developing countries) are willing to use technologies to cut post-harvest loss. We need to pull together; working together works," Mr Michael Scuse, the undersecretary for Farm and Foreign Agriculture Services at the US Department of Agriculture told the gathering.
Kenya's handling of its vegetables was also in the spotlight, with Dr Willis Owino of Jomo Keyattta University of Agriculture and Technology, reporting that up to 69 per cent of amaranth was lost because of poor handling.
"Traditional storage methods can only guarantee selling food shortly after harvesting only to buy it back at a higher price, aiding a vicious cycle of poverty," said Ms Alexandra Spieldoch of Compatible Technology International.
Ms Spieldoch is working on a project to reduce grain loss through the introduction of mechanised pearl millet threshing tools in Senegal.
Aflatoxin is a major post-harvest maize disease, which eats into earnings of farmers.
Millers reject maize that has high moisture content to avoid losses resulting from aflatoxin.
Sun drying is the method which most grain farmers use to dry their produce, but it does not produce good results.
Electric dryers, which have capacity to dry up to nine tonnes in two-and-a-half hours cutting the moisture content from 20 to needed 13.5 per cent, costs up to Sh6.5m.
Leaving mature maize on the farm to dry exposes the harvest to diseases and pests.