CEE Team Works to Minimize Postharvest Food Loss
By Leanne Lucas
The postharvest loss of staple crops around the world has global implications in areas such as food security, malnutrition, poverty, and food waste. Researchers within CEE are working with the ADM Institute for the Prevention of Postharvest Loss to develop practical strategies to combat those losses. The Archer Daniels Midland Company established the Institute in January of 2011 with a $10 million grant to the University of Illinois at Urbana-Champaign.
Associate Professor Ximing Cai is leading the CEE team, which includes faculty from construction materials, construction management, environmental engineering and science, geotechnical engineering, and structures. They will investigate optimal engineering solutions and infrastructure investment required to minimize postharvest loss.
“We believe people from different areas of civil engineering can work together to utilize traditional civil engineering tools to address the problem of postharvest food loss,” said Cai. “This interdisciplinary collaboration will provide benefits and insights that result in better solutions.”
Although losses vary greatly by crop, country and climatic region, Cai said estimates of postharvest loss range anywhere from 35 to 50 percent around the world. According to a 2011 United Nations Food and Agricultural Organization (FAO) study, “Roughly one-third of food produced for human consumption is lost or wasted globally, which amounts to about 1.3 billion tons per year.” An example given in an FAO/World Bank report stated that “[t]he value of postharvest grain losses in sub-Saharan Africa [are estimated] at around $4 billion a year. ... This lost food could meet the minimum annual food requirements of at least 48 million people.”
These losses also contribute to higher food costs and impact environmental degradation and climate change. Water, land, human labor and non-renewable resources such as energy and fertilizer are used to produce, process, handle and transport food that no one consumes.
“What if we could reduce those losses by half?” Cai said. “How would that affect, for example, water sustainability?”
In many regions, agricultural water use has been increasing while the water available for use has been declining because of the climate, Cai said.
“Agricultural engineers have worked to develop effective irrigation systems to help farmers save water, but no matter what we do, we need a certain amount of water to grow the crops,” he said. “In some places, after harvest, a third of the crop is lost. If we could reduce that loss by half, then we could produce more and use less water, less land, less energy, etc.”
The project will focus on postharvest loss mitigation in India. The team is divided into four sub-groups, each working on a different component of the project. Professor Wen-Tso Liu, of the environmental engineering and science group, and Assistant Professor John Popovics, of construction materials, will develop bio-sensors to monitor grain degradation in stockpiles.
“Wen-Tso will evaluate the mechanisms of degradation from a biological point of view,” said Popovics. “CO2 is one indicator [commonly the result of respiration by insects and microbial life forms such as mold and fungus], but we both believe that there are other indicators that might be better than carbon dioxide — possibly moisture, temperature, or some other indicator. My job is to develop a sensing system to monitor whatever indicates the presence of that degradation. The system has to be robust, cost-effective and rugged, to be used in situ.”
Popovics is also working with Assistant Professor Paramita Mondal, of construction materials, to look at materials that can be used to build or repair storage facilities.
“There seems to be some emphasis from the Indian government to build more warehouses or repair the old ones,” said Mondal, “but what seems to be most interesting for us at this point is to work at the village or on-farm storage level. Right now that is very limited. Storage facilities are made of adobe or wood, and sometimes they just pile the grain on the ground or dig a pit and pour it in. It’s very makeshift, it doesn’t last long, and it doesn’t prevent any of the degradation mechanisms John was talking about,” she continued. “We are thinking about how to use locally available material, so that the people have ready access to it. And construction of storage facilities should not be difficult, so farmers can hire villagers or do it themselves.”
Materials being considered include rice husks, a waste product from rice production that can be burned to an ash that has cementing capacities, natural fibers such as jute, or recycled fiber from the paper industry.
Professor Youssef Hashash, of the geotechnical engineering group, is working with Associate Professor Khaled El-Rayes, of construction management, on grain transport and storage.
“We need to understand two things,” said Hashash. “First, what goes on in the process of moving the product from the farm to storage? What is the mechanical aspect of this process? How do they carry it, put it in a sack, put it in a truck, stack it in a warehouse, bring it back out, and distribute it? Can we improve the conveyance systems that are being used? Second, how are the logistics of storage managed? How is it organized?”
Like all the members of the team, Hashash emphasized the importance of visiting India to further understand the needs. “Visiting the area is a very important component of this because farming practices are very different from, say, farming practices in the United States. The systems in place to collect, consolidate, and redistribute the harvest are really quite different. It’s significantly less industrialized. Taking solutions that may work here or in other countries is not the approach that will work best.”
Finally, Professor Praveen Kumar, of the environmental hydrology and hydraulic engineering group, is working with Cai to develop a model which takes the information that will be gathered by all the different sources and provides scenarios that will enable the farmers and decision-makers to take appropriate actions to mitigate postharvest loss.
“To what extent can we integrate technologies across the entire postharvest supply chain to find the optimal way to manage the loss?” Kumar asked.
Cai said he believes the project will provide some unique opportunities for undergraduate and graduate students.
“CEE has just launched a new program, Sustainable and Resilient Infrastructure Systems. It hosts people from different traditional CEE areas to work together for more efficient infrastructure systems design. So this project provides an example for the new program to work on in the future.
All the team members agree that the issue of postharvest food loss is a non-traditional area for civil engineers.
“I’m operating outside of my comfort zone,” said Popovics, “in as far as working on agricultural issues. But postharvest loss is a huge issue, and we have to figure out where we can apply our knowledge.”
Hashash said, “It’s a very different project for civil engineers, but it is within the realm of a new direction that we are going, which is systems and sustainable solutions. When you view the problem as a system, not as individual components, our combined expertise will allow us to address the problem. It’s part of our struggle to achieve a sustainable lifestyle, and we have a skill set that we can apply. We hope to be leaders in a new area.”
Photo: istockphoto.com/David Mathies