Interview with Dr. H. N. Cheng: Reimagining the Role of Chemistry in Food Security
The field of agriculture has been complete reshaped by the chemical sciences. Starting in the 1950’s, the synthetic fertilizers and pesticides introduced as part of the “Green Revolution” helped food production to skyrocket. But chemists will need to find new areas to innovate to meet the needs of a growing world population in the 21st century. The next wave of food system advancements may come from chemists studying the nutrients in our foods, the packaging we use for storage, and the effects of climate change on soil and food chemistry.
Dr. H. N. Cheng has thought a lot about chemistry’s role in food security in the coming years. In addition to his research in polymer green chemistry and biobased materials, Cheng has worked closely with the USDA and served as ACS President in 2021. This experience provides him with a broad perspective on the field of chemistry and the food sciences. This is manifest in his passion in agricultural innovations, including precision agriculture, which is the use of GPS, sensor, and drone technology to increase crop performance.
Dr. Cheng will present at the “Zero Hunger Summit,” organized by the American Chemical Society. This free online conference, taking place December 5-8 (11 AM -1 PM EST), will explore how chemistry and engineering can contribute to the U.N. Sustainable Development Goal of “Zero Hunger.” Register for the Zero Hunger Summit.
This interview was edited for clarity and brevity.
Many focus on economics, politics, or supply chains when considering solutions to world hunger. Does chemistry play a role as well?
Yes. Just see the example of the Green Revolution. In 70 years, we have tripled the amount of agricultural output per year, using the same acreage. The Green Revolution involved a number of factors to achieve the higher-yielding crops, including the use of fertilizer, and agrochemicals, such as pesticides, insecticides, and fungicides. You can see chemistry in most of these things. Chemistry can do something.
Today, “Green Revolution” innovations are being applied in new ways with the with help of smart technologies in “precision agriculture”. Can these help overcome the challenges we face concerning food production and availability?
That’s right. We can literally double again - double the amount of agriculture outputs with precision agriculture. The population of the world is going to reach, I think, 9.6 billion in 2050. We need to have food to feed people, and I think precision agriculture has that possibility.
Of course, there are other factors involved, like minimizing food waste. Right now, one-third of the food from agriculture is wasted before it reaches the table, and one-third of the food on the table is not eaten in America. In America, we are blessed with a surplus of food. Many countries are not that fortunate. The idea here is to minimize the waste both from agriculture and from the home.
People may think only specific areas of chemistry, such as agrochemistry, are related to food. Your research into biobased or biodegradable materials for food packaging is an example of how other areas of chemistry can address this problem. Can you explain that research?
There has almost been a step change in the food packaging area in the past few years. Look at the goods in the supermarket. Most are good for a month, sometimes two months. Now you can ship a package from South Africa to America because there is better technology and better understanding what causes foods to be spoiled.
Most food packaging today is still based on synthetic plastics. The trouble is plastics are built to last forever. You have landfills filled with plastics. The microplastics are found everywhere, in clean water supplies, and in sewage. It gets into humans.
The idea now is we use biodegradable and biobased materials, which break down so that they don’t accumulate. I’ve written a review article on using biobased materials in food packaging covering five different approaches: the use of plant-based materials, composites, surface modification, incorporation of essential oils as a natural anti-microbial, and the use of nanomaterials to strengthen natural materials.
A good example of a biomaterial useful for food applications is cellulose esters. Cellulose esters have very good physical properties. The material makes a nice film, and it is biodegradable. My work has shown that you can even incorporate essential oils inside, so it becomes anti-microbial.
Food security issues are likely to get worse in the coming decades due to climate change. Are there areas of research that will help with this challenge?
One area, of course, would be climate change itself: higher temperatures, water scarcity, droughts, floods, and greater higher carbon dioxide concentration in the atmosphere. These are certainly going to affect production because if it’s going to be too hot, your crop may not do as well. Your yield is going to decrease.
You also decrease the nutritional value of food. Carbon dioxide can reduce the nutritional value of the food. It can reduce proteins, zinc, iron contents, for example. We may need to boost the nutritional value of foods with genetic engineering to remedy that effect.
And finally, climate change increases the temperature. Usually, higher temperature causes more activity by microorganisms, leading to an increase in plant disease, which will cause food waste. And, of course, drought can also cause food waste.
I think there are a number of areas that can help. Some examples include better growing techniques, regenerative farming, water use efficiency, drought-resistant crops, soil improvement practice, and precision agriculture.
Artificial intelligence is a very important area. Huge area. The USDA, by the way, is putting a lot of money into A.I. and big data. And that really optimizes various efforts, including sensors and air surveillance (using drones) to map the water supply side or crop soil conditions and find potential problems.
And, of course, the better food preservation methods, as I mentioned earlier about packaging.
In December, you’ll participate in the Zero Hunger Summit, which is part of the ACS Campaign for Sustainable Future. This online conference is organized to explore the role of chemistry in sustainable agriculture and food security. What are you hoping to come from this event?
I would like to learn the latest developments in this field, and explore collaboration. What areas can we work together, and where are there gaps? This problem is huge. It really needs collaboration. This may be a good opportunity to start that effort.
I would encourage my fellow scientists: if you have time during the second week of December to register for this meeting and actually participate in this meeting. I think it would be a great opportunity for all of us to learn more about this very important subject and perhaps we can all contribute.