More than a third of all of the food that's produced on our planet never reaches a table. It's either spoiled in transit or thrown out by consumers in wealthier countries, who typically buy too much and toss the excess. This works out to roughly 1.3 billion tons of food, worth nearly $1 trillion at retail prices.

Aside from the social, economic, and moral implications of that waste—in a world where an estimated 805 million people go to bed hungry each night—the environmental cost of producing all that food, for nothing, is staggering. (Read more about causes and potential solutions to the problem of food waste.)

The water wastage alone would be the equivalent of the entire annual flow of the Volga—Europe's largest river—according to a UN report. The energy that goes into the production, harvesting, transporting, and packaging of that wasted food, meanwhile, generates more than 3.3 billion metric tons of carbon dioxide. If food waste were a country, it would be the world's third largest emitter of greenhouse gases, behind the U.S. and China. (Read about the author who's waging a war against global food waste.)

John Mandyck, the chief sustainability officer of United Technologies, a U.S.-based engineering and refrigerated transport firm, says that food waste can be mitigated by improving the "cold chain," which comprises refrigerated transport and storage facilities. His company hosted the first World Cold Chain Summit in London last November. This week, Mandyck is in Davos, Switzerland, for the World Economic Summit, where he's talking up the problem of food waste. He answered questions via e-mail from Davos.

Why does the issue of food waste seem to slip below the radar?

We tend to take our food for granted in the developed world. Since food is so plentiful, we aren't aware of the tremendous amount that's wasted and the impact that has on world hunger, political stability, the environment, and climate change. Yet when it comes to looking for ways to curb greenhouse gas emissions, food wastage is a relatively easy fix—the low-hanging fruit, so to speak—and it is literally rotting on our tables. It doesn't require any new technology, just more efficient use of what we already have. (Read about the effort to rethink "use by" labels on food.)

View Images Beef sits on display at a supermarket in Dallas. About a third of food waste is due to consumers buying too much and discarding the excess. Photograph by Brian Finke, National Geographic

Food could hardly be a more important industry to humanity. Every living thing on the planet depends upon it. And yet a third of what we produce never reaches the table. Why are we so inefficient?

Food wastage comes in two forms. About one-third occurs at the consumer level, where we buy too much and throw it away. Approximately two-thirds happens at the production and distribution level. For example, a lot of food rots in fields, or is lost as a result of poor transportation networks, or spoils in markets that lack proper preservation techniques. We can make a big difference by transporting and storing our food under proper temperature conditions to extend food supplies.

What can we do better? Where should industry's and governments' focus be on reducing food wastage?

Governments can enact food safety standards where they don't exist. This will jump-start the system to properly transport and store perishable foods like meat, fish, dairy, and produce. It will also ensure that more food is safe for consumption. Industry has a role to innovate and scale technologies so they are affordable in the developing economies. Industry can also serve a useful role by raising awareness of the impacts of food wastage.

What would be the dividends?

The dividends of avoiding food waste can be historic. We produce enough food to feed everyone on our planet today and the 2.5 billion more people to come in the next 35 years. We have to waste less to feed more. Farming already uses 38 percent of our ice-free land, compared to just 2 percent for cities, and uses 70 percent of our fresh water. We can't keep growing more food, and continuing to waste as much, to feed more people. The environmental dividends are no less significant: lower climate emissions from a major source and more water efficiency to combat growing water scarcity.

And at the consumer level?

We can all take small steps that will accumulate to make a meaningful difference. Let's buy just the food we need so we throw away less. Let's accept that produce can be top quality and delicious even if it has a slight imperfection in appearance. Let's bring meals home that we don't finish in restaurants. Small changes will yield big results.

View Images Refrigeration containers, like this one at Jurong Port in Singapore, are part of the "cold chain" that helps keep food from spoiling, a major source of food waste. Photograph by Carrier Transicold

What exactly is the "cold chain"?

The cold chain is the network that transports and stores perishable foods like meat, fish, dairy, and produce under proper temperature conditions to avoid spoilage. It involves technologies like marine container refrigeration, truck-trailer refrigeration, cold storage warehouses and rooms, and food retail display cases.

Are there clever new technologies that could help improve that chain?

There are effective and affordable technologies to track and monitor food in transit to ensure it's being maintained within the proper temperature parameters. It's a proactive way to prevent spoilage at the distribution level. New entry-tier technologies are also being deployed to provide affordable truck refrigeration units for emerging markets like India. On top of that, environmental technologies like the use of natural refrigerants and energy-efficient technologies are lowering the environmental footprint of the cold chain.

How does one make these cold-chain technologies affordable in the poorest countries, where often the need is greatest?

We have to think differently. We can't take today's sophisticated refrigerated truck-trailer systems available in the U.S. and Europe and expect they can be immediately adopted in emerging countries. In many cases, the roads in these countries can't accommodate large truck systems, the technical skill is not yet present to support the systems, and the economy can't yet afford the systems. So we have to scale the technology to the local needs—smaller systems, fewer features, more affordable.