How Two People Reshaped Global Food Supply

While containers had lowered shipping costs, they remained less than ideal. Simply placing a refrigeration unit in a container was not working; some goods arrived in good condition, others were ruined. Saving money on shipping only to be lost to spoilage was not a great bargain.

Sea-Land, the company McLean started, needed a better box. It found an answer during the late 1970s in Barbara Pratt, a newly graduated physics major from Cornell University who spent the next several years in a laboratory investigating what was then the little-known science of refrigerated transportation—otherwise known as “the cold chain.”

Her first project: moldy cocoa beans.

According to Pratt, “What happens typically is when the sun comes up the temperature increases inside a dry container, that would create a mini oven, and that draws the moisture out of the beans…And what happens when sun goes down at the end of the day, the water then condenses out of the air because the air temperature changes. It would then become water droplets [and] drop onto the bags of cocoa beans, and when you have excess moisture you would then have mold growing.”

To investigate what was a “black box” in terms of actual conditions in containers, Pratt made use of a unique laboratory: another container.

A 40-foot container (evidently the standard of its time) was retrofitted with living quarters on one end and laboratory space, computers, and sensor cabling occupying the rest. The Mobile Research Lab, like any other container, was placed aboard a ship, the cabling connected to sensors in containers carrying perishables and the actual environment within the containers studied at sea.

Pratt’s findings for cocoa beans resulted in changed airflow patterns. In the course of her research, she and her team looked at over 100 commodities and their findings resulted in new container designs that incorporated customized ventilation, airflow, and temperatures for a range of fresh produce. In many ways, Pratt’s redesigning of McLean’s original containers, now called reefers, made today’s cold chain possible.

An estimated 70 percent of what we eat today passes through the global cold chain. American consumers may not be aware of McLean and Pratt, or of the advances we have made in cold chain logistics. But through their efforts, as well as the work and thoughts of many individuals, the global distribution of fresh food and perishable pharmaceuticals is helping feed the hungry and care for the ill in ways that were unthinkable 50 years ago.

And that is real value.

Dr. Dinerstein is a Senior Medical Fellow at the American Council on Science and Health. Reach him at [email protected].

This article is being published with the permission of the American Council on Science and Health.