I had a bowl of strawberries for breakfast this morning, which sounds unremarkable, even in the middle of February. Thanks to growers in Florida, Mexico, and South America, I can sit at my breakfast table in the middle of a California winter, munching away on strawberries.
But for every strawberry delighting my palate, another is lost, wasted somewhere on the long road from farm to table. Of the 1.3 billion tons of food that is wasted every year, fruits, vegetables, and tubers have the highest loss: a staggering 50 percent.
Fully one-third of all food produced globally for human consumption is wasted. In the U.S. the percentage of total food waste runs as high as one-half.
Something to think about while enjoying my strawberries.
Lost in transportation
Food waste comes in a variety of flavors, at all stages of the value chain. Wasted food is a loss at an economic, social, and environmental level. Food waste is a serious global challenge, but the particulars of how and why it happens varies from region to region, says Steve Brabbs, Global Technology Leader for Transport Protection at DuPont Protection Solutions, who spoke with CR Magazine. “In the developing world,” says Brabbs, “the majority of food waste happens simply because there’s nowhere to store it.” Even while people still go hungry, a lack of refrigeration or proper storage facilities prevents this food from reaching consumers. In the developed world the leading source of food waste is, ironically, as Brabbs says, “in your refrigerator at home.” How many “science experiments” lurk in your ‘fridge? Or uneaten food that looks okay but has passed its “sell by” date?
I don’t know about you, but there’s something empowering about these data. If most food waste happens in my refrigerator, there is something tangible I can do to help solve the problem.
That takes care of a big part of the problem, but what about food that’s wasted before it even gets to me? After waste at the consumer end comes food “lost in transportation.”
“A big piece of the cause of that is handling during transportation,” Brabbs says.
Some food goes bad long before it reaches its destination. Some arrives at the grocery store only to be discarded by an overwary grocer. Brabbs explains that the most difficult situation is produce that is shipped, arrives at the store in apparently good shape, but it’s not as it appears.
“It looks ok,” says Brabbs, “but during transportation it’s been exposed to conditions which aren’t favorable.” The impact isn’t immediate, but the shelf life of the produce is diminished. The usefulness of “shelf life” is not without its detractors. This added element of conditions during transport is pushing many stakeholders in the value chain to consider a concept called “degree hours,” essentially a function time and exposure to extreme temperature.
“Once you harvest a product you can expose it to so many degrees of temperature for so many hours,” Brabbs explains. Shelf life is thus determined by the degree hours of the product: lower temperature, more hours on the shelf, higher temperature, less shelf life.
Deploying a concept like degree hours in the field is easier said than done. “[The impact of degree hours] varies enormously from one product to another,” says Brabbs, but “in general considering degree hours is quite useful.” Analyzing degree hours is another tool in the stakeholder toolbox guarding against breaks in the cold chain of transport.
Never break the (cold) chain
The cold chain is a logistical concept describing an is an “uninterrupted series of refrigerated production, storage and distribution activities, along with associated equipment and logistics, which maintain a desired low-temperature range.”
Think of a pallet of strawberries sitting on a South American tarmac waiting to be loaded into the belly of a jetliner headed north. The primary link in the cold chain here is the packaging and protective covering as the fruit sits on the asphalt in the midday sun. The strength of the link depends on the type of cover used.
A palette of goods wrapped only in plastic film sitting on a tarmac in the sun can reach temperatures as high as 133°F. Consider the cold chain broken and degree hours used up. That same pallet in the same conditions covered by DuPont’s patented Tyvek Cargo Covers heats up to only 72 °F, a substantial difference that can mean more and fresher produce reaching consumers instead of withering on the asphalt.
The cold chain goes both ways. Excessive cold will damage produce as much as extreme heat. Tyvek protects against temperature excursions in either direction.
So what exactly is Tyvek and how does it work?
The complex weave of a simple idea
Tyvek is not new. In fact, in 2017, DuPont celebrated the 50-year anniversary of Tyvek. The material is used for a range of applications, from graphics, building envelope sheathing, and protective apparel, to pharmaceutical protection and, most recently, cargo covers for perishable food transport.
Tyvek is fabricated from high-density polyethylene fibers woven in a unique process that “produce very fine pores in a very complicated, chaotic structure,” Brabbs says. This process gives Tyvek its unique qualities.
Among these qualities is not just the temperature control we’ve discussed, but high strength, and “breathability.” A function of the complex weave of Tyvek® is its ability to respirate. Similar to the cold chain, perishable produce has a range of optimal humidity. Fresh fruits and vegetables maintain internal moisture, at the same time, temperature changes lead to condensation and excessive moisture. The fibrous material used in Tyvek regulates moisture content as well as temperature.
While Tyvek, in its many formulations, isn’t new, its application for reducing food waste during transport is, relatively speaking. “The technology has been around for a long time,” Brabbs says.
“What we’ve done is understand the need and application for this particular application of shipping produce,” says Brabbs. After a thorough analysis of challenges inherent in transporting perishable produce, DuPont engineers compared these requirements with a range of Tyvek materials best suited for the application.
“It’s not a static thing,” Brabbs says, “We continue to move forward, adapt, and learn.”
No silver bullet
Food waste is a symptom of a larger “wicked problem,” one of many demanding our attention. Wicked problems oblige wicked solutions. But wait. This all started with my bowl of strawberries this morning. While the cosmic battle rages between wicked problems and solutions, let’s throw a cover over our food.
This article was originally published in CR Magazine