The world wastes an appalling amount of food. Innovative food packaging can eliminate at least some food waste. It can reduce spoilage and assure consumers that the food is still good.
Packaging in general has four basic functions. It
- protects products by separating them from the external environment.
- contains products that would be difficult or impossible to carry otherwise.
- provides convenience.
- communicates with consumers with text or graphics.
When it comes to perishable foods, packaging can also slow the process of decay. It cannot prevent decay, however. What’s more, it is not always obvious when foods have spoiled. Fear of spoilage leads to food waste when we toss what we could safely eat.
Much innovative food packaging relies on plastic, which has its own problem. More truly sustainable food packaging can eventually replace plastic films with edible biofilms.
Modified atmosphere packaging
Modified atmosphere packaging has been around for a while and already plays a role in reducing food waste. It removes some gases from the presence of food and adds others.
Mostly it removes oxygen and adds some combination of carbon dioxide and nitrogen. It can add some other gases, too. Modified atmosphere food packaging inhibits the growth of mold and bacteria. It is used for both fresh foods, baked goods, and prepared foods.
Shrinkwrapping and vacuum packaging are kinds of modified atmosphere packaging. They expel oxygen to prevent it from degrading the food.
With shrinkwrapping, applying heat causes a plastic film to shrink and fit tightly to the product. The film has tiny vent holes to allow air to escape. That means shrink wrapping can’t completely seal the food from exterior elements.
Vacuum packaging sucks air away from the product. The film collapses around it. With no vent holes, the film completely seals the contents from exterior elements. It is especially good for frozen foods. Perhaps you have bought vacuum-packed fish or other product and found the packaging very difficult to open. But once you get to the food, you can be assured that it has had little opportunity to spoil.
Some vacuum packaging uses foil instead of plastic film. It protects coffee or other products not only from air but light.
A newer innovative food packaging, intelligent packaging can monitor the condition of packaged foods and communicate it. In that way, it can help combat food waste. It does not interact with food, but it can provide useful information about it.
Some kinds of intelligent packaging can monitor temperature, humidity, and gas leakage within the package. Others can sense the food’s freshness, perhaps by monitoring microbial growth. Indicators can communicate these conditions in a number of ways. For example, they can change color.
Unfortunately, intelligent packaging comes with its own environmental problems. Consumers already reject foods close to the “sell by” date on the package. They may reject anything with a slightly discolored freshness indicator. In that case, it could actually result in more unsold food. So long as stores donate it instead of throwing it out, however, unsold food doesn’t mean food waste.
For another thing, intelligent packaging is generally not recyclable and therefore generates more waste for landfills
Active packaging is a kind of innovative food packaging that goes beyond intelligent packaging. It absorbs or releases compounds.
We have all seen packets of some inedible substance in a bottle of something. It most likely removes moisture. They have been around for decades. But now, technology can embed comparable agents in the packaging itself.
Active food packaging that removes something acts as a scavenger. Various scavengers can absorb not only moisture, but oxygen (to retard microbial growth) or ethylene (to slow the ripening process of produce).
Other active food packaging works by emitting compounds. Antioxidants, for example, or the chlorine packets in the picture. Antimicrobial emitters have not yet developed to where they are ready for commercialization, but research continues.
Slippery food packaging
Another kind of innovative food packaging doesn’t do anything to the contents. It just makes it easier to get more of them out.
Consider those little packets of ketchup you get at fast-food restaurants. They amount to two kinds of environmental menace. First, of course, is all the single-use plastic.
But you must have also noticed the impossibility of getting all the ketchup out. That means that every time you throw out one of those packets, you throw out perfectly edible ketchup. That adds to the volume of food waste. And, of course, you can’t completely empty a ketchup bottle, either. We leave behind a tremendous quantity of food simply because we can’t get it out of its container.
Scientists at Virginia Tech University have found a way to wick vegetable oil to the surfaces of the plastics used for the packaging. Food doesn’t cling to this super-slippery packaging. Vegetable oil is cheap, too.
Earlier versions of super-slippery packaging have used expensive silicon or fluorine-based polymers. Being able to use something as plentiful and inexpensive as vegetable oil can at least take care of the food waste part of the problem of plastic packaging.
Biobased cling film instead of plastic
We’re rightly concerned that plastic packaging takes a lot of landfill space. Plastic film takes little space, but it is some of the most widely used packaging for food.
We get meat, for example, in Styrofoam trays wrapped in plastic film. And so we need really innovative food packaging to replace all kinds of plastic. Biobased food packaging can eventually provide it.
One possible alternative to the films is called silk fibroin. It doesn’t have anything to do with silk fabric. It’s a collagen-like protein. Scientists at Tufts University have developed a water-based suspension with it. They have dipped fruits in the suspension, and a film self-assembles on the surface. Treated fruits don’t rot as fast as untreated fruit. And the film is both biodegradable and edible.
Cellulose and chitin are the two most abundant biopolymers in nature. Scientists at the Georgia Institute of Technology have sprayed alternating layers of chitin from crab shells and cellulose from trees to make an edible alternative to PET plastic. So far, it can block many gas molecules from penetrating it. It requires more work for it to block transfer of water vapor adequately.
Wheat gluten films have proven useful for packaging oil, salt, seasonings, and vegetables. Edible films from mango peels and seeds not only block gases but act as antioxidants. And so alternatives to what would ordinarily be itself a waste product can also help reduce food waste. And if these kinds of biobased food packaging can be scaled up to commercial production, they will replace a lot of plastic film.
Science always works more slowly than we would like, but more sustainable food packaging solutions are on the way.
Intelligent packaging in the food sector: a brief overview / Patricia Müller and Markus Schmid. Foods, v. 8, January 2019 (via National Library of Medicine)
The latest innovations in sustainable food packaging: Biobased cling film / Bezalel Adainoo, Prescouter. September 2018.
New approach to super slippery packaging aims to cut down on food waste / Emily Roediger, Virginia Tech Daily. August 3, 2018
Vacuum packing 101 / US Packaging and Wrapping
Active and intelligent packaging = longer shelf life / Claire Koelsch Sand, Institute of Food Technologists. April 1, 2020